I bought this non-running quad off my neighbor for $200. I put in a new plug and it has a good blue spark. I cleaned the carb and I now seem to be getting fuel to the cylinder (slightly wet plug after turning it over). I have not checked compression with my tester, but the old finger over the plug hole indicates decent compression. I will be testing the compression this weekend. Can anyone tell me the acceptable compression range? What else can I do to troubleshoot this problem?

 

Wow! 40 views and not one guess?

 

Have any idea why it was parked ??
Those old units were known for the intake valves tightening up and the main jet needle rattling out of spec, making them run rich.... Occasional ignition box issues. Myself, I abandoned compression tests as diagnosis about 25 years ago. Engines which I am unfamiliar with, I pull a cylinder leakage test to see where I am at for a foundation, before diagnosing it's issues any farther.. Lets me know what I am up against other than carb or electrical issues which may be at hand

~ Gimpster ~

 

Sorry for the delayed response, my street bikes have all began to act up....at the same time! those old 70's jap bikes just require some TLC every now and then.

I don't know the history of the bike. I bought it from my neighbor who bought it from someone else non-running. I have heard of leak down tests. Do you have a link that would explain the process? I was going to sell the bike off for parts just to get my money back, but everything I read about this model says it's a pretty solid machine. I hope to have time this weekend to work on it some more.

 

I would get rid of it....having owned a 200sx myself, I know that they don't handle well because of a poorly designed front suspension, and the brakes are crap.
I realize you only spent $200, but before you tie up more money and time fixing someone else's problem, you might find a clean used 1995-2000 TRX300 (or better yet a trx300ex or 400ex with disc brakes) as they have significantly better designed suspensions

 

Anyone use an aftermarket sprocket to replace the stock one????