I have a 'R' registration Honda CB1000, with 16k on the clock. When I come to neutral to 1st it sometimes clunks so hard that it stalls the engine. It sometimes clunks through the gears whilst travelling, and it doesn't seem to make much difference whether hot or cold. I spent a hour clean the gunk and **** off the chain, and sprockets the other day, and when I rode it after it was as smooth as a baby's bot. Then I came to it yesterday, and CLUNK, jolt and stall, after a few gear changes it improves a bit, but what is up with it? Is is CRITICAL, or does it want a tweek. The previous owner looked after her quite well, and he had for 10 years. I have owned it for 6 months, and am quite begrudged to part with her, but she is driving me nuts.HELP !!!!

You have a vacuum leak

Older 4 speed transmissions were known for their "clunk" going into 1st gear.

However, even though you didn't give a model year, I'll assume you mean something newer than those.

If it "grabs" when going from neutral to 1st (bike wants to "jump"), it usually means the clutch push rod (under the primary cover's "Derby cover) needs adjustment, followed by the clutch cable.

As far as the leak where the cable enters the transmission, there is an "o-ring" seal that might need replacing.

I think you should check your clutch adjustment. You can take a look at a generic service manual here: http://hrca.onda.com/

Over heating ... Check all of your engine's cooling systems ... fins, air flow .. This engine is air and oil cooled. Are you getting a overheat warning or does it just stop?

First you need clutch setting to be done & the second common problem is that whn ur side stand is down ur bike will stall. its a safty feature given by yamaha. Hope this solves ur question

sounds like the clutch is worn out

It sounds like your input clutch seals are rolling. Is the check engine light on. It could also be the pressure control solenoid could be causing the problem aswell

near the throttle body there is an adjusting screw(flat head) for air fuel mixture, it's on a deep cavity sometimes with a cover, adjust counterclockwise will increase the idle.

hello and welcome
this is most likely caused from a wearing clutch. when the clutch is held in there are a series of clutch plates that seperate. and allow ease of drive force from the main shaft to the counter shaft. but if the plates get worn they tend to not disengage as well. and the gears do not engage as easily and finding neutral can be hard to find or impossible to do sometimes.
to fix this the clutch plates both the fibers and steels need to be inspected for warpage. im sure you will find the fault there. thank you.

Big Twins clunk too, especially into 1st with a cold motor, even if you free the clutch off first. When I remember, I snick it into gear, pull in the clutch and roll it back and forward to free off the plates. And it still clunks. Sometimes, you will slip from neutral into 1st, almost with no effort, and no clunk and so smooth you don't believe it's engaged (but it is). Weird. I have smooth changes from 4th to 5th and back again, sometimes from 3rd to 4th, but 3rd to second and second to 1st are always a BIG clunk, even if you give it some stick to try and match the revs before changing down. I now go from second to neutral and then into 1st, which is not a lot of fun when you are negotiating a hairpin on Glenquaich at the time... A tighter primary chain seems to reduce the clunk, and there are those who say that auto primary adjusters/tensioners (does a Sporty have one of them?) reduce the clunk. Some disagree... Assume you find it's much better when it's hot..