Well good old 2strokes:x ....

[CuRt]

Went up north for a couple days of riding got about 65 miles in and all the sudden I hear something well something went theres no compression piston looks okay just rings are bad when it was running you could hear it knocking bad so had another 10 miles back and no one had any straps so I just rode it back, anyone elses 83-84 Rs as reliable as mine? any reason to why it is like it is? really makes me wonder :x . Looks like its time for a 4stroke.


Curtis

[speed20]

it could possibly be your radiator or whatever....it might have been blocked or something like that....but i dont know why it would just up and have no compression....if your radiator wasnt working you would have locked it up.....:/

[Howdy]

it could possibly be your radiator or whatever....it might have been blocked or something like that....but i dont know why it would just up and have no compression....if your radiator wasnt working you would have locked it up.....:/

I can rule out the Radiator. 84 250r's are air cooled. ;)
Howdy

[Wickedfinger]

...beat me to it Howdy. I wouldnt be so down on the '83-84 R's just yet - they are great trikes, but you have to do your regular rebuilds or else things like this happen. It might be that the motor could have been overheating the whole time and never cought back up to cooling itself once you got rolling again. The aircooled R's kinda get a knock from pre and post detonation when any overheating occurs, but that usually clears up when you get out of the woods and get some air flowing over the motor. It sounds to me like you either have a really bad piston slap due to a worn wrist pin and excessive cylinder clearance or you might have actually let the wear get so bad that it has affected the rod and blown those bearings (unlikly though - you probably would have grenaded the motor). If it is a worn pin, the noise could be from too much play between the piston and the cylinder or a combination of the pin/cylinder and the rod is possible. Anyway, I HOPE its just a overheat problem or just a simple hone and an oversize piston/rings/wrist pin job. Maybe someone else has some other ideas too.

[CuRt]

If thats the case it had about 15 hours on the last rebuild I hadent rode it much since I got back from silver lake sand dunes seems pretty unreliable to me. It was pinging I knew it was hot so I was taking it easy on it the guys on quads would wait for me at stop signs stop and let it cool for a few mins take off down some roads 5th gear half throttle, I was running klotz and 87(only thing the gas station had). I think its time to rebuild it and sell it either a 85-86 250R, one with a cr250 engine with the power valves, a 350x, 250x with 350x engine.

Thanks
Curtis

[Wickedfinger]

.. what did your last rebuild consist of?.

[Curtis-Tecate3]

Have you checked your jetting, plug/piston color, any air leaks? There are plenty of variables other than it was just rebuilt Xhours ago and now it blew up etc...
As soon as it starts pinging then the ride is over. Keep running it and pay the consequences...

Curtis.

[CuRt]

My last rebuild was because the base gasket went and destroyed my piston, honed it out(honer with the little balls on it) new piston rings, gasket set, everything was still good, bottom of the cylinder was .001 off wiseco even said it was fine use it. Plug has carbon on it, piston has carbon halfway down it. Well if it starts pinging I should stop theres problems I stopped they were filling up on gas let them cool for awhile mine was cool to the touch started it and it was already pinging, so I dont know we were always stopping at signs for 5 mins or so and it would cool down.

Curtis

[HemiChallenger71]

Waht about your gas? you running high octane gas?? because it is required.

[speed20]

Howdy.....I know my 200x....and only my 200x...That post was out of pure stupidity....and i dont know why i posted that....but i will remember that the 83-84 R's are AIR COOLED...hehe

[CuRt]

I was running 87 it was the only thing that they had, friends 2001 all built ported polished, bored out everything done to it yz125 was running the same thing and he never had a problem.

Curtis

[Wickedfinger]

... 4 points down on the octane scale won't do that to a motor. I still think during your last rebuild you needed to go .10 over and not just give it a cross-hatch hone. The carbon down the side of the piston means the charge was getting past the rings - if it was just the engine overheating, you probably wouldn't have that - the piston expands quicker than the cast iron bore sleeve and would cause a siezure. Again without seeing it, I'd have to go with a piston skirt slap caused by a worn out bore. Was the carbon just near the bottom of the non pin sides of the piston and was there wear on that part of them and or the lower part of the cylinder?.