Magnum Big Bore 290cc. Who's got one.. is it reliable?

Looking at doing a full rebuild on an 01 YZ250F with a smoked crank. the jug and piston look good and I will be reusing those until I get the $$ to buy a new topend. I have all the parts for the rebuild on the bottom with a hot rods bottom end kit. (made in Taiwan by the way)

So now I am trying to decide what big bore to get when the time comes. I am heavier at about 200lbs and ride woods only. I think the 290 is just what I need. So now question is.. which kit. I like the price point of the MAGNUM jug with the 2 compression ring wiseco piston..i am leaning in that direction dependent on one thing.. I have heard of some instances of Head gasket leaks?? can any one validate this.. ?

I called lukes and he told me that a wiseco kit might be a better option if that is something that is a major concern of mine.. I am just not sure. is it worth the EXTRA COIN?? I See the the kits they are running have a crush ring to help prevent issues with head gaskets. But he also said they are kind of going away from those too.

I would like to hear from some actual big bore owners.. and tell me you thoughts.. Is a little copper coat on the gasket all that is needed? I would also think that by upping the Compression ratio.. to 13.1 etc the head bolts might need a little bit more torque because of the extra compression? wondering if that is the issue with head gasket leaks OR if it is a matter of less surface area because of the added bore diameter...

can you run pump gas at 13.5:1?

thanks for you thoughts..

Thumper racing sells a 315 kit. Stroked crank, BB jug and cams. he warrantees his work and will build the motor based on your riding conditions/skill level. he also provides tech support if you have any questions/problems. The YZF 315 hauls the mail!

thanks but I am going to pass on that. I considered it but decided to go with something a little less "committal" and also budget friendly. the I am pretty sure the315 would need a balance.. and well more $$$. I already bought the stock length crank. So 290 is what I am looking at.

he sells 290 kits also.  much cheaper than the 315 since you dont need the crank or cams.

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