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Discussion Starter #1
A while back I posted about the dreaded 4th gear issues I was having. I broke the cases apart and installed a better, less worn used Tranny, brand new Shift drum and shift forks.

I didn't change the shift rod nor did I check it, this was an oversight and possibly a mistake. When I got the bike back on the track, I very quickly realized the probably was still there and nothing I had done, fixed the false neutral into 4th problem.

I plan to drop the oil pan and remove the side cover and extract the shift rod to replace. I have aftermarket rear sets and a dynojet quickshifter rod assembly. I bought the aftermarket shift star and roller assembly first, that didn't help. So I am running out of ideas on this problem, that is killing me at the track.

Yorke
 

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A while back I posted about the dreaded 4th gear issues I was having. I broke the cases apart and installed a better, less worn used Tranny, brand new Shift drum and shift forks.

I didn't change the shift rod nor did I check it, this was an oversight and possibly a mistake. When I got the bike back on the track, I very quickly realized the probably was still there and nothing I had done, fixed the false neutral into 4th problem.

I plan to drop the oil pan and remove the side cover and extract the shift rod to replace. I have aftermarket rear sets and a dynojet quickshifter rod assembly. I bought the aftermarket shift star and roller assembly first, that didn't help. So I am running out of ideas on this problem, that is killing me at the track.

Yorke

Do you have the problem if you disconnect the shifter?
I can only agree with you that the shift shaft needs looking at.
 

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Discussion Starter #4
I have not looked at the shift shaft either, I was talking about the rod the shift forks ride on.
 

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Discussion Starter #5
Update!!

I pulled the shift fork rod and rolled it on a flat surface, and I didn't see any noticeable bend in it. I did measure it as specified and it came out to what they listed as the service limit.

I also pulled the shift rod assembly and it did have a knock on one spot. But after looking at how it operates, I don't see how that could affect just one gear. Where it had a marred spot, it doesn't even act upon the shift drum.

I decided to order all new parts and just eliminate that from the equation. I also managed to muck up the clutch drum, the tool used to hold it slipped and messed it up pretty good. I ordered another one of those too.

I guess when it's all said and done, if there is still a problem, I'll know to look no further than the tranny itself. I'll post an update when it's all installed and I get out to the track to test it out.
 

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on an old 954 i had it would slip form 4 to second but that was cause the oil i used broke down in less in 1000 highway miles due to the bike sitting for a year...
 

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Discussion Starter #9
So I replaced the shift drum, shift forks, shift rod, shift star, all the gears. And while the false neutral problem is gone, I it is very had to shift into 4th gear. It takes a lot of pressure to the point of bending the shifter.

The only thing I can think of, is I overlooked one step and didn't coat the shift drum with Molydbendum grease? I found it in the book after everything was installed. I guess I need to pull the shift drum and inspect it for nicks and what not.

Can anyone recommend a brand for coating this piece?
 

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I'm having a similar problem with my 954 i just bought. Just curious if you've solved the problem yet? What did the gears look like when you changed them?
 

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Discussion Starter #11
Well, it ran great for a couple of track days and then yesterday while setting personal bests at the track. I lost 4th gear completely, not sure what happened, thinking my quick shifter wasn't working properly.

I had planned to freshen the motor up and do some head work anyway, so I am going to pull the motor very soon. I'll see what happened, really wishing I had the drive dogs undercut now.
 

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Hey Yorke,
interesting that we have VERY similar problems...
I recently did a complete refresh/rebuild of my 954 engine top to bottom, including fixing a 3rd to 4th to 5th shifting problem (lots of false neutrals, then eventually 4th kept popping in and out).

So, first off I just replaced all the bearings in the gear box along with 3rd and 4th input/output cogs and all three shift forks - worked fine for about 600Kms on the track before the same problem showed up again. We found lots of wrecked dogs on gears, a bent right shift fork, and a damaged shift shaft on the arm at the point where it contacts the shift drum.

So then I replaced 2nd, 3rd, 4th, 5th, input/output cogs and 6th on the output shaft only, along with all the thurst and splined washers, the right shift fork, the shift shaft and shift drum - again all good for around 6-700Kms on the track before I couldn't select 4th under full power (I have a DQS fitted too), but could go up and down through the box riding around in the pits (though it was quite notchy).

This time we went in from the side and up through the sump, to find the new shift shaft was bent where it contacted the shift drum and the right shift fork stuffed - I've decided to replace the selector drum and bearing as well this time around as it's pretty much the only thing I haven't done yet that "might" have some impact on the problem - the Haynes manual suggests that for symptoms of the gear lever not returning and an inability to select a given gear that the selector drum should be replaced. Like you, I could see some light wear in the track for the right shift fork but it hardly looked like anything to worry about...

So, if we don't get it sorted this time around - who knows where to go next ? :idunno: Short of dropping the engine and simply replacing everything in the transmission again I really don't know where to go next if this final fix doesn't work.

I should have the bike back on the track within the next couple of weeks - I'll keep you posted.

Cheers, Spanky.
 

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Hey Yorke,
interesting that we have VERY similar problems...
I recently did a complete refresh/rebuild of my 954 engine top to bottom, including fixing a 3rd to 4th to 5th shifting problem (lots of false neutrals, then eventually 4th kept popping in and out).

So, first off I just replaced all the bearings in the gear box along with 3rd and 4th input/output cogs and all three shift forks - worked fine for about 600Kms on the track before the same problem showed up again. We found lots of wrecked dogs on gears, a bent right shift fork, and a damaged shift shaft on the arm at the point where it contacts the shift drum.

So then I replaced 2nd, 3rd, 4th, 5th, input/output cogs and 6th on the output shaft only, along with all the thurst and splined washers, the right shift fork, the shift shaft and shift drum - again all good for around 6-700Kms on the track before I couldn't select 4th under full power (I have a DQS fitted too), but could go up and down through the box riding around in the pits (though it was quite notchy).

This time we went in from the side and up through the sump, to find the new shift shaft was bent where it contacted the shift drum and the right shift fork stuffed - I've decided to replace the selector drum and bearing as well this time around as it's pretty much the only thing I haven't done yet that "might" have some impact on the problem - the Haynes manual suggests that for symptoms of the gear lever not returning and an inability to select a given gear that the selector drum should be replaced. Like you, I could see some light wear in the track for the right shift fork but it hardly looked like anything to worry about...

So, if we don't get it sorted this time around - who knows where to go next ? :idunno: Short of dropping the engine and simply replacing everything in the transmission again I really don't know where to go next if this final fix doesn't work.

I should have the bike back on the track within the next couple of weeks - I'll keep you posted.

Cheers, Spanky.
I got my transmission "racecut" whit my rebuild and made the shift shaft from zx-14 billet shaft. It just need to be shortened to right lenght. I allso have Factory Pros evo shift kit and Gilles support for the spindle. Just haven't had the time to finish the bike and allso here is winter so won't be abble to test it until spring. And the it's a street bike so it won't be on so hard use but i hope it should be a lot better. I had allso gears slipping to neutral.
 

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I had allso gears slipping to neutral.

So did I when I first got the 929, but I very quickly worked out that the Honda has a longer throw on the lever than I was used to with my GSXR's. I shortened the throw and the "problem" disappeared.
 

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So did I when I first got the 929, but I very quickly worked out that the Honda has a longer throw on the lever than I was used to with my GSXR's. I shortened the throw and the "problem" disappeared.
I will put the pedal from vfr to the bike to get reversed shifting. First i have to put the motor in the frame :) How did you shorten the throw? Actually i ment slipping back to neutral from the gear when i apply throttle. The dogs were worn round on the transmission. The man who cut the transmission said the dogs where very straight from the factory compared to gsx-r or never sportbikes which he has cut the transmissions before. They don't come whit any racecut from factory but still the dogs are more shapened so there is more room for wear before they start slipping and and they engage easier. So it should be better now?
 

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I will put the pedal from vfr to the bike to get reversed shifting. First i have to put the motor in the frame :) How did you shorten the throw? Actually i ment slipping back to neutral from the gear when i apply throttle. The dogs were worn round on the transmission. The man who cut the transmission said the dogs where very straight from the factory compared to gsx-r or never sportbikes which he has cut the transmissions before. They don't come whit any racecut from factory but still the dogs are more shapened so there is more room for wear before they start slipping and and they engage easier. So it should be better now?

http://www.fireblades.org/forums/honda-fireblade/106084-race-transmission-for-929-a.html#post1144125
 

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Discussion Starter #18
So....I thought I would give an update on my 954 err. 980, :). I was having transmission problems last year, and at the last track day of the year, 3rd gear let go completely. I was done and dejected after having put a new set of gears in the bike.

I took the motor to a well known engine builder here in Texas, Race Engine Services. To get the tranny sorted out by a respected mechanic and get a super sport build. Where they shave the deck height to improve compression or simply optimize the motor, along with cam timing.

When he got into the motor we realized the cylinders were toast, so my options were to take a chance on a used motor or spend the money on an expensive build. I decided to take the plunge and have the motor bored and have the cylinders Nikasil coated. You can only bore the 954 out 1mm, so we went with that being the only option and went with the Wiseco 13.5-1 pistons.

Once that was done, I re-assembled the bike and went with stock gearing for the track I was going to here in Texas, Texas World Speedway, has some long straights. I have to run 98 octane in the motor which is also pretty pricey. The first day breaking the motor in at the track, I took it easy but could tell right away the bike is faster than before. I need to get it in for a dyno tune for the 98 octane as well as oxygenated fuels.

This week I installed the 06-07 CBR1000 forks with 08 calipers, the forks are shorter but are sprung properly for my weight. So when measuring the front ride height unweighted, it's only 7mm shorter, and when you take sag into consideration with the very soft stock front forks. I don't think the difference in length will make that big a difference.

Next up will be a slipper clutch, as well as getting my quick shifter working again. I will heading out to the track this Saturday to see how the new forks and brakes work, I am excited about this upgrade.
 
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