Skipping gears? The truth please... [Archive] - S2000 Club of America Forums

JonBoy

10-08-2007, 08:11 PM

But how does sorting through gears without using them doing anything other than wearing down the synchros?

I've heard conflicting info on this as well for years

I routinely drop from 6th to 3rd when I want to nail it on the freeway (with rev matching)... I used to go through the intermediate gears but ended up deciding it was a waste of time and put me at a greater risk for missing a gear (particularly dangerous for the accidental engine-killing 5-2 downshift)

The synchros aren't being heavily used if you don't engage the clutch, really. You're not giving any input so the tranny is basically freewheeling along with the rest of the drivetrain behind it.

The synchros are there to help reduce the shock of having a mismatched input (revs too high or too low), causing heavy loading on the tranmission gears themselves. Rowing the gearbox with the clutch disengaged should have minimal, if not negligible, effect on the synchros.

I don't see how going into and out of a gear (6-5-4, for instance, but only engaging the clutch in 4th gear) puts you at greater risk for a misshift. It keeps you moving the shift lever in the prescribed pattern, hopefully REDUCING the chance of a misshift. People most often misshift (from what I've read) when they do NOT follow the shift pattern and just skip to another gear directly...

Jrm_41

10-08-2007, 08:43 PM

If the only problem for skipping gears is misshifts, it sounds like the driver is at fault and skipping gears does nothing to damage or help the tranny. I still do a 2-5 shift in my hatch and I've never had hany problems for the 60K+ miles of daily driving and track driving. The S doesn't have the power to move in 5th like the hatch does, but I'll do a 1-2-4-6 shift all the time in the S when driving it.

hecash

10-09-2007, 12:11 AM

I also skip gears a lot. If I'm in 6 gear and want a 3 or 4 destination gear, I just push the lever out of 6 without grabbing it, let the lever settle into the 3/4 gate naturally and either push or pull to make the 3 or 4 engagement. I've been skipping gears for 40+ years without any recognizable issues.

repiv

10-09-2007, 12:37 AM

"Woodwork" (Kent), who is one of the head techs for the S2000 and NSX for Honda USA in Torrence, CA, has preached about skipping gears. He has seen the damage that improper "skip shifting" can do. I think Desmo pretty much sums it up when it comes to this. If done properly and the loads on the drivetrain upstream and downstream of the critical parts of the transmission are equalized (think matching revs), then no harm is done. Unfortunately, many manual drivers don't have an understanding of this principle and do it wrong and this is primarily why skip shifting is discouraged. Skip shifting that results in a grind or a "hard" engagement can wear off the little points on the syncros. This will then result in more grinding and more difficulty engaging the gear even when done normally.
Here, you see a perfectly good 5th gear syncro:
http://inlinethumb49.webshots.com/21360/2375806480025981935S600x600Q85.jpg (http://good-times.webshots.com/photo/2375806480025981935aDGfgr)

Here, you see the 5-6 sleeve, with those little points ground off:
http://inlinethumb10.webshots.com/25417/2456934940025981935S600x600Q85.jpg (http://good-times.webshots.com/photo/2456934940025981935suMzDq)

Here, you see the 6th side damaged:
http://inlinethumb37.webshots.com/2404/2726203950025981935S600x600Q85.jpg (http://good-times.webshots.com/photo/2726203950025981935PkEVRM)

Coop

10-09-2007, 12:40 AM

thanks

hecash

10-09-2007, 02:23 AM

If done properly and the loads on the drivetrain upstream and downstream of the critical parts of the transmission are equalized (think matching revs), then no harm is done. Unfortunately, many manual drivers don't have an understanding of this principle and do it wrong and this is primarily why skip shifting is discouraged.

Good point. I did not even consider that someone would shift without rev-matching.:(

My_yella_s2k

10-09-2007, 02:25 AM

honda says its a BIGGG!!!!! no-no ...

4-timer

10-09-2007, 02:55 AM

to help clarify for me..... I thought the original question concerned upshifts, but many of the responses seem to deal with downshifts..... can you equal loads (revs) on an upshift?..... or I'm missing something.....

"Woodwork" (Kent), who is one of the head techs for the S2000 and NSX for Honda USA in Torrence, CA, has preached about skipping gears. He has seen the damage that improper "skip shifting" can do. I think Desmo pretty much sums it up when it comes to this. If done properly and the loads on the drivetrain upstream and downstream of the critical parts of the transmission are equalized (think matching revs), then no harm is done. Unfortunately, many manual drivers don't have an understanding of this principle and do it wrong and this is primarily why skip shifting is discouraged. Skip shifting that results in a grind or a "hard" engagement can wear off the little points on the syncros. This will then result in more grinding and more difficulty engaging the gear even when done normally.
Here, you see a perfectly good 5th gear syncro:
http://thumb15.webshots.net/t/60/460/8/6/48/2375806480025981935aDGfgr_th.jpg (http://good-times.webshots.com/photo/2375806480025981935aDGfgr)

Here, you see the 5-6 sleeve, with those little points ground off:
http://thumb15.webshots.net/t/60/460/9/34/94/2456934940025981935suMzDq_th.jpg (http://good-times.webshots.com/photo/2456934940025981935suMzDq)

Here, you see the 6th side damaged:
http://thumb15.webshots.net/t/50/550/2/3/95/2726203950025981935PkEVRM_th.jpg (http://good-times.webshots.com/photo/2726203950025981935PkEVRM)

griffon

10-09-2007, 03:41 AM

Why skip gears??

bracky

10-09-2007, 03:44 AM

Why skip gears??

If you are putting along in 4th gear and all of a sudden need maximum acceleration wouldn't you go straight for 2nd and not 3rd? Just one example. ;)

equinoxiq

10-09-2007, 03:51 AM

to help clarify for me..... I thought the original question concerned upshifts, but many of the responses seem to deal with downshifts..... can you equal loads (revs) on an upshift?..... or I'm missing something.....

on an upshift you just need to make sure that the revs don't drop any lower than whatever the revs should be in the next gear. so if your shift is too slow than the revs will drop too low, too fast and the revs won't have had enough time to decrease. skipping a gear would require a relatively long wait for allowing the revs to decrease (comparatively from going from one gear to the immediate next gear)

equinoxiq

10-09-2007, 03:53 AM

If you are putting along in 4th gear and all of a sudden need maximum acceleration wouldn't you go straight for 2nd and not 3rd? Just one example. ;)

or if you just VTEC'd it on to the highway from an entrance ramp and you're going seventy mph in third gear then it would be silly to have to shift through fourth fifth and finally sixth all while staying at the same velocity.

Geo02s2k

10-09-2007, 04:17 AM

Thank you for asking this question. I was also interested in the answer to this and am enjoying all of the responses.

Dave, I'm a little confused about the rings in your photos. If you don't force the gear lever into position, but wait until it slips easily into gear, will you still get this kind of wear? It would seem like you'd have to be either forcing the lever into gear or really missing the rev match to cause wear like that. Can you go into more detail about that?

Geo02s2k

10-09-2007, 04:19 AM

on an upshift you just need to make sure that the revs don't drop any lower than whatever the revs should be in the next gear. so if your shift is too slow than the revs will drop too low, too fast and the revs won't have had enough time to decrease. skipping a gear would require a relatively long wait for allowing the revs to decrease (comparatively from going from one gear to the immediate next gear)

This is basically what I thought. Don't rush it when you go from 4-6 and you should be o.k. Is this wrong?

griffon

10-09-2007, 04:45 AM

If you are putting along in 4th gear and all of a sudden need maximum acceleration wouldn't you go straight for 2nd and not 3rd? Just one example. ;)

I would shift into 3rd and then into 2nd before letting out the clutch.

dlq04

10-09-2007, 06:27 AM

This subject was greatly discussed in the past, so I took lots of notes - since like all of you I've skip gears for half a century without any problems. Here's my notes; make of them what you will:

Short answer: Reportedly skipping gears when upshifting can create a problem because the input shaft does not slow down quickly enough on its own, under the given circumstances, and the synchros are not up to the task of handling the speed and become mushroomed.

Long answer: A Honda engineer indicates the problem with skipping gears is the same as shifting from first to second very fast and making it grind. There are Double cone synchros in 1, 3, 4 and a single cone synchros in 5, 6, R plus a triple cone in 2nd. If you shift quickly from first to second and you don't give the 2nd gear synchro time to slow down and the 19 pound main shaft to match the next engine speed, then you will grind the sleeve as it contacts 2nd gear. All you need is constant pressure and ½ second on 2nd gear. If you put too much force you don't give the synchro time to slow down the main shaft before the sleeve hits the gear. The same is true for skipping gears. Honda does not recommend it but if you are going to do it any way you just have to give a little more time for the synchro to do its job. Double clutching on an up shift is good, if it is done correctly it will slow down the main shaft. It probably takes as long to double clutch as it does to just wait for a half second and let the synchro do its job. Beware if you like to skip 5th Gear: Pointy is good, Mushroomed is bad when it comes to the syncros. The usual customer complaint is that the transmission won't go into 5th gear. In the 5-6 shift sleeve, when it slides one way, the transmission is in 5th gear. When it slides the other way it is in 6th gear. The cause is driving the car high RPM in 1st, shift into 2nd, then high rpm into 3rd. At this time the engine is screaming it's song and the driver usually feels the need to bring the engine RPM down so he (she) shifts into 6th gear and drops the RPM 3 or 4,000. The problem is that 6th gear synchro isn't made to work that hard. (What is 5 to 6 RPM change? About 800 RPM? When that happens the sleeve slides past the synchro that is over worked and grinds into 6th gear. This will mushroom the "Dogs" on the 6th gear and on the sleeve. When the clearance between the sleeve and the hub that it rides on is small enough then the sleeve won't slip backwards into 5th. More comments on why not to skip gears: This tranny is designed differently than most trannies. Two things were done in the design to "ensure an exhilarating and quick shifting performance that meets the drivers spirited operation". (1) Normal manual transmissions have a gear reduction prior to transmitting the power to the gear selection, thus reducing the rotational speed of the gears and shafts and synchros. The S2000 transmission has the gear reduction after the gear selection. Thus the gears and shafts and synchros have a higher rotational speed. So skipping gears will be harder on the synchros of this transmission than most. (2) The S2000 transmission was designed to keep the number of number of synchro cones to a minimum. "It is impossible to ensure gear-shift exhilaration only by increasing the synchronizer capacity through the use of a multi-cone, because the shift knob load is not reduced to a satisfactory level". The engineering of this transmission put a higher emphasis on exhilarating feel and quick performance rather than making it bulletproof (and I'm glad they did). Quotes are from SAE (Society of Automotive Engineers) Technical Notes "Development of a new six-speed manual transmission", by K. Kitajima, Engineering Development Department 4, Honda R&D.

photodavo

10-09-2007, 06:46 AM

hayabusa1285

10-09-2007, 07:21 AM

kinda off topic but i have also was wondered. i had no teacher when it came to driving everything i know i learned on my own. now i have gotten in mean fights about rev matching do u do it before u put it into to gear or after it into gear

equinoxiq

10-09-2007, 01:15 PM

Thanks for the in-depth explanation, Dave.

hayabusa:
I'm in the same boat as you, i'm learning everyday and have no one else but myself and short articles in car magazines to help me out. But I'm confused by what you're saying.
What about your clutch usage? When you talk about putting it "into gear" is the clutch pedal pressed or released? If the clutch pedal is still pressed and by putting it into gear you mean the action of shifting from neutral to another gear then i don't know if it makes a difference. I can't say for sure nor can i say for sure when i actually do it, myself. For me, the entire shift just kinda melds into one whole transition.

However, if by putting it into gear you mean releasing the clutch pedal then it's already too late to match the rpm after putting it in gear. The clutch will have to match the revs for you which can cause excessive wear while the pedal is being released.

Someone feel free to correct me if this is wrong

CMan

10-09-2007, 03:24 PM

Just to throw some more information out there, I found this website to be helpful when it comes to learning how to drive a stick:

http://www.standardshift.com/

001s2k

10-09-2007, 03:32 PM

it only matters if your trying to keep your rpm's up to stay in v-tech otherwise, I do it at time's by accident and on purpose. Having raced cars before it did not hurting the engine, trans, or clutch if you know what you are doing.

dlq04

10-09-2007, 03:55 PM

I don't claim to be an expert but here's my approach. Personally, under normal driving, I take a fraction of a second to "blip" the throttle between gears while the clutch is down. I generally do this for both up-shifting and down-shifting. I presume that's what is popularly called "rev matching". To me it's a good habit as it keeps the car balanced and smooth. By doing it all the time it become second nature. It avoids upsetting the car when down-shifting and according to our Honda expert avoids having to rebuild the transmission at some point. At the track rev matching is key to down-shifting smoothly for engine braking and corner set-up but not so, at least IMO, up-shifting when you're usually in high rpms and really concentrating on shifting quickly.

As for skipping gears, say 5th, I don't do it nearly as often as once did but I still do it. I think taking the fraction of a second to blip the throttle hopefully aligns the stars enough that no damage is done.

repiv

10-09-2007, 04:10 PM

to help clarify for me..... I thought the original question concerned upshifts, but many of the responses seem to deal with downshifts..... can you equal loads (revs) on an upshift?..... or I'm missing something.....

Skip shifting on an UPshift, without due regard to matching revs is dangerous as it can do damage as per my last post with the pictures. Skip shifting on a DOWNshift is dangerous for an ADDITIONAL reason - that being it is very easy to disregard where the engine speeds will be once the shift is completed (mechanical over-rev**). Equaling loads and revs means that you ensure that the speed of the input side of the tranny is more or less the same as the output side of the tranny. When you do a fast UPshift without letting the revs drop down to a suitable rpm, you are "ramming" the input side into the output side. The gears and shafts on each respective side are turning at vastly different speeds. This works the syncros tremendously, possibly to the point of "beating the syncros" and initiating a grind. You don't only "match revs" on a DOWNshift. It is just as critically important to match revs on an UPshift.
(Please note that I use the term "match revs", instead of "rev match". There is a big difference. One primarily means to blip the throttle to increase revs at the time of shifting. The other can mean both revving UP and allowing the engine to rev DOWN.)

** A mechanical over-rev is created when the drive wheels powers the engine. We normally think of the engine as powering the drive wheels. The rev limiter does NOT help when the drive wheels sends power back up the drivetrain.

equinoxiq

10-09-2007, 04:12 PM

As for skipping gears, say 5th, I don't do it nearly as often as once did but I still do it. I think taking the fraction of a second to blip the throttle hopefully aligns the stars enough that no damage is done.

but i thought the issue you were pointing out in your previous post was how the rpm would still be too high when upshifting so blipping the throttle would only increase the rpms creating even more of a difference between what rpm the engine is actually running and where it needs to be to match the next selected gear

repiv

10-09-2007, 04:44 PM

If you are putting along in 4th gear and all of a sudden need maximum acceleration wouldn't you go straight for 2nd and not 3rd? Just one example. ;)
Firstly, with the exception of maybe highway cruising, one shouldn't be "putting" along to the point of nearly lugging the engine. Driving at a normal rpm range should allow you to downshift ONE gear and have sufficient motivation for an emergency acceleration maneuver.

skipping a gear would require a relatively long wait for allowing the revs to decrease (comparatively from going from one gear to the immediate next gear)
You are correct, "relatively" speaking. ;) I guesstimate a "normal" upshift to take about a second. When skip shifting, one should wait till the revs drop down to near idle. This might take only an additional second, so not so long. Do an experiment ..... Next time you're driving along at an rpm where you might want to do an UP skipshift. Now, just push in the clutch, let off the gas and see how long it takes for the revs to come down. That's about how long it should take to do a "proper" UP skipshift. This is "matching revs" DOWN.

or if you just VTEC'd it on to the highway from an entrance ramp and you're going seventy mph in third gear then it would be silly to have to shift through fourth fifth and finally sixth all while staying at the same velocity.
Yes, this would be silly ....................... sort of. I do this quite often. The law says you can't speed, but it doesn't really say anything about how quickly you get up to speed so long as it's safe and you're not "laying rubber" the whole time. I don't skip shift in this scenario. I would rev it up to get up to speed, shift into the next gear but stay the same speed till the gear is fully engaged and the driveline is all connected up, then shift again and do the same, then again till I reach a gear and an rpm that is commensurate with the road speed I'm going. It be "silly" but it's just as simple to do and there's less wear and tear on the tranny. But to each, his own.

If you don't force the gear lever into position, but wait until it slips easily into gear, will you still get this kind of wear? It would seem like you'd have to be either forcing the lever into gear or really missing the rev match to cause wear like that. Can you go into more detail about that?
"Forcing" is a matter of personal perspective. What constitutes forcing for one person may not mean the same thing to another. Let's say you've got a grindstone wheel spinning away at top speed. You then place another grindstone (on a bearing and shaft) up against it. At what rate would you introduce the one grind onto the first grindstone so you get the minimum of sparks. That's sort of what you're doing to the syncro teeth when you introduce one tranny gear to the next. They can handle a certain amount of "grinding", but at some point, they do wear out.

about rev matching do u do it before u put it into to gear or after it into gear
You want the engine speed to be at the appropriate rpm to "match" the speed of the drive wheels. To do this you must bring the rpm to that speed just prior to engaging the next gear, whether it be up or down. You need to raise the rpm for the next gear DOWN and lower the rpm for the next gear UP. You rev for one and you just let engine mass slow it down for the other.

However, if by putting it into gear you mean releasing the clutch pedal then it's already too late to match the rpm after putting it in gear. The clutch will have to match the revs for you which can cause excessive wear while the pedal is being released.

Correct! You want the revs matched BEFORE the tranny is put into the next gear. Matching revs happens while the clutch is DISengaged, UNLESS you are "double clutching". About the only time you really need to double clutch is when going into 1st gear at a relatively high rate of road speed.

but i thought the issue you were pointing out in your previous post was how the rpm would still be too high when upshifting so blipping the throttle would only increase the rpms creating even more of a difference between what rpm the engine is actually running and where it needs to be to match the next selected gear
Correct, again! No need to blip throttle to match revs on an UPshift. The revs need to come DOWN, not up. Blipping it would only prolong the agony. The revs would then climb before they come down. Just let them come down from the get go.

dlq04

10-09-2007, 04:48 PM

but i thought the issue you were pointing out in your previous post was how the rpm would still be too high when upshifting so blipping the throttle would only increase the rpms creating even more of a difference between what rpm the engine is actually running and where it needs to be to match the next selected gear

To me, it's a hard subject to discuss in writing....... much easier to with show and tell. I blip out of habit but probably pause afterwards. Does that help? :rolleye2: To be honest, I don't understand repiv's last explanation either - confusing isn't it?

I was also under the impression that the majority of the issues were resolved with changes from 2004 on:

• A tighter secondary gear reduction ratio (1.206 vs 1.16) to provide a bit more snap off the line and to better match the characteristics of the new motor. This is also called the intermediate ratio and is the gear after the transmission and before the driveshaft. It goes like this: Crankshaft --> clutch --> transmission (gears 1-6 + R) --> intermediate ratio gear --> driveshaft --> rear diff --> axles

• 4% shorter ratios for 1st through 4th gears while the 5th ratio is effectively 1% shorter and 6th is effectively 2% longer, for a slightly more relaxed cruise speed. 5th gear ratio changed from 0.971 to 0.942. 6th gear ratio changed from 0.811 to 0.763.

• Carbon fiber synchromesh replace the solid brass ones for all gears except reverse. The new design features a brass ring with a carbon fiber element bonded on the inner surface, resulting in simplified mechanical components, increased synchronizer capacity, improved abrasion resistance, and reduced weight. The weight reduction and increased capacity translates to a smoother and quicker shifting feel. Further enhancing shift feel quality is a reduction in the load acting on the disc spring. Per Honda, this tweak results in reduced shift knob operational load and reduced harshness.

• transmission case rigidity improved

repiv

10-09-2007, 05:09 PM

To me, it's a hard subject to discuss in writing....... much easier to with show and tell. I blip out of habit but probably pause afterwards. Does that help? :rolleye2: To be honest, I don't understand repiv's last explanation either - confusing isn't it?

I was also under the impression that the majority of the issues were resolved with changes from 2004 on:

• A tighter secondary gear reduction ratio (1.206 vs 1.16) to provide a bit more snap off the line and to better match the characteristics of the new motor. This is also called the intermediate ratio and is the gear after the transmission and before the driveshaft. It goes like this: Crankshaft --> clutch --> transmission (gears 1-6 + R) --> intermediate ratio gear --> driveshaft --> rear diff --> axles

• 4% shorter ratios for 1st through 4th gears while the 5th ratio is effectively 1% shorter and 6th is effectively 2% longer, for a slightly more relaxed cruise speed. 5th gear ratio changed from 0.971 to 0.942. 6th gear ratio changed from 0.811 to 0.763.

• Carbon fiber synchromesh replace the solid brass ones for all gears except reverse. The new design features a brass ring with a carbon fiber element bonded on the inner surface, resulting in simplified mechanical components, increased synchronizer capacity, improved abrasion resistance, and reduced weight. The weight reduction and increased capacity translates to a smoother and quicker shifting feel. Further enhancing shift feel quality is a reduction in the load acting on the disc spring. Per Honda, this tweak results in reduced shift knob operational load and reduced harshness.

• transmission case rigidity improved

If you're referring to this:
No need to blip throttle to match revs on an UPshift. The revs need to come DOWN, not up. Blipping it would only prolong the agony. The revs would then climb before they come down. Just let them come down from the get go.
Let me rephrase it to help clarify. When UPshifting, the revs need to come down before engaging the gear. This should be reasonable since after you upshift, the revs are lower. My point, being that, if the rpm needs to come down, there is no need to "blip" the throttle. Blipping the throttle momentarily raises rpm. It just makes it a longer process to raise rpm first before it can come down. Since it's down that you want, why go up first?

When they say that the issues are "resolved", one has to define what those issues are. The issues that are resolved constitute those to do with lack luster "get up and go" in the lower gears. This was resolved by changing the overall gear ratios of the first 4 gears by changing the ratio of the secondary reduction gear. Then 5th and 6th gear was changed so that hiway cruising rpm was not compromised (elevated). What this did was, in fact, expanded that gap between the lower gears and the top 2 gears, making skip UPshifting even more arduous for the syncros. If you compare the final gear ratio on all gear with this speed calculator, you will see the numbers clearly:
http://www.turnzero.com/technical_resources.php?resource=gear_calculator

However, since we're discussing what's good and what's bad on the tranny when skip shifting, that is the "issue" being dealt with here. As per:
improved abrasion resistance
Note the term "improved" being used. This, by no means, implies that abrasion is eliminated. Certainly, with the newer parts in the later transmissions, skip shifting would do "less" damage when done improperly, but this doesn't mean that no damage is being done.

Going back to my grindstone analogy, let's put an oversized soft rubber disc next to the actual stone wheels, so that the rubber discs take the initial friction and spin up the second stone wheel just before the 2 stones touch. Instead of wearing out the stones, you wear out the rubbers, right? Well, the rubbers are your syncros by analogy. So, you put on better rubbers. They don't wear as quickly, but they still wear. And if you ram them together hard enough, even the "better" rubbers won't last forever.

equinoxiq

10-09-2007, 05:15 PM

i'm glad this thread was started. as i said before while i feel i know a good amount about driving and shifting there's always more to learn. i'll probably just stay away from skip shifting because even with practice it's always harder to gauge the matching of revs. It's not something i did often anyway but i'll just drop it completely.

raymo19

10-09-2007, 05:41 PM

Hmmm...So it would seem the consensus is once again "It all depends on how you go about it".

I've rarely skip shifted either up or down since I've owned the car but it seems to me I've probably done more syncro "damage" on those occasions when I've completey blown a shift.:D

dlq04

10-09-2007, 10:51 PM

If you're referring to this:

Let me rephrase it to help clarify. When UPshifting, the revs need to come down before engaging the gear. This should be reasonable since after you upshift, the revs are lower. My point, being that, if the rpm needs to come down, there is no need to "blip" the throttle.

That's much clearer. Although I'm still not sold that is true (that the revs need to come down) if you are not skipping gears (up or down). I also believe there is a great deal of variance between the AP1 tranny's. Can't speak for the others. Mine for example, has had a 3rd gear notchy feel to it from day one at moderate shifting speeds. Slower is better and faster is better yet but moderate can be frustrating.

Actually it was your use of 'matching revs' vs 'rev matching' that confused me. When I blip the throttle I don't do it much - essentially I just maintain the revs I had. So we are probably saying the same thing (I think).

As for issues resolved - I don't hear the topic of gearbox complaints coming up any more......so I assumed Honda did something right.

repiv

10-09-2007, 11:39 PM

As for issues resolved - I don't hear the topic of gearbox complaints coming up any more......so I assumed Honda did something right.
I'm not sure exactly what the complaints were about AP1 trans, but I can say that I've observed quite a few complaints about AP2 transmissions popping out of 1st and 2nd. They may have gotten some things right only to make a couple other things bad.

raymo19

10-10-2007, 12:03 AM

I'm not sure exactly what the complaints were about AP1 trans, but I can say that I've observed quite a few complaints about AP2 transmissions popping out of 1st and 2nd. They may have gotten some things right only to make a couple other things bad.

Dave -

Do you have your AP2 tranny in now? If so are you experiencing any problems?

Just looking at options down the road.;)

repiv

10-10-2007, 12:33 AM

Dave -

Do you have your AP2 tranny in now? If so are you experiencing any problems?

Just looking at options down the road.;)

Yes, I've had the AP2 tranny (brand new) on since last spring (and the ACT HD clutch PP). I believe it's an early edition AP2. Except for the 2nd gear pop out, the ratios in the tranny, along with my 4.44 gears and supercharger, the car is everything it should have been for me from the beginning. An AP2 tranny is just perfect for an AP1, even without other mods.
This 2nd gear pop out is only during full engine braking as the revs transition from about 5000 rpm to about 2500 rpm. This is the same rpm range on decel that created the infamous early AP1 clutch buzz. The vibration upon deceleration in the tranny is still there, but on some transmissions, it pushes second gear out of engagement. I think the later AP2 trannies have this resolved by a modification in the shift linkage retention when in gear.
This pop out is not a problem for me as I have developed the instinctive technique of keeping my hand on the stick (only light pressure needed) during the transition through those rpms when in second gear decel. However, if I were to auto-X the car, this would be an extreme detriment and would need fixing, as I would require both hands on the steering wheel during most of the the vehicle's operation. Since I don't track the car in this manner, this is not an intolerable situation. Mind you, once I change tranny fluid again next spring, this issue may no longer exist. It doesn't bother me enough to do it now.
When you buy yours, try to check the build date on it so you know you are getting one of the later ones.

raymo19

10-10-2007, 12:56 AM

So far my AP1 tranny has been bulletproof except for driver error. In fact it seems smoother now than when I bought it (~43000 miles now, 4800 then). I'm thinking now with the 4.57s and the Comptech blower I'll just try really hard to make the original go the distance.

I still think it's the smoothest shifting system it's been my privilege to own (not necessarily drive).:rockon:

repiv

10-10-2007, 06:25 AM

So far my AP1 tranny has been bulletproof except for driver error. In fact it seems smoother now than when I bought it (~43000 miles now, 4800 then). I'm thinking now with the 4.57s and the Comptech blower I'll just try really hard to make the original go the distance.
If I had the 4.57 gears, I most likely would not have gone with the AP2 tranny. I just wanted that extra little "kick". With 4.44 and the AP2, my final drive in the first 4 gears is "like" about 4.6x, while in 5th and 6th, it's more like 4.40.

smac2K

10-12-2007, 04:25 AM

Thanks for the explanation Dave. I was the passenger telling Justin it was a bad thing to do but I really didn't fully understand why. I was mostly just reiterating things that I have read here from those much more knowledgeable than me. So, Justin, are you going to change your ways now? :D

I have to say, Davo that YES! I have all but stopped, OK well not completely - but I pay attention to where my revs are when I do my upshift. But for the most part I have just been going into 5th and then 6th...

Thank you everybody for your feedback!!!! :rockon:

Maybe this will be an "archived XViper Thread," and will help people in the future!!! :congrats:

Alexei

11-03-2007, 01:53 PM

Thanks everybody... some great info on this site.

Honda is pretty clear on this subject - 'Skip Shifting' is not good.

Clickie ---> Skip Shifting Is Bad For Synchros (http://www.in.honda.com/Rjanisis/pubs/SN/A060100.PDF).

Ceolmhor

11-17-2007, 11:09 PM

Let me rephrase it to help clarify. When UPshifting, the revs need to come down before engaging the gear. This should be reasonable since after you upshift, the revs are lower. My point, being that, if the rpm needs to come down, there is no need to "blip" the throttle. Blipping the throttle momentarily raises rpm. It just makes it a longer process to raise rpm first before it can come down. Since it's down that you want, why go up first?

Well, I don't "blip", as a rule, a but I'm ancient enough to explain the theory. I don't know if it's relevant to modern, more efficient automotive technology or not.

This thread has spoken of "rev matching" as if there were only one piece of matching to be done. Actually, there are two. You need to match the speed of the two gears that will next mesh, so that no clashing and damage can occur. You also need to match the engine speed to the next-correct rotation speed of the input shaft of the transmission. These two pieces of rev matching do not have to occur at the same time.

Suppose you shifted without disengaging (depressing) the clutch. Then the output shaft of the engine and the input shaft of the transmission would be locked together by the clutch, and there would be only one rev matching operation. If you disengage the clutch, however, you could for example, hold the engine speed high while allowing the input shaft of the transmission to slow down until it reached the correct speed for shifting. Clearly, this rev matching operation is independent of rev matching the engine. Then you could allow the engine to slow until it reached the correct speed for engaging (releasing) the clutch. Then you release the clutch and you have a smooth, albeit slow, shift.

Obviously, you really want to allow both the engine and the input shaft to slow down, but notice that with the clutch disengaged (depressed), they slow down at different rates as a function of their different angular inertia, viscosity of the transmission oil, and other factors. To get a smooth shift, you need to shift at the correct time relative to the gear meshing, and engage (release) the clutch at the correct time relative to engine speed.

The "blip" has potential relevance because when you disengage (depress) the clutch, you're merely removing the clamping force on the clutch disk. You're not actually eliminating the friction between the clutch disk and the flywheel. The lighter the input shaft of the transmission, the greater its tendency to continue turning at the same rate as the engine, just because the small amount of friction between the clutch disk and the flywheel-clutch assembly is sufficient to overcome the natural inertia difference between the engine and the input shaft. As a result, the input shaft does not slow down as rapidly as it would if the connection between it and the engine were actually entirely severed. What the blip does is to accelerate the engine, causing the clutch disk and the flywheel to actually part company, and allowing the input shaft of the transmission to actually slow more rapidly than it would if it were still tied to the engine speed. This allows you to move the shift lever smoothly into the new gear a fraction earlier than you otherwise would. It therefore gives the illusion of faster shifting.

But of course, you still have to wait for the engine to slow down (or be willing to put a heavy load on the clutch) before you can complete the whole shifting-and-reengaging-the-clutch operation. So I suspect that in an S2000, the earlier ability to move the shift lever into the new gear doesn't actually represent a faster shift. In the old days (and maybe today in a car with a less efficient shift linkage than the S2000), you might actually be able to perform the entire operation more quickly this way, since the act of moving the shift lever could itself occupy significant time, during which the engine was continuing to slow.

That's the way I learned it, anyway (in the 1960's, when I raced a Formula Vee and drove an MGB). Just my 2c.

Rudy

Chickwithastick

10-17-2008, 07:54 PM

I can't read this thread anymore without commenting....

It seems to me that a lot of the people posting in this thread HAVE NOT torn apart a transmission and don't actually KNOW what goes on in there.

Gear skipping is perfectly fine. Just make sure you rev match or AT LEAST double clutch.

I would shift into 3rd and then into 2nd before letting out the clutch.

^^^WHY!?!?!?! I have seen some people saying it helps not wear down your synchros!! OMFG BS!!!! This is the epitome of a wrong theory... shifting into ANY gear whether you let out the clutch or not does put wear (even if minute) on your synchros.

Honda is only trying to keep stupid people from doing stupid things. Keep skip shifting all you want!... as long as you know how to properly.

/rant

repiv

10-17-2008, 09:21 PM

It seems to me that a lot of the people posting in this thread HAVE NOT torn apart a transmission and don't actually KNOW what goes on in there.

Gear skipping is perfectly fine. Just make sure you rev match or AT LEAST double clutch.

shifting into ANY gear whether you let out the clutch or not does put wear (even if minute) on your synchros.

Honda is only trying to keep stupid people from doing stupid things. Keep skip shifting all you want!... as long as you know how to properly.

You are right about nobody tearing into a tranny who have posted here. However, trannies have been torn into and the results have been photographed (as in the first pictures I posted on page 1). Woodwork, with Honda USA, gets these parts and has described at length, the shortcomings of people "skip shifting". We must keep in mind that many, many owners of S2000s have never had any experience with a manual car and almost nobody comes with experience on close gated, short throw, 6 speed manuals. We've come from generations of people who have driven nothing but FWD cars that have been mostly automatics. Take a look at some of the threads we see to this very day about people who haven't got a clue about shifting or the way the tranny on an S2000 should feel, sound or work. You are absolutely correct about skip shifting being perfectly fine, IF it's done correctly. That's the rub. Many people don't know how to do it correctly.

You're also correct about the syncros getting worn even on normal shifts. That's what they are there for. That's just acceptable, normal wear and sometimes, people get paranoid about it and go just a bit nuts.

Yes, Honda is trying to keep stupid people from hurting their cars, but let's face it, there are a LOT of stupid people out there. Why do you suppose they added this Clutch Delay Valve on AP2s. They were watching the Stupid Meter go into the red.

We can admit that skip shifting is not an issue and we can even tell people to go and do it all they want and we can add in a caveat saying that they must do it properly, BUT, can we be sure that most people WILL do it properly or that they even know HOW to do it properly? Some people don't even understand the concept of "matching revs" nor do they have a clue as to how to "double clutch".

RacingEmotions

10-18-2008, 01:20 AM

i guess i'm different. i love going through all the gears whether neccesary or not. it was the whole reason why i even got a car with a manual transmission and gave me an even helped me to purchase my S2000 since i now have a 6-speed as opposed to my 5-speed gsr. but thats just me.

wildncrazy

10-23-2008, 04:22 PM

I found that if I use only 1-4 for any length of time, like on a track day, that 5th won't even engage. it's as if it's locked out. It will gradually come back but it will take days.

A long, long time ago there was a thread about this and even a TSB I think. All info on this has dissappeared from the public conciousness.

nuklearmaniac86

10-30-2008, 07:43 PM

Yes, I've had the AP2 tranny (brand new) on since last spring (and the ACT HD clutch PP). I believe it's an early edition AP2. Except for the 2nd gear pop out, the ratios in the tranny, along with my 4.44 gears and supercharger, the car is everything it should have been for me from the beginning. An AP2 tranny is just perfect for an AP1, even without other mods.
This 2nd gear pop out is only during full engine braking as the revs transition from about 5000 rpm to about 2500 rpm. This is the same rpm range on decel that created the infamous early AP1 clutch buzz. The vibration upon deceleration in the tranny is still there, but on some transmissions, it pushes second gear out of engagement. I think the later AP2 trannies have this resolved by a modification in the shift linkage retention when in gear.
This pop out is not a problem for me as I have developed the instinctive technique of keeping my hand on the stick (only light pressure needed) during the transition through those rpms when in second gear decel. However, if I were to auto-X the car, this would be an extreme detriment and would need fixing, as I would require both hands on the steering wheel during most of the the vehicle's operation. Since I don't track the car in this manner, this is not an intolerable situation. Mind you, once I change tranny fluid again next spring, this issue may no longer exist. It doesn't bother me enough to do it now.
When you buy yours, try to check the build date on it so you know you are getting one of the later ones.

xviper, I have a MY04 w/ 60k miles. I had the 2nd gear pop ever since I got it and i have always used the stock Honda MTF. I tweaked my fluids this time and have about 4k miles on a 50/50 mix of Amsoil MTF (5w-30) and Honda MTF and have not had the 2nd gear pop since. My shifts have also become smoother cold and hot and is not as notchy as before. When cold it takes a little more pressure to put into gear, but not that much at all, like maybe another pound. But since this is still on your first oil change, who knows if it will still happen on ur next oil change. Each transmission has a mind of their own, like a picky child.

repiv

10-30-2008, 08:30 PM

xviper, I have a MY04 w/ 60k miles. I had the 2nd gear pop ever since I got it and i have always used the stock Honda MTF. I tweaked my fluids this time and have about 4k miles on a 50/50 mix of Amsoil MTF (5w-30) and Honda MTF and have not had the 2nd gear pop since. My shifts have also become smoother cold and hot and is not as notchy as before. When cold it takes a little more pressure to put into gear, but not that much at all, like maybe another pound. But since this is still on your first oil change, who knows if it will still happen on ur next oil change. Each transmission has a mind of their own, like a picky child.
I have changed my shifting habits to the extent that I instinctively keep my hand on the shifter whenever I decelerate in 2nd, so I don't even know if it pops out anymore. I must try it the "normal" way again to check. If it still does it, I think I'll try your 50:50 mix at next spring's fluid change. I'm just wondering what's in Amsoil MTF that would stop the pop-out. :think: Being tougher to put into gear when cold is not a concern to me. Until you've tried to shift after the car has sat outside overnight at -38*C, you will think any other shifting feel is light and easy. :shifter: