strange noise in chain case!

[scoothappy]

at first i thought my crank had twisted. it's like a knocking noise but doesn't have a rhythm. it is definitely coming from the chain case. not sure if its gear or chain slop.
info on motor:
brand new rebuild maybe 5 miles on the clock.
indian gp 150 mark1 gear box from SR
shimmed gears to spec
sprockets are 18 / 47 (82 Pitch)
only using a nylon chain tensioner which i've done in the past with no problems (i wonder?????)
have yet to open case to see whats up
just wondered if any one has any experiences like this?
thanks

[coaster]

Does the noise change/disapear when you pull in the clutch, that might help poiunt you in the right direction i.e. eliminate gearbox issues?

[eibargum]

check the spring behind the front sprocket if all else fails, my mates broke last week, first time ive seen that.

[Monty]

Kick-start rubbing the clutch, try pulling it out, you can get a thick washer to take up the travel and hold it out

[lamy150]

got any gear box oil in ?

[scoothappy]

definitly got oil in it. i tried engaging the kickstart while idling, that seems fine, but a loose sprocket and using clutch to isolate problems will help.
thanks

[scoothappy]

seems to be gear selector rubbing on the side of gears in neutral. when in gear with clutch pulled sounds goes away. since everything is brand new in gearbox thinking of just letting it break in. any advise?

[Knowledge]

Hmm. It sounds like the plunger on the kick start is not fully retracted when the kick-start returns to the top of its travel. The two teeth on the plunger will hit the teeth on the first gear an make a death rattle.

If you have the kick-start plunger cam fitted to the chaincase, it is easy to adjust the cam to ensure that the plunger is fully retracted. If the cam is built into the gearbox end plate, you will have to box cleverer or conside conversion to the other style.

[scoothappy]

I think it was the end plate layshaft race. it was not completely seated in the end plate. and was slightly cockeyed in the end plate. does anyone have any expeirience with this sort of thing. when i used a feeler gauge to check the gearbox shim it was slightly loose on one side and tight on the other!

[soullad]

the layshaft race just "locates" in the endplates above a shim and isn't actually fitted unlike the gear cluster bearing which is pressed home and retained with a circlip.
My advice is to take the gearbox completely apart and rebuild it. Check everything including the sit of the rear hub bearing firstly.
Also check the wear on the oil slot faces of the individual gears themselves just in case these have been worn too. You need to get the whole box sitting level, so that the sliding dog ears select each gear properly and do not protrude, esp in first gear.
Then make sure you shim it within tolerance.
Hope this helps
Ian