1984 250r project/ help

[oconnor65x]

so i recently purchased a 84 250r all complete but was sitting out in the rain for a couple of years. the dude we bought it from said it had good compression but no spark, when i took it home i pulled the plug and saw that it had killer spark. so i cleaned the carb and gas tank and put in some gas mixed at about 30:1 and within the first 5 cranks it fired up and reved fine. we also tested for compression and it seemed to be ok. but as it was running it was excessively smokey so we let it run for a bit thinkin it needed to clear out from sitting for a while but the problem never went away. and i noticed some oil dripping where the silence meets the pipe.. so my uncle thought it was the crank seal or something like that. and i was wondering if this was something that would require the case to be split or if there is any other possible problems???? :wondering:wondering thanks for the help,,,,,, joe

[yaegerb]

its a two-stroke motor....it will smoke and it will smoke excessively if you just let it idle. Take it out and run the bike...the higher the RPM, the less smoke you will notice. It is also common for oil to be seeping from where the expansion chamber meets the head and I have also see them drip oil from the silencer to expansion chamber fitting. You said the compression is "OK"...what was your final compression number?

[Poco Loco]

so i recently purchased a 84 250r all complete but was sitting out in the rain for a couple of years. the dude we bought it from said it had good compression but no spark, when i took it home i pulled the plug and saw that it had killer spark. so i cleaned the carb and gas tank and put in some gas mixed at about 30:1 and within the first 5 cranks it fired up and reved fine. we also tested for compression and it seemed to be ok. but as it was running it was excessively smokey so we let it run for a bit thinkin it needed to clear out from sitting for a while but the problem never went away. and i noticed some oil dripping where the silence meets the pipe.. so my uncle thought it was the crank seal or something like that. and i was wondering if this was something that would require the case to be split or if there is any other possible problems???? :wondering:wondering thanks for the help,,,,,, joe Also there is a chance the previous owner ran it too rich for years and I bet your exhaust system interior is coated in 2 stroke oil. The muffler could be saturated too.. This is common and no big deal. Ride the piss outta it and let er smoke. Buy high quality 2 stroke oil for it. Dont buy that junk at the auto parts stores. Get it jetted rite for your altitude and ride ride ride. That smoke will most likely get less and less till it looks like a normal 2 stroke exhaust. Dont let it idle for long periods of time. They dont like that.

[oconnor65x]

i didnt actually run a test but i put my finger over the hole and spun it over and it seemed to be fine it pushed my finger off and sucked my finger in. and i understand its gonna smoke but its smoking a bit to much even when in high rpms ill post a video if i get time too

[oconnor65x]

http://www.youtube.com/watch?v=a8DlagDyrJk&feature=youtu.be here is the video

[oconnor65x]

and im not to sure on all the jetting stuff im at like sea level maybe 50 feet above what jetting do you think that would be if u are familiar thanks for the help

[oconnor65x]

And for my situation when I give it higher rpms it smokes more... I understang how a two stroke works and acts

[manbearpig]

if you bought it from someone who ran it in your area or nearby elevations, you'll probably be just fine with your jetting. do like Poco Loco said, just ride ride ride. if it idles too high on its own with no smoke, then you have a leak and issues. if you just let it sit, it'll load up and will smoke a bunch. a good mix oil to run in your bike is Maxima Castor 927, Golden Specto, Klotz, and other castor based oils. your bike was designed in an era where castor based oils were the peak of 2 stroke lubrication technology so thats what should be run. 30:1 or 32:1 should be fine. if your bike always runs rich and you're fouling plugs left and right, check your reeds and reed cage. if the reed pedals done seal to the cage, itll run poorly in a rich condition

[yaegerb]

What was your final psi on your compression check? Have you performed a leak down test yet on the crank case to rule out a seal issue?

[oconnor65x]

What was your final psi on your compression check? Have you performed a leak down test yet on the crank case to rule out a seal issue?

I didn't run a legitimate compression check more so redneck rigged up way. I just put my finger iver the spark plug hole and it seemed to push and pull fine which made me think the top end was fine. And even if it was shot Its my understanding that eouldnt cause it to smoke more rhan normal.. maybe on a 4 stroke but not a 2 stroke.. in my video I posted it fired up on the first kick so I think top end wise and compression wise its fine.. and I have not I was going to pull the motor out either today or tomorrow... (tomorrow) but I'm pretty sure that's my problem I was just wondering if I had to split my case in order to change the crank seal