need help!!!
- Thread starter theslowz
- Start date
If your looking for reliability go for the stock stuff. Ive never tried Wiseco but they are supposed to be good too. Good luck with the rebuild!
I much favor the durability of a Wiseco forged piston over the stock cast piston. There are a few other good piston offerings out there but IMO Wiseco is the best.
Wiseco is best. I've heard cast piston's don't hold up very well. The forged Wiseco piston is best. last long time and reliable.
the skirts on the oe style piston tend to get warm an when u get cheap metal warm itll break an then u have a huge problem. thats y the forged piston are heat tempered an made from a better quailty metal so you wont have that problem. hell with the last rebuild i used a wiesco forged piston an when the engine died due to sucking in water and mud an seized the rings the piston was ran for a whole year an it looked brand spankin new yet. just the rings where shot.
I also agree with Wiseco as a solid choice for a replacement piston. Get a forged piston, even if you opt for another brand. Wiseco has always had a good reptuation for quality. As for the cylinder, get it mic'ed out. As in, measured with a bore gauge. If the cylinder is within factory spec and the bore has not become tapered or 'egged out', you can just hone the cylinder and go with a new piston and rings. However, a well-run engine will almost always have some wear to the cylinder.
What to do? Have the cylinder bored. Wiseco makes Blaster pistons in at least 3 oversizes. You will have to bore the cylinder out if it has wear marks, scratches, scoring, scraping, or 'bar-code' wear patterns. Get a trusted machine shop to do this work. They'll take your piston with the cyl. and make sure that the cylinder is bored to the proper spec.
Just a word of note: If you're trying to keep the best possible reliability with your engine, don't bore the cylinder out any more than necessary (ie, only go .020 over on a stock cyl, .040 over on a previous .020 bore, etc...) The farther your bore the stock cylinder out, the hotter it will run. This isn't a big concern, as Blasters seem to run Ok even on 240 BBK's, but I thought I'd mention it. ALSO, check the crank and rod while you're in there. If you want to have the cylinder ported, it can be done during the rebuild. Porting will bring on more power, but you will have to pay a lot more for this service than for just a simple bore job. The engine will run fine, even if it is not ported. This is popular performance upgrade during a rebuild. It is NOT required.
Good Luck! Once you get your new top end done and put on, just take heed: I know the temptation is there to crank it up and take off. Easy, fellow ripper!! Break it in first. Jet and tune the carbuetor. Then, let 'er loose. This will ensure that your fresh engine lasts.
What to do? Have the cylinder bored. Wiseco makes Blaster pistons in at least 3 oversizes. You will have to bore the cylinder out if it has wear marks, scratches, scoring, scraping, or 'bar-code' wear patterns. Get a trusted machine shop to do this work. They'll take your piston with the cyl. and make sure that the cylinder is bored to the proper spec.
Just a word of note: If you're trying to keep the best possible reliability with your engine, don't bore the cylinder out any more than necessary (ie, only go .020 over on a stock cyl, .040 over on a previous .020 bore, etc...) The farther your bore the stock cylinder out, the hotter it will run. This isn't a big concern, as Blasters seem to run Ok even on 240 BBK's, but I thought I'd mention it. ALSO, check the crank and rod while you're in there. If you want to have the cylinder ported, it can be done during the rebuild. Porting will bring on more power, but you will have to pay a lot more for this service than for just a simple bore job. The engine will run fine, even if it is not ported. This is popular performance upgrade during a rebuild. It is NOT required.
Good Luck! Once you get your new top end done and put on, just take heed: I know the temptation is there to crank it up and take off. Easy, fellow ripper!! Break it in first. Jet and tune the carbuetor. Then, let 'er loose. This will ensure that your fresh engine lasts.
Yamaha Blaster .020 Wiseco Piston/Gasket Engine Rebuild:eBay Motors (item 120454273367 end time Dec-28-09 08:24:04 PST) with this kit do i need to take the block to a machine shop to get it bored out? idk what the stock bore is or nething thanks for everyones help
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Take it to your local atv shop,yamaha or another if possible
Like here we have a yamaha and a "Fletchers"
Some of you might have heard of fletcher,famous husk 510 4 stroke rider
They will measure it and tell you the current bore size anf they should bore it 5 more over if needed,then hone and the place that i took mine to ordered my piston for me,
Wesico forged ftw
Like here we have a yamaha and a "Fletchers"
Some of you might have heard of fletcher,famous husk 510 4 stroke rider
They will measure it and tell you the current bore size anf they should bore it 5 more over if needed,then hone and the place that i took mine to ordered my piston for me,
Wesico forged ftw
I have just one note to add here. If going with a forged piston of any brand you need to pay more attention to warming the engine up by lightly revving the throttle. Forged pistons expand a little different than cast and can "cold seize" if not properly brought to operating temperature before being ridden. That is the only thing remotely better about a cast piston, it will hold up better for a rider who likes to romp on a cold motor.
