2-stroke Compression?? hard to start

[PowerTrike]

My Scrambler sorta has me, well scrambled. Old polaris fuji 250 2-stroke seems to run great once its started but is often a real PITA to start. Sometimes is starts on first or second pull but conditions have to be just perfect. Often won't start when warm. Want to get it more reliable for hunting this fall. She seems to have pretty good power once its started but the motor might be getting tired (might be hard to tell with the variable clutch?). I think its on the original bore. Compression test only shows about 100psi compression. I don't think these motors came with very high compression from the factory (only calls for regular grade gas) But would 100lbs cold cause really hard starting??? Has good spark and is getting gas, could it have anything do with seals? Anyone know what the compression should be? (I've looked, can't find)

I'm not too concerned with regaining any lost power now but I want this thing to start in under 1000 pulls! Any posibility i could just thow on a new set of rings to try to bump the compression up a little for a "quick fix" or should hold out for a fresh topend?

Thanks for any help given. :beer

[TimSr]

I dont know the compression specs on that machine, but 100psi sounds awful low to me. I cant imagine it being less than 150-200. Is this a trike?

[Somekindofjerk]

100 will fire and run but the desirable pressure is as said above 150-200. if your going to put new rings in you really should buy all new gaskets. otherwise you take a big chance of springing a leak. check simple things first though, like hom much fuel your getting and the ratio, i like running a 38-40:1 in my sled for good lube but allso good throttle response.

[PowerTrike]

Yes this is on a trike, I'm haveing a hard time finding compression specs. I probably might as well drop in a new std bore piston/rings and a fresh set of gaskets. It does seem to run pretty good once its going though, Just sometimes won't start! Its oil injected so I can't really mess with the ratio. I believe my sled checked out at about 160psi per side last time i checked...

[MTS]

Yes this is on a trike, I'm haveing a hard time finding compression specs. I probably might as well drop in a new std bore piston/rings and a fresh set of gaskets. It does seem to run pretty good once its going though, Just sometimes won't start! Its oil injected so I can't really mess with the ratio. I believe my sled checked out at about 160psi per side last time i checked...
Look for spces for a polaris trail boss i think it was...with the 250 same motor...probably easierr to find.

[PowerTrike]

Yeah I usually always search "Trailboss" when I need stuff for this trike. I'm pretty sure I found the compression specs: only 110-120 PSI Looks like I'll be ordering up a gasket kit and a new set of rings at mininmum. Probably new piston too.