lifan 140...random noise

BlackHornet · Jul 22, 2014

Hey guys, Ive got a Lifan 140 "monster" in my bike. 4-up tranny.

when I lean the bike to the left, I hear a 'tapping' noise, when I straighten it back up, it goes away and when I lean to the right, its not there. I just adjusted the valves in hopes that those could be it, but no luck. I checked the cam sprocket to see if maybe it had come loose from the cam but it was tight as well as the chain. The noise didnt used to be there and I havent done anything to make it worse, anyone experience this? The clutch grabs and cycles fine, but what else could it be on the left side of the bike?

my67xr · Jul 22, 2014

hi, Welcome to Miniriders,

make sure you drop by into our Introduce Yourself thread and say hello there too.

how much oil is in your engine ? and how old is it ?
how many km's have been done on the engine ?

cheers, craig

BlackHornet · Jul 23, 2014

Will do! thanks for the welcome!

Oil was full and "fresh". The bike sat for a bit and when I parked it, it was fine. After I posted this, I went and pulled the crank case cover and so I drained the oil. I didnt take a anything apart but I did look at everything in there and nothing was loose or out of place. I put it back together and put fresh oil in it and it still made the noise. As far as kms....not too sure, quite a bit. The weird thing is that it didnt make this noise when I parked it. I havent taken a compression tester to it yet but it starts up first kick and still rides as if it has all of its power. Does anyone know what the compression should be?

my67xr · Jul 23, 2014

anything upwards of 150 psi should be fine, even a bit lower

when the clutch cover was off, did you try moving the clutch housing?
they usually have a bit of side play.

BlackHornet · Jul 23, 2014

Ok, I will get a compression tester on it ASAP. its 12 at night here right now...tomorrow is a new day. Thanks for the reply!

rotn50 · Jul 23, 2014

Check the magneto bolt is tight mate, I have seen a slightly loose magneto contacting the magneto cover a few times, also the timing chain roller guide behind the cylinder wall maybe perished on one side causing the chain to temporarily contact the wall of the cylinder on the left side.