Acceleration jerk

[rroyter]

Hi all,

I've searched over forums but couldn't find anything definitive. Basically the problem I have is during acceleration in 1-3rd gear I feel a jerk somewhere in 5-7 RPM range. At first I attributed it to a clutch slip, you know when it no longer holds tight enough and it slips, so I replaced the plates with brand new ones. The clutch feels definitely grippier but the problem still remains.

Also today I noticed another weird thing: I can't shift into neutral while standing still. I can shift if I kill the engine and restart it, or if I drive a few feet. But I can't shift into a gear from neutral and then shift back from neutral as I definitely could do up until before I worked on the clutch. I installed APE friction and steel set and removed the metal washers together with the stock plates because the new ones wouldn't fit otherwise (if it helps in any way). Also while I was there I changed oil and I found a metal piece in the drain. The dealership where I bought it from, claimed they rebuilt the 3rd gear so maybe it's shaved off of that gear.

Any ideas what could jerk the bike during acceleration besides slipping clutch? I run a '04 Busa.

Thanks

 

[twotonevert]

How long has it been since you checked the chain, sprocket, wear etc? If the chain is jumping teeth it will jerk. Also, have you check the cush drive to make sure it is not excessively worn? That will also cause it feel like it is jerking. I cant answer the question about why it wont shift into neutral or back out. As long as my bike is running I dont usually have any issues, but since you have worked on the clutch I just dont know.

 

[Lil guy Big Busa]

Sound like the busa second gear curse to me

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[rroyter]

I have inspected the chain just last week, but I didn't look into the cush drive. What should I check for?

Again, the dealership said they did rebuild the transmission so I hope they didn't lie about it.

 

[twotonevert]

Well, I was trying to be simple and not think about the tranny yet, but if you said it was supposed to have been rebuilt, then check it out. But before you do that, it wouldnt hurt to rule everything else out. The cush drive gets worn out and can feel jerky. A good way to check it is to put it in gear while it is running and see how much jerk you feel when it goes into first. I dont think I am explaining this correctly. But you did say you cant change gears while standing still. It will feel sloppy. I hope that made sense.

 

[rroyter]

So after not riding for about 2 weeks I finally got her out for a spin. The symptoms have changed: in first 2 gears under mild acceleration it jerked 2-3 times in successive order with a distinctive metal clack. I suspect the chain is too loose and skips teeth. I'll adjust the slack later today and see if it fixes it.

 

[rroyter]

So it was the loose chain. The slack was about 3 inches and I couldn't measure more because it hit the swing arm. After proper adjustment my baby runs smooth again!