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[Norm]

This is on an Indian Bullet, motor running in neutral and every 5 seconds or so there is an audible clunk which I am convinced is from the gearbox area when I heard it.Apparently it is worse when riding. Owner has now stripped the box and nothing appears to be a problem.Gearbox has had sealed bearings fitted,I'm going to go and put it back together tonight, but I wondered if anybody had any thoughts on this. Also I got him to pull the timing cover to check the cams,tappets pumps and spindle but apparently they seem fine. This motor also has a Hitchcocks longstroke crank fitted that has done probably 25000ks

[papasmurf]

If is a regular noise at tick-over in neutral, what in the gearbox rotates once at the tick-over speed.
For instance at 900 revs that would be every 75 revs to get a clunk every 5 seconds.
If you time the clunk and accurately check the engine speed, does that match up with any of the gearbox ratios.

[simon]

And it stops with the bike in gear and the clutch pulled?

[Norm]

Good call Simon, I can't recall if this was checked, bit late now, I will have a good look at the gearbox tonight and put it back together, hopefully the problem will have gone away. Papa the noise is not regular just somewhere about 5/10 seconds apart. Gearbox mainshaft it travelling at a bit less that half engine revs

[Norm]

Checked everything very carefully, gears,timing side,cams,tappets pump spindle, put it back together and the noise was still there, backed the primary off and it got worse. Pretty sure I found it, for some reason occasionally the clutch sprocket appears to be hitting one of the ribs that support the stud the outer primary cover bolts to.

[Davie Hall]

Could it be the primary drive sprocket on the end of the crankshaft working loose. That happened to my electra and a quick tighten of the nut cured it

[papasmurf]

I used to have a Yamaha Radian that sounded like a bucket of nuts and bolts in a spin-dryer until the clutch was pulled in.
I won't start my CX500 Honda without wearing earplugs because from an engineered point of view it sound as if it is about to blow to bits. (But as we have had the bike for 25 years, and it has always sounded like it, I suspect there is nothing to worry about.)

[simon]

Another thought Norm. The slipper tensioner adjuster bolt can clack against the case making a noise such as you describe.

[Norm]

Davie, Bullets don't have the big nut that comes loose on the Electra and makes you think the big end has gone west. Papa clutch rubbers have gone hard and shrunk, not sure if you can get replacement ones now. Simon no movement on the adjuster, I ran it for quite a while with the cover off looking for any signs of the cause. It was only later when I noticed a tooth on the sprocket had clipped the web. I'm tipping he has over tightened the outer primary cover and distorted the inner case a bit pulling the web slightly forward allowing the sprocket to clip it occasionally.

[Norm]

I fitted this inner primary cover probably 35000ks ago after the original was smashed when the rotor exploded and took out pretty much everything on the primary side, just not sure why all of a sudden it has changed