Topic: Chain slap when cranking?

[racemx51]

Hey guys, getting my bike all back together and when I was testing spark I obviously kept cranking the motor for a little period of time each time.. And Every now and then Id hear a chain inside sound like it slipped and then caught after a second. Then it would crank normal again... Wouldnt happen often but...
Id imagine its not the cam chain because its tight, the motor was never taken apart and I never noticed it do it when I bought it any time I started it...

So my question is, what the hell is that? And if the only option is the cam chain, is there any way to time this bike without pulling it from the frame? Its a CB 750 and obviously the cam cover doesnt come off without pulling it...

[dave500]

starter clutch?

[Gordon]

starter clutch?

Probably.  You'd be hearing a lot worse than just a chain sound if the cam chain were slipping.  Like pistons hitting valves.

[Danno]

if you are really worried about it take the plug wires off the plugs or pull the plugs out
drain the oil
drop the oil pan
crawl under the bike
have someone crank it over while you look at the primary chain (might want safety glasses)
you will be able to see it slap if it is bad and possibly hit the case too
if it is real loose the chain tends to lump up at the bottom
if it does not then it is not the primary chain 

some clutches can stick if they sit too long and sometimes break loose while cranking

[KingCustomCycles.com]

whir-clank-bang-crank- or more whirring?  starter clutch as stated above.  You could run some seafoam in the oil to try to clean it or disassemble and clean it up.  The advantage of disassembly is you can spot a deformed roller, spring, or housing and fix it right with some used, but good parts.