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Smoking 2's

93 yz 250 power valve interchange

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On 4/14/2019 at 2:34 AM, Smoking 2's said:

Just that cap itself, where the valve hits. My valve had a bit of wear but the cap was wore 1/4" almost. 

wow thats quite a bit.. kinda scary too when the more it wears the closer it gets to the piston!!!  il take a picture of my old cap and post tomorrow its wasted! i managed to get a brand new oem replacement one for about £90... did you weld your cap up and reshape?? what did you do with your valve? 

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1 minute ago, Kxracer91 said:

wow thats quite a bit.. kinda scary too when the more it wears the closer it gets to the piston!!!  il take a picture of my old cap and post tomorrow its wasted! i managed to get a brand new oem replacement one for about £90... did you weld your cap up and reshape?? what did you do with your valve? 

I was able to get a used valve thanks to moto367 and a good used cap off ebay. Yeah it turned enough to hit piston. Mangled piston, broke PV in half but it still ran LoL

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20 hours ago, Smoking 2's said:

I was able to get a used valve thanks to moto367 and a good used cap off ebay. Yeah it turned enough to hit piston. Mangled piston, broke PV in half but it still ran LoL

ahh happy days! any damage to cylinder head? my heads ruined lol not quite sure what happened with it but she was still running too.. i decided to take a look at the noises it had been making thinking it was detonation and well turns out the whole motor needed rebuilding... heres some pics 

20190416_203312.jpg

20190416_203329.jpg

20190416_204600.jpg

20190416_204533.jpg

20190416_204514.jpg

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1 hour ago, Kxracer91 said:

ahh happy days! any damage to cylinder head? my heads ruined lol not quite sure what happened with it but she was still running too.. i decided to take a look at the noises it had been making thinking it was detonation and well turns out the whole motor needed rebuilding... heres some pics 

20190416_203312.jpg

20190416_203329.jpg

20190416_204600.jpg

20190416_204533.jpg

20190416_204514.jpg

I'd say that cap was wore out and getting danger close lol. Was your PV still good?

Looks like it was blew up once before also and all those dings are probably from pieces of ring or bearing hitting it. I wouldn't worry alot about the head, clean it up real good it'll run fine.

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