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LA Sleeve 300 Big Bore for YZ250

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I have a wasted 06 YZ250 cylinder that needs to be plated and I'm considering the LA Sleeve 300 kit. Is anyone here running one of those? If so, what's your impression and how's your bike set up (jetting, pipe, exhaust. etc..)?

Thanks!

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I wouldn't sleeve a modern cylinder, but that's just me. That chit is from the dark ages. This is a pretty old thread, and Tom Morgan is the 'name' behind Millennium and Eric Gorr has gone back to his own shop. You might also check with Harris Performance.

I'd call one of the plating shops and get them to repair it. They can do pretty amazing repair work, and the only hang-up is if you need to ride right away. If you've got time, I'd definitely get it repaired and plated. If it were me, I'd probably get it done back to stock, just because I like/love the stock YZ power.

If you get the BB and discuss with Tom or Eric or Harris, just be clear with what you want.

If you live/ride/race in SoCal and you're half decent speed, you'll want something that still spins up quickly and has good linear and long power. A lot of the BB kits and advice you'll read here will work better than stock in an offroad situation because the bike has a bigger/heaverier piston which will spin up less quickly and grab traction. In SoCal, especially for MX or GP MX, you're in third and fourth a lot of the time, and you'll appreciate the stock style of power. Revs quick and rips.

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10 hours ago, Swappa said:

I wouldn't sleeve a modern cylinder, but that's just me. That chit is from the dark ages. This is a pretty old thread, and Tom Morgan is the 'name' behind Millennium and Eric Gorr has gone back to his own shop. You might also check with Harris Performance.

I'd call one of the plating shops and get them to repair it. They can do pretty amazing repair work, and the only hang-up is if you need to ride right away. If you've got time, I'd definitely get it repaired and plated. If it were me, I'd probably get it done back to stock, just because I like/love the stock YZ power.

If you get the BB and discuss with Tom or Eric or Harris, just be clear with what you want.

If you live/ride/race in SoCal and you're half decent speed, you'll want something that still spins up quickly and has good linear and long power. A lot of the BB kits and advice you'll read here will work better than stock in an offroad situation because the bike has a bigger/heaverier piston which will spin up less quickly and grab traction. In SoCal, especially for MX or GP MX, you're in third and fourth a lot of the time, and you'll appreciate the stock style of power. Revs quick and rips.

Piston weight isn't always what you think it is. A number of years ago one of the admins on this site (RCannon) compared the weight of an OEM YZ250 piston to  Wiseco and found the Wiseco to be 28 grams lighter. I compared the weight of the standard bore Wiseco to an EG295 Wiseco piston and found the EG295 piston to be heavier by 34 grams. This would mean the 295 piston is only 6 grams heavier than stock. In this case you statement about the heavier piston seems to be misleading as 6 grams is virtually nothing. Our experience with the 295 is that it revs just as quickly as a 250, it's just a lot more powerful with the mx porting.

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