My bike is unwell!

jimbob · Post by **jimbob** » Mon Jul 16, 2012 10:32 pm

My kickstart is playing up and I was wondering if anyone has ever come across this problem before. Here are the symptoms:
When I push down the kickstarter there is no resistance. In fact there is nothing! The push rods don't move, neither does the piston. I recently had the nut on the mainshaft sheer off (a bit worrying at 30 miles an hour!)So my thoughts are that the shaft is damaged in some way. But...when I use the valve lifter or turn it in gear it all works fine. I have taken the gears apart and put them back together and they seem fine as does the kickstart mechanism. Has anyone come across this before or does anyone have any suggestions before I strip the engine? Am I missing something obvious?

cbranni · Post by **cbranni** » Mon Jul 16, 2012 11:10 pm

If it engine turns when in gear then the kickstart should turn the engine, but if theres no resistance then the kickstart mechanism isnt working, so investigation required.
Colin

jimbob · Post by **jimbob** » Mon Jul 16, 2012 11:14 pm

Thank you Colin
Any ideas on why lifting the valve stops the problem?
Or is it 'just one of those things'?
jim

Duncan · Post by **Duncan** » Mon Jul 16, 2012 11:57 pm

Clutch slip?

cbranni · Post by **cbranni** » Tue Jul 17, 2012 12:03 am

Common sense would say no, but nothing is straight forward.............kickstart will work when there is little resistance to overcome, to prove this remove the plug, if kickstart works ok, try it with plug in, if it doesn't work then there is a problem with the kickstart mech, sounds like an endfloat problem, shim or spacer missing,or in the wrong place, you haven't got the kickstart lever too tight against the casing?
This is a new one on me, if it works when you operate the valve lifter why doesn't it work when its on the exhaust stroke or the inlet stroke, and when it doesn't work are there any noises like clicking.

Duncan maybe right.........Edited by - cbranni on 16 Jul 2012 11:04:53 PM

Rob Harknett · Post by **Rob Harknett** » Tue Jul 17, 2012 12:20 am

Hang on, when you use the valve lifter the engine will kick over. Check the clutch is not slipping. I also had bikes been standing do that, clutch staying open, one had a thrust rod almost siezed hold the clutch open, cleaned and oil up then OK. Try simple no cost checks before fearing the worst.
Take the casing off and see if the clutch moves round but not move the chain, use valve lifter to see if it does move the chain and turn, you can then eliminate clutch slip & look elsewhere.Edited by - Rob Harknett on 16 Jul 2012 11:24:24 PM

Ozmadman · Post by **Ozmadman** » Tue Jul 17, 2012 1:00 am

quote:
I recently had the nut on the mainshaft sheer off (a bit worrying at 30 miles an hour!)So my thoughts are that the shaft is damaged in some way.

Has the bike been ok since the problem with the main shaft nut or has this only happened since then? Which nut sheared off the small one behind the clutch operating lever housing or the large drive gear one? It could be a damaged clutch operating rod as this goes through the centre of the main shaft, a shimming issue meaning something is not meshing correctly in neutral(there is/should be a thickish shim on the kickstart shaft) or as has been suggested already, clutch slip(for whatever reason) with compression causing enough resistance to stop the engine turning.

Paul

jimbob · Post by **jimbob** » Tue Jul 17, 2012 9:41 am

The nut which sheared off was the small one behind the clutch operating lever. The clutch rod is fine. But I will have some tinkering time tonight so I will check the clutch.

jimbob · Post by **jimbob** » Mon Jul 23, 2012 10:40 pm

Thanks everyone. It was clutch slip!