scotto- the Picco crankshafts are a little long for the Losi clutch nut with Losi's there are several things that i've found that makes the clutch nut come loose.
1). the clutch nut has some debris in it (left over filings from being machine during manufacturing) is usually the culprit.
2). the collet is bad , worn etc.
3). depends on what type motor , i know Picco's have a longer then normal threaded section on there crankshaft , and what happens is the clutch nut bottoms out just as it puts just barely enough clapping press. on the flywheel , and through some use or starting on starter box especially (sp?) when motor is tight or loaded up with fuel it over comes the inadequate tightness of the flywheel , in which case to solve you have to cut approx 1/4 inch off the threads of the crankshaft , then nut won't bottom out, but you want to investigate the problem and make sure what is happening prior to cutting your crank.
to get your clutch nut off may be a little tough since the flywheel is slipping , i've seen people put thinks in the exhaust port to stop the piston from going up i don't recommend that but if you do make sure it's something soft like a wire tie folded in half , the make a piston locking tool which i also don't like it overstress the piston and connecting rod , try to get the clutch nut off you may be able to use some channel locks and hold the flywheel with them since the flywheel is loose you may have to put some sideways press.on to bind the flywheel on the shaft a little to get the clutch nut off , Picco's cranks are a little too long cut about 1/4 inch off with a dremmel and put back on.
Last edited by purplerides; 11-22-2001 at 08:51 PM.