Wiseco Piston Kit 11:1

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yamaharider

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Wiseco Piston Kit with 11:1 compression. Anybody run them or have any reviews on them? Wondering if they're any good.
 
Kyle (Beastlywarrior228) just installed one in his I think he just finished break in on it
 
Which kit you thinking about getting? 349, 353 or 357? Just curious. I was thinking about going with one of those 11:1 before I decided on my kit.
 
I would like to stay with the std. bore. I was wondering if it would give me a boost in any power especially because i picked up a fcr 39mm yesterday for $50.
 
I wouldn't know how much more power your gonna get but that new carb should be awesome..nice pick up
 
I put one in mine back in January. Very nice piston. A little pricey, in my opinion. But, I find it to be a happy medium between the 10.25:1 Wiseco or 10.5:1 JE and the 12:1 JE.

You'll feel an increase in bottom end power mostly. It will pull harder through the gears with it. Just know that you will NEED to run 93 octane fuel. Or, 91 if that is the highest octane fuel in your area. Adding a good cam will help with the power improvements with this piston.
 
wish they came out before I built mine I had to drop the jug and mill the head to get 11.1
 
Ok. Because I'm really thinking about getting it just because i would like a little more power just because i am a bigger guy.

And I always run either 91 or 93 octane. I don't like running gas with ethanol in my toys.

Also quick question! I rebuilt the motor about 4 months ago. In that 4 months I've put maybe 200 miles on her. 2 weeks ago i was up by the pipeline in Breed, WI. I was in 4th gear accelerating to catch up to my cousin when my motor cut out and died. I tried starting it again but it sounded funny so i pulled the spark plug. I figured i'd do a quick compression test. It barely moved my finger... So i towed it back and last weekend i pulled it apart and the rings were shot. There was a little blow by on the crankshaft but nothing to worry about. But i drained the oil out so i could take it out of the frame and there was a bunch of metal in the oil. Looked like glitter. Is that normal after a fresh build or is there something else besides the rings that went bad. It also burnt a lot of oil which is why I'm getting an oil cooler. But is there something that i should check out. Next week I'm opening up the case to replace my timing chain but is there something that i should keep my eyes open for?
 
Yep Ed's right Kyle was the first I know to have got one for a 350, He bought it about 6 months ago. I have Wiseco 11:1 in a 660 but cant speak for the performance it would do for a 350 but Wiseco make great parts I can say that much.
 
So you rebuilt your engine and drove 200 miles without changing the oil? You should of changed it after the first tank of gas & then again after your first big ride & then again every 3 rides.
 
But with the first oil change after a rebuild; glittery is normal.
 
I'm sorry i should have clarified. I changed the oil 3 times before that. The first one had that glittery look to it. The second one had a little the third had none now this would be the 4th and it came back. Could that be just from the piston rings being cheap or not made right?
 
It wearing out that fast isn't normal. Either the cylinder isn't round anymore, or it went together dirty. There's no way it should wear out that fast.

Change the oil pump this rebuild. And I would be willing to bet that you will need a bore and hone so std bore is out of the question.
 
I just got it honed today from the local Yamaha dealer here in Green Bay,WI and they checked the diameter of the whole cylinder and it was in spec. So they honed it and it looks good now. There were only a couple of little scratches on the cylinder wall before the hone that you couldn't even feel so there was really no need to bore it.
 
Do you think the reason why it wore so fast was because i was having trouble getting the jug over the piston? I had to take it off and on a few times because the gasket kept moving. I had to replace the gasket twice while i was trying to get it on because it would move over the hole where the cam chain goes and it would tear.
 
Did you clean and then oil the cylinder? And Yamaha spec is only good for Yamaha pistons. Wiseco requires a much tighter bore then factory. .004" if I remember correctly. If the bore does match the PISTON, it won't last long. Now if your dealer is anything like the ones around here it still needs to be checked out. Check it yourself is the only way to do it right. And considering you have ran two sets of rings through that cylinder and they say its still in factory spec.. I call bs on that. Your lucky to ring it once without the bore going wack or oblong. That's my .02 and I've built 9 warrior motors and countless others so I should know what I'm talking about.
 
I did clean it after i got it back and oiled it. They said to clean it with that acid stuff i forgot the name of it. To measure it would a dial caliper be accurate enough or should i get something like a boring bar?
 
With a caliper you can only measure the ends of the cylinder. That won't tell you if it's round where the rings ride which is the whole point.

Take your old piston, remove the rings. Now use a set of fine feeler gauges and start with the .002" feeler and slide the piston beside it and check it around the piston, itf it's out, you will know.
 
I kinda lost you with the feeler gauge. I got the piston with the rings off so should I just take my feeler gauges and slide it down the cylinder with the old piston?
 
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