Help with clunky gearbox

91 VFR clunky gearbox

Hi Guys,
I have recently got a 91 VFR 750 to replace my 89 CBR 1000 and have to say i really like the bike EXCEPT the clunky gearbox. I have adjusted the chain as per manual after returning the front sprocket back to a 15 tooth. (The previous owner changed to a 16 tooth for more range) I then replaced the oil with Castrol semi synthetic to try and smooth out the gear changes. The worst 'clunk' is going from first to second but can be anywhere occasionally. The first change of the day is smooth and quiet when oil? is coldish. I suspect the chain is a bit too worn as there are a couple of minor tight spots but not too major so was wondering if this could be the problem? I have read about the kit you can get but looking at a simpler solution if there is one. Any ideas as to whether this is likely to be a chain issue or oil type? Thanks
NZPilot

 

Cush drive rubbers might be knackered and needing replacement .

Or might just be normal for that bike??

 

Yeah,
I don't know if it has them. I just took it by the local Honda dealer who says the chain is still ok, he said to check the front sprocket for wear. I took it apart and all looks all ok but have put the 16 tooth back on to see if it fixes the clunk but NO! might try going to a 15-50 mineral and see as a last resort. Otherwise it might be time for a VTR Thanks for your reply.

Cheers.

 

Loose cush drive rubbers are FAR more likely than any front sprocket problem, and changing sprockets is unlikely to help. Your dealer might be bullshiting.

Oil change probably won't help.....make sure yoiur clutch is fully releasing between shifts.

Improve your technique and coordination between clutch, shift and throttle, and adapt to the way the bike needs to be shifted.

 

Hi, Where are the Cush rubbers? In the rear sprocket housing?

 

Yes, download a parts diagram.

 

Thanks,
Got the manual. I don't have a spanner big enough for the large nut. I might order a set through the dealer and get them to fit them. Doesn't look like a big job from the diagram.

Thanks for your help Squirrelman.

 

A couple other ideas...
excessive play in clutch lever caused by missing or worn brass lever bushing or air in system. Sometimes big cushy grips don't allow full stroke on the lever.
idle speed too high or rpms don't drop off cleanly when dropping the throttle to shift.

 

Hi Dizzy,
I have bled the clutch and has plenty of travel with no binding or grabbing. I loosened the chain a bit more which has improved it noticably. When i hold the back brake on and let the clutch in and out a bit, you can see a little bit of movement in the rear hub and also gives a little bit of slap with power on/off at low speed. Looks more and more like the cush rubbers. I got a quote from the local dealer at $150 plus gst ex Japan. Will see how it goes for a while.
Cheers.
NZP