I have a 94 sport 400L. I just got done installing a new piston and rings, bored .060 over.
The clearance between the piston and the cylinder is .003
The electric start rusted out so i have to pull start it. The problem is that it is hard to pull, is this normal?
I did install a different flywheel. Once started the piston sounded like it was slapping against the cylinder...a continuous
ticking sound. Any suggestions?

 

mine seemed to have the same sound to it...

i did find one thing wrong with mine after extensive work.... the water impeller housing sits on a shaft... the bearing on that shaft had completely rusted over due to a slight leak in the seals... this wasn't the sound though... after all of this the impeller began to loosen... in the end the impeller had a egg shape to it and it was bouncing around and hitting the housing around it... its not an easy thing to check but that was a large part of the sound i had... after replacing all of that she quieted down a bit... but i still have a little tinking when she idles too... but ya give it a little gas and it goes away.... if that impeller isn't a problem for you then thats all i got... sorry i'm not horribly experienced... just my 2 cents.

 

for some reason the wiseco's slap around, well the whole 400 motor tends to slap around. It probable is piston slap I noticed the noise two and had others advise me that is what it was and not to worry about it. its been about a year with no problems.

The only reason I can think of it being hard to pull is if the plastics bushing for the pull cord is bad or now the machine has more compression being a fresh rebuild. Did you lather the cylinder in 2 smoke oil before firing it up?

 

the knocking noises most people hear on the 400 motors isnt anything to worry about.i always thought it was piston slap but i figured it out.whats making the noise isnt piston slap,its actually the gear on the counter balence and the gear on the crank making a slapping noise as they hit together..im not saying thats what the noise is from on all the 400 motors,but most of them im sure thats what it is..

 

Thanks for the info. I did end up replacing the counterbalance and both bearings, actually had to. Both ends of the counterbalance where completey broken off. Not sure how that happened. This fixed the overheating prob. The ticking/slapping has subsided some - who knows why though - and I did notice a slight scraping from the impeller from it rubbing on the water pump housing. Couldnt tighten it on any tighter so i just shaved a little off of the impeller. Not sure if this was a good thing to do but it works fine. I did put oil in the cylinder, a very light coat. I went ahead and bought a starter and gear drive for it - started right up. Easy to pull start now too.
The motor does shake still - like riding a giant vbrator....but this could be because the front bushing is busted, titling the engine and I'm missing a magnet off of the flywheel. Both parts on order....