Bill, on your wet sleeve models I think the concern was how the water tight integrity is maintained and perhaps the issue of corrosion/electolysis. Obviously there haven't been issues with the wet sleeve to speak of that we've heard, but I think the concept concerns some folks. Could you elaborate a little on how the wet sleeve setup works and how the integrity of a wet sleeve really isn't a problem? Thanks for chiming in on this. I don't have a problem with either design, but a little engineering input might educate all of us a bit...mainly in the area of cooling, water tightness, longevity, and corrosion...or any other category that you might think is helpful in understanding the difference between your wet and dry sleeves.

 

This is a very nice thread, as I've completed a successful suspension upgrade, and now the bike is deserving of more power. I'm at LEAST going to go 331 from Mr. Blue. Gotta save a little after paying for the suspension work, though.

 

As long as Bill is around, what about vibration.? How much more does the bigger piston weigh.

My thoughts on the bigger bores.
If the cylinder is heated when the sleeve is installed, the seal between the two will be good and tight. Once the sleeve is installed the cylinder is filled with water so it will never get over 212*f. It can't expand much and the heat is IN the sleeve carried away by water never to reach the cylinder (jug).

Corrosion is no problem as the right antifreeze is used. OR if the wrong antifreeze is used and changed every couple of years.

Still contemplating.... Go big or go home. I have seen no reports of fuel mileage of the bigger bore bikes. I use mine to commute, so appreciate the 62 mpg I am getting now even with re jetting and KDX snorkel.

David

 

I don't know if there are any actual reports around about your questions^^^^^

I have done a ton of research around the various forums about big bores for myself, that is my next mod. The info is out there, just not in one concise spot.

I have consistently read that with 351 kits, gas mileage is usually around 55 mpg with the stock carb, and closer to 50 mpg with a pumper carb.

Also, everything I have read about vibration says that a 351 kits adds a little tiny bit but nothing excessive. In fact, many say it doesn't add any at all.

Also, about longevity, someone on here has a 351 with like 22,000 miles on it. I can't remember who but that should answer any questions about its durability.

 

what's the power difference between the different big bore kits?

 

For what its worth, the weight of the stock piston on the 2009 was 185g. Bills 300 kit came with a Wiseco piston that weighed in at 236g. Sounds like a lot, but not a lot of extra vibration. I guess calculating the difference in rotating weight would have to include the wrist pin (49g), rings, and some fraction of the weight of the rod.

 

thanks sanpedro, It was posted in another thread the 351 piston was 244g. Anyone have any others please post them

 

I'm going with 331. Several reasons: I run in temps above 110 degrees on some very tough trails/hills at times, and I think the 331 might be a bit more prudent under those conditions. Also, it's the largest bore where it seems the stock carb still operates OK after re-jetting. I'd like to hold off on buying a new carb until a bigger tank option becomes available for the 2009.

My suspension upgrade is really nice, and the Corbin Seat is a MUCH better width for me. The bike is actually comfortable now! I think the 331 will allow me to ride uphill out of the valley into a 30-35 mph headwind while maintaining at least 60 mph without having lay down so tight that I'm under the paint.

 

I actually get a little better gas milage with my TM33 than I did with my CVK with the Stage 2 Dynojet kit and one size larger than stock pilot jet.

 

i got better fuel mileage when i when from the 250 cvk to the 351 tm33 pumper and full stain tune system, that in tough trails/hills rarely going below 6500rpm and i run in plus 45 degrees which is 113 in the old scale. i do run a fan but it doesnt really turn on that much more than the 250 did.