I got this 200cc motor and they told me it needed a piston and rings and that it was board out but they didn't no what size. I took the jug off and mesured the piston and it said 66.82. So do I get a 66.80 piston or what I don't want to get the wrong one
what size piston do i get
- Thread starter danstafford
- Start date
take it to whoever is going to be boring it and they can measure and tell you exactly what you need. also if i was you when it does come time to order. call rjatv and get a weisco piston
Piston sizes go by .25mm, so the next size up would be a 67.00mm, also referred to as being .040 over (in inches). As surf said, take it where you will get it bored and have them tell you to be sure, as if the bore is to messed up it could possibly require a bigger size.
Cylider looks great as for the piston it roach. Cylinder just needs a hoaning. I just make sure cause. Pistons are cheap on ebay
Any reputable shop should be able to mic it and let you know what oversize piston you need, at which point you can purchase said piston from wherever. As others have mentioned, it may need overbored.
If you are in doubt, get it overbored. Loose bores cause broken skirts, and I am currently doing a full rebuild (with new cases) due to a broken skirt. The price? A lot more than a bore and piston.
If you are in doubt, get it overbored. Loose bores cause broken skirts, and I am currently doing a full rebuild (with new cases) due to a broken skirt. The price? A lot more than a bore and piston.
Plus your measuring device is off. There's no piston 66.82 , unless it was a 67 worn down about .15.
I had it remesured its a 67mm I'm going out today and get one. Do a quick hoaning to it and be ridin dirty. That all I got left to do
It can LOOK great but if your cylinder is .020 out of round .....you just wasted money....take it to a machine shop they wont charge for the information...and as surfjag said go with rj_atv on ebay for your piston kit Electrical Ignition, Snowmobile Bearing Kits items in rj-atv store on eBay!
X2 on machine shop. With calipers you only measure very end of cylinder where there is no wear. Here is a better way, tho it should be front to back and side to side, two spots not three
http://www.blasterforum.com/do-yourself-20/how-measure-your-cylinder-bore-pics-15642/
Here is best tool to use
Dial Type Cylinder Bore Gauge Kit 2-6in Range
Considering you are looking for about .003 clearance you see why accuracy is upmost important.
http://www.blasterforum.com/do-yourself-20/how-measure-your-cylinder-bore-pics-15642/
Here is best tool to use
Dial Type Cylinder Bore Gauge Kit 2-6in Range
Considering you are looking for about .003 clearance you see why accuracy is upmost important.
Got the cylinder messured it hasn't bad at all just needs hoand. I took it a friend I hadn't seen in yrs he has his own shop. And got onther motor stock he's go boar that one for me to but I'm not going that big with that one I found a rolling chassis for 100 bucks that ones gona be my daughters. I thank you guy for the info. Be safe riding but ride tires off
I just sent my jug here. They did an amazing job. They also milled my head for $30 and did a casting flaw clean up port job for $50. As soon as they received my package they called and confirmed all my requests. They called back in two hours saying it was done and that it was shipping out. Very good quality work too. Very pleased.
YAMAHA BLASTER CYLINDER BORING SERVICE With New Wiseco Piston Kit !! YFS200 | eBay
YAMAHA BLASTER CYLINDER BORING SERVICE With New Wiseco Piston Kit !! YFS200 | eBay
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