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trestunt30

1988 Suzuki LT250R Piston Replacement

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Hey quadcrazy im looking into but a suzuki lt250r but the guy said the piston needs to be replaced and he said it wont start. He is sale it for $500 dollars. Ifi do replace the piston do you all think it will run or are there more problems with it you think ?

Also i would like to say thank you to everyone who has helped me on this website i greatly appreciate it one love

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if you replace the piston, you will need to hone the cylinder out and take a micrometer reading. i know there are 3-4 different size pistons for the bike for honing and wear. you might have to adjust the valves after for it to start and /or carb work. thats all i have ... sounds like a pretty good deal btw ...

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So its worth it ? and he did mention honing the cylinder i dont know about a micrometer reading but ill look it up and read and watch videos i appreciate the response greatly.

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if you replace the piston, you will need to hone the cylinder out and take a micrometer reading. i know there are 3-4 different size pistons for the bike for honing and wear. you might have to adjust the valves after for it to start and /or carb work. thats all i have ... sounds like a pretty good deal btw ...

If he has a 88 LT250R than its a 2stroker Super easy to rebuild ! No valves involved !

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yes, easy to rebuild. but there will be a lot more than just a piston. if it has such bad compression that it will not run, it will need to have the cylinder bored oversize to get the cylinder walls straight. one of the problems, is as the cylinder wears (along with the piston) is the walls become egg shaped (top to bottom). in part because of all the ports (holes in which the fuel/air/oil mix moves thru the engine). and as the piston wears, and gets quite loose, it actually rocks enough to have actual metal to metal contact with the cylinder wall. much more then when it is new, and tight. this allows for even more, accelerated wear. now, the big deal, is, the cylinder can only be bored so far oversize. after it gets so large, it either has to be replaced, or bored very over sized, and a new sleeve installed, which will in turn need to be bored to a new stock sized piston. you will also need to replace the top end connecting rod bearing and piston pin. those are very important, and wear about as fast as the piston does. and all of the top end gaskets. finally, the bottom connecting rod bearing, will only last so long. if it is loose enough that you can feel ANY up and down play in the rod on the crankshaft, then a new connecting rod, pin and bearing will need to be fitted as well. that is called rebuilding the crankshaft. all of this together, is an expensive proposition. but when you are done, you will have an engine that will last a long time. at least as long as you do not forget to mix oil in with the fuel. 1/2 of a tank of straight fuel will ruin the engine! to replace the connecting rod, the entire engine will need to be torn down. and at that point, EVERYTHING needs to be looked at. every gear in the transmission, water pump, etc. etc. etc.. hopefully, you will be able to simply rebuild the top end, and be done with it, for now. but all of this is coming eventually. i am not trying to scare you off. but you should be forewarned as to what will come along down the pike. or, it may need it when you buy it. there is no way of knowing, until the engine is opened up. id did this kind of work for roughly 35 years, until i screwed my back up so bad i can no longer work. so i have a darn good idea what i am talking about. oh, just as an added side kick, there ARE valves in this engine. they are REED valves, in the bottom of the intake port, that help feed extra fuel/air mix to the engine, for added performance. they will need to be looked at as well. if there is the TINIEST of cracks in them, they will need to be replaced.

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