83 250r Locked up PICS--*FIXED!

[smyers33]

Went on a ride today and the R locked up in 2nd pinned. I tried to kick it and it didn't budge. I let it sit for about 5 minutes then tried to kick it, and I could, but there is no compression what so ever. I just got this R a couple weeks ago, from ebay. I don't know if I should contact the seller, or what. This is my first 2 stroke, and I guess it needs a top end rebuild, but I have no idea how to do it. Anyone know what happened? Does this happen to the air cooled models often? If so I need something else. It really pisses me off though because I just got it 2 weeks ago! What should I do?

[Louis Mielke]

I would assume you were running mixed gas correct?

It probably was just tired and you happened to be the unlucky guy who owned it at the time. These bikes are 20yrs+. Only the very lucky pickone up thats super low hours. Yours probably just needed rebuilt. NO worries, everyone here on the board will help you out.

[p26575r16]

The air cooled models are very inexpensive and very easy to rebuild, and if done right it will last you a very long time. It sucks that it blew up, but if you rebuild it, at least you know what you've got.

[smyers33]

Yes I was using Klotz super tech. 32:1. When I pulled the head, It was the first time I seen the plug. It was a Denso, I can get the #'s if needed. Got it took apart... The cylinder doesn't look too bad, Gonna need a new piston. When I pulled the carb off there was a little razor blade type thing in the reed cage. It was just laying in there not screwed down or nothing. Also isn't there supposed to be 2 of those things? Could that of caused it to do this? First engine build and tear down here so any tips on taking the circlips off of the wrist pin. I got one out, but still can't get the other one. I don't even know where to start. Here are some pics.

[slothminx]

Good oil at a good mix ratio. You might have developed an air leak somehow, or the carb got plugged up.

Now what I dont get is WTF the little blade thingy is?! Im almost certain that doesnt belong in there lol.

With the circlips, use some needle nose plies grab one side and just twist the thing in on itself. You will get new ones with the piston kit

[gizmo_22]

from the looks of it that little blade thingy is a razor blade for scrapers, looks like somone had it apart before and forgot to take it out... probably caused you to run lean and lock it up... not very fun. But im sure youll have it back on the trail in no time.

[smyers33]

Here is a pic of the blade looking thing, for some reason I thought it had something to do with the reeds.

[Howdy]

That is a razor blade for scrapping gaskets off. In no way should have it been left in there.
Howdy

[smyers33]

Well damn, lol! So... I need to hone the cylinder. I don't think it needs to be bored, it's not that bad. Get new piston and rings.... New gaskets. Which reminds me is there supposed to be a gasket between the head and the cylinder, because there wasn't when I took it apart. Any recommendations on where to get all this stuff? I'll prolly just go to denniskirk.

[Xowner]

ahhhhhhhhh there was no head gasket???? thats a big no no ! wow that motor builder sucks not only did he leave the head gasket out but he left tools in the motor. as far as the gasket the place you ordered your piston from should be able to get you one. also order the complete gasket kit if you can afford it as you never know when you might need one for the bottom end never know it might save you a day of riding !


Good luck man

[smyers33]

Alright I haven't ordered anything yet, since I don't know the measurement of the cylinder. Anyone know a good place to get a hone, and what kind to get?

[SYKO]

you WILL have to bore the cyl, you wont be able to get away with just a hone job.. a decent bore shouldnt be no more than 50 and make sure they now that there needs to be more clearence becouse its an aircooled motor!! what kind of piston did you order?? wiscoe?? the honest truth is you need to take it to a qualified cycle shop to let them check it out. But dont let it bring ya down that you just got it, Ive had worse!!! its just one of those things!! and before you take the cir clips out of the piston put some clean towels on top of the crank!!!! or they may fall into the crankcase and get stuck in the crank!!!

[Lomax]

Sand the top of the piston to see what size you are at now. There should be some number stamped in the top I.E. .40 or .10, something like that to indicate the size. If I was you I would bore to the next size up and go from there.

[200x Basket]

that cylinder will need bored!!!!! There is no way you got that lucky. take the cylinder to a machine shop that does motorcyle engines and ask them to measure it. (you can take it to a bike shop but they will take it to the machine shop and charge more). goto www.denniskirk.com and get a gasket kit. only get the top end, there is no need to waste the extra $$$$. get a cast piston not forged.

[Somekindofjerk]

Ontop of the piston there are numbers.. take some very fine sand paper and sand the top of the piston a little bit with it if you cant see them. When you have them get on www.denniskirk.com and search that number. There may allso be another number like .50 or .25 or another number.. .that is an overbore number. There will be a longer part number though that is what you need to search for on the website.