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Discussion Starter #1
It appears the dogs on second gear are wearing out (43k miles), as anything over 5k rpms it drops out of gear into neutral. On my quest for replacement transmissions I'm coming up empty for 954's, but have found a few 929 transmissions. From what I've read, they "appear" to be interchangeable. Are they (including shift forks and drum, etc)? And if so, is the gearing all the same?

It would be less expensive to just replace the worn gear, but I feel like having a transmission with 11-20k miles may be better than a trans with 43k with a new second gear. Am I wrong for feeling that way? I'd still have to factor in the cost of taking it to a shop to have them press on/off the gears for me.

Will most likely send it out for undercutting while its out. Not sure on the cost of that just yet though.
 

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It appears the dogs on second gear are wearing out (43k miles), as anything over 5k rpms it drops out of gear into neutral. On my quest for replacement transmissions I'm coming up empty for 954's, but have found a few 929 transmissions. From what I've read, they "appear" to be interchangeable. Are they (including shift forks and drum, etc)? And if so, is the gearing all the same?

It would be less expensive to just replace the worn gear, but I feel like having a transmission with 11-20k miles may be better than a trans with 43k with a new second gear. Am I wrong for feeling that way? I'd still have to factor in the cost of taking it to a shop to have them press on/off the gears for me.

Will most likely send it out for undercutting while its out. Not sure on the cost of that just yet though.

Gearing is the same.
The transmission wears very little in normal use. Second tends to wear more because it is used more and the gap from first to second is the widest in the box, but proper shifting won't cause any significant wear.
The transmission is interchangeable complete, not individual pieces.
Once you inspect your transmission you can determine if anything else is worn, but I would recommend just replacing the damaged components with new ones.
You don't need to press anything on.
You don't need undercutting, just learn to change gears more cleanly.
APE website lists pricing for undercutting.
 

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Discussion Starter #3 (Edited)
I didn't realize the gears weren't pressed on (although it should have been obvious considering how the trans works). That simplifies things.

I just purchased the bike ~2 months ago, so I'm unsure of what the PO's driving style was.

Thanks for the suggestions and help BR!
 

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I've posted on this previously (different thread) as had e same issue on a vfr750 I owned a while ago.. Second gear dogs worn. Check for the selector fork wear (often people try to hold it in gear by forcing the selector shaft) and also the gear where that worn dogs fit (it will almost certainly be worn also)..

I ended up needing to change 2 cogs and 1 selector shaft only a few months after purchasing the bike - seems I didn't ride it hard enough in the test drive (went from 250 single 4 stroke to a vfr750) - but after a month or two of ownership I was riding hard enough for the gear issues to come to light..

If you don't have one, buy a Haynes manual (or similar) and use a clean work bench, take your time, lots of digital photos (in sequence) and all should be good.. But check all cogs and selector shafts carefully..
 

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Discussion Starter #6
I plan on measuring tolerances and wear areas when it's apart.

I found a 929 transmission locally, but I'm not sure how many miles are on the thing (apparently they have to remove it and pull the stock code and whatnot to find out the mileage on the bike it came out of). The salvage yard only wants 250 for the whole assembly. If I replace two gears and maybe a fork or two, I'm already in the range of a replacement trans. So I'll keep that option as backup after I get in there at can take some good measurements.

I get the feeling I'll need to take a good look at the clutch and bearings when its apart. When the bike is idling in neutral it makes a distinctive thud/clunk that's coming from either the clutch or transmission. The noise goes away when the clutch lever is pulled.

Thanks gents, you've been very helpful.
 

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I plan on measuring tolerances and wear areas when it's apart.

I found a 929 transmission locally, but I'm not sure how many miles are on the thing (apparently they have to remove it and pull the stock code and whatnot to find out the mileage on the bike it came out of). The salvage yard only wants 250 for the whole assembly. If I replace two gears and maybe a fork or two, I'm already in the range of a replacement trans. So I'll keep that option as backup after I get in there at can take some good measurements.

I get the feeling I'll need to take a good look at the clutch and bearings when its apart. When the bike is idling in neutral it makes a distinctive thud/clunk that's coming from either the clutch or transmission. The noise goes away when the clutch lever is pulled.

Thanks gents, you've been very helpful.

It really doesn't matter how much mileage is on it, only the condition it's in now.
The problem with buying secondhand tranmissions in the US is no graded licencing system. Absolute newbies get on litre-class bikes and learn to change gears...badly. Not good when you have well over 100hp and a transmission designed to be as light as possible - they can destroy the transmission very quickly.
The random idling "clunk" is most likely the oil pump chain as it runs very loose, and is driven off the clutch basket.
But, it could also indicate a broken clutch plate.
 

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Discussion Starter #9
It really doesn't matter how much mileage is on it, only the condition it's in now.
The problem with buying secondhand tranmissions in the US is no graded licencing system. Absolute newbies get on litre-class bikes and learn to change gears...badly. Not good when you have well over 100hp and a transmission designed to be as light as possible - they can destroy the transmission very quickly.
The random idling "clunk" is most likely the oil pump chain as it runs very loose, and is driven off the clutch basket.
But, it could also indicate a broken clutch plate.
All good points.

I'll be sure to check the oil pump chain and clutch when it's apart.
 

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Is the clunk constant or like every 20 seconds my 929 does this and also pops out of second sometimes. It doesn't go to second then pop out though. Just sometimes won't go into second from first.
 

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Ive cracked my case twice and preformed a 2nd gear swap. One being an ebay swap and another being OEM parts. U will need to replace 2nd and 6th plus look at thr other dog bones. You will also need a air compressor and 30mm socket. Its time comsuming but well wirth it. I spent 280 on 2nd gear, 6th gear, shift fork, and shift drum. No more issues.
 

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Do not buy a 2nd hand tranny. My ebay tranny is still in the box. After learning dog bones and looking over the tranny. I only saved 3 of the 6 gears.. OEM is the way to go
 

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Discussion Starter #17
So upon inspection, the shift drum showed no significant signs of wear, almost looks new. 2 of the 3 forks were well within spec, the third technically was, but had some odd wear lines on the middle of the fork. The dogs on 2nd were definitely shot though. Lots of rounding. I've ordered a new fork and two gears. In the past I've done engine removal on bikes using front and rear stands. On the blade I have to remove the swingarm though, so how do you support the rear of the bike?
 

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In the past I've done engine removal on bikes using front and rear stands. On the blade I have to remove the swingarm though, so how do you support the rear of the bike?
Helpful article I wrote with misc. tips like swinger removal and support. Has stuff you don't find in the manual so hopefully it's a bit of help..

Specifically pic 2 for the answer to your question.

Good luck!! :thumb:

http://www.fireblades.org/forums/articles-honda-fireblade/107421-954-engine-removal-tips-misc-tips.html
 

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Thank you! :D

I didn't have the option of hanging it from the ceiling so I had to come up with something else. That turned out to be a very good and stable option; just takes 2 people to get it up and down (three would be ideal to setup the rear stand on reassembly but 2 works).
 
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