Engine Running Loud and Popping/Stalling on Throttle

[allanrps]

I started my bike for the first time in quite a while, and the bike is very loud. The sound coming from the engine sounds like a loud clunking, not too different from the ticks the engine usually makes but quite loud. I did read that these bikes are loud when the valves are adjusted on the loose side, but this seems to my inexperienced ears to be too loud to just be valve rattle. The noise is primarily coming from the right cylinder. Also, when I apply throttle, the bike will quickly start popping and falling off. I suspect that my ignition timing is off, but I am not sure if that would cause the loud noise. I just wanted to get your opinions on what might be the issue. Thanks!

Here's a video of the sound:

 

[xschris]

Sounds like a really bad valve adjustment.

 

[allanrps]

The thing is I've set the valves like a dozen times now. Check, double check, reset, check once more. Is there something about this I'm missing, because it seems pretty straight forward. TDC on the compression stroke, make sure they are loose, set gap, secure, check gap using multiple feeler gauges. Would really loose valves cause the backfiring and falling off under throttle?

Off to go check again...

 

[Sesty]

get a buddy to hold the crankshaft steady! if it shifts back at all it mess up the adjustment.

 

[xschris]

What sesty said and do them from left to right. Make sure the marks line up perfect.

 

[allanrps]

Nothing I haven't seen before, but I'll go at it again. I've been lodging the wrench holding the crankshaft into the footpeg/ground. I do have a non-stock flywheel with a measured TDC marking that is not 100% accurate, but from inspecting the camshaft I don't think it needs to be perfect TDC. I did check the valves for play before setting them anyway. I'd be thrilled if all it needs is a valve adjustment.

 

[xschris]

I think without the proper LT and RT marks for the fly wheel your not going to get a good adjustment.

 

[allanrps]

I looked like there was like a 120 degree section on the cam shaft for each cylinder where both cams are at their 'zero', where it is round and doesn't lift the valve. Is there something I'm missing? Thanks for the help.

 

[xschris]

Never used the cam for finding crank position before. Remember you need to take into account chain slack. The mark needs to be dead on. A sort of around it will through it off

 

[Wolfe_11B]

Well if I were to do a PMA swap (which I wouldn't), I would mark TDC on the new flywheel using a dial indicator. After that, use a degree wheel to find the original offset for the stock marks, then etch new ones onto the replacement.