Hi guys. First post here..my buddy recently purchased a '99 sx500. Higher milage but apparantly the top end was done about 800 miles ago. Yesterday at the end of the day it started running on 1 cylinder, checked the pto side plug, electrode was smashed and had a lot of aluminum bits in it. It was pretty mild outside, and we were driving fairly leisurely.
So first off we have to figure out WHY it went, but after that, what kind of pistons do most of you guys use on the 2 stroke twins? I'm a skidoo guy and I know a lot of people are partial to Cudney and oem... is there a particular brand with the Yami twin that we should be looking at, OR a brand we should be staying AWAY from? How are SPI pistons in these sleds? Are the cylinders cast iron or are they Nikasil lined?
Thanks a bunch. I"m sure I'll have more questions once we take it apart and look for the cause. Carb boots look new, and it was running great, we were all using the same gas with ISO. So hopefully its not the crank seals or something
Matt
So first off we have to figure out WHY it went, but after that, what kind of pistons do most of you guys use on the 2 stroke twins? I'm a skidoo guy and I know a lot of people are partial to Cudney and oem... is there a particular brand with the Yami twin that we should be looking at, OR a brand we should be staying AWAY from? How are SPI pistons in these sleds? Are the cylinders cast iron or are they Nikasil lined?
Thanks a bunch. I"m sure I'll have more questions once we take it apart and look for the cause. Carb boots look new, and it was running great, we were all using the same gas with ISO. So hopefully its not the crank seals or something
Matt
shavedheadedyamaha
New member
the cylinders are lined and if it where me i'd use yammie pistons... i just pulled the pistons out of my vmax last night and it was the same exact problem as what you had chunks on the plug.... mine was due to me not cleaning the carbs and leaning one out very badly... check and see if one piston is shiney and the other black..... thats a lean out "mine was like that"..be sure to get em honed..... well.... let us know..... good luck....
ExpertXViper
New member
Only use Yamaha pistons, you wont find anything better.
yamyrider
Active member
YAMAHA OEM only....there is no better substitute.
daman
New member
OEM yamaha pistons and rings!!!!!!
you need to figure out whay she burnt, clean carbs WELL,check jets/needles pilots put to stock(if stock), tech section has all that info,do it right do it once!!!!!
post back with more Q's if need be......
you need to figure out whay she burnt, clean carbs WELL,check jets/needles pilots put to stock(if stock), tech section has all that info,do it right do it once!!!!!
post back with more Q's if need be......
horkn
New member
Round ones
lol
lol
daman
New member
^ lol
horkn said:
Haha, yeah, better than whats probably in there now
.Thanks guys, I'll let him know to go with OEM. As for finding the cause, thats what is puzzling me, this one is kinda strange as conditions were great, everything looks fine so far. Oh well we won't know till we pull it apart wednesday night and check it all over. Hopefully it will be something obvious.
I'll post back once we get it apart.
Matt
