[quote]ORIGINAL: tremor38

"I guess Shadetree is probably the only one with the KK kit who is near stock compression ratio....interesting. The literature with myWiseco 292cc piston stated11:1 compression ratio right in theliterature."

I'm actually running around 12.5/1 or a little under. Luke Heaney at Luke's Racing CC'd the head and compared that to the cylinder volume and came up with over 13/1 before modifying the head to improve flow and lower compression. His theory was that removing the eyebrows and polishing the surface would yield more HP in the end than leaving the compression at the maximum. Also, running pump gas was important and lowering the ratio made that possible.

On another note, and not to add to the confusion on another thread, but I like the stock gear ratio with the big bore. I'm even thinking about going to a 15 tooth countershaft sprocket. Engine wear is a direct function of how many times an engine does it's thing. Of course heat and load are significant factors too, but turning an engine, say 10% faster causes just about 10% more wear over the same amount of time. Smaller sprockets also wear faster because they're working harder (producing more leverage on the rear wheel) and the chain is turning back on itself much tighter. Not to mention that there are fewer teeth to grab, causing more load on each remaining tooth. You can always downshift, but you can't shift up to a gear you don't have...say seventh...
For low speed work, trials riders slip the clutch. We can do that too when first isn't low enough. It provides more control than merely slogging in first with chain ****** causing rough power delivery, etc. That's enough on that subject for now, but it's worth thinking about. Ultra low ratios cause the engine to wind out quickly, often making us think we're accelerating faster than we really are. Helps some and sometimes in the right situation, but it's no silver bullet.

Bill Dragoo
Norman, Oklahoma

 

I also prefer stock gearing with big bore. Let us know how it goes if you get the 15 tooth CS. I have seen it listed for our bike, but I think there is a problem getting it to fit under the stock cover. Nothing unsurmountable I'm sure.

 

I'm currently running the 13/45 gearing and was planning on putting the 14 back on after the BB kit is installed. If the BB kit does it's job then there should be no real need for the lower gearing.
I'm starting to get anxious. I'm looking out the door everyday waiting for the big brown truck!

 

Sorry VFR I called UPS and had the package re-routed to my house, I hope you're not too disappointed there.[8D][8D][8D]By the way what's a BB? That means Blackberry to me.

 

Question: Tremor- what fuels are on base anymore? 12.5 + or - can still run on 89 for most rides. But like you mentioned, timing needs to be considered. I have not played with the klx on this, just my 10r. But I am right at 13:1 using 89 oct.

 

Hey, Gary. We'll have to see how the bikes perform side by side at the Eureka Springs, Arkansas Dual Sport ride in March. If you're setup is as close to mine as it sounds like it will be, the gearing will be easy to evaluate.

Bill Dragoo
Norman, Oklahoma

 

Did you guys go with 11:1 on the 33x big bore? I though one company I talked to said they provided a 12.5:1 piston. From my past experience, high compression pistons raise the power across the entire rpm band...all other things equal.

 

I'll have to start dieting! I outweigh you by probably 35 lbs. so I need to get slim and trim so that I don't embarass my bike.

 

Gary,
No problem. We can just see how badly you beat me...switch bikes and see how bad you beat me again. Then we'll know which gears are best! I'll race you to 100 mph too. With my Bill Blue, WER steering stabilizer, I'll still be going when you fall off! Kidding, of course. I'll probably fall off your bike when I try to find top speed with your gearing.

Rick,

My piston is a JE 12.5/1. You're right in that higher compression usually yields higher HP, but we're trying to keep these sleds from flying apart between our legs...and pump gas is nice too. So, we tend to err on the side of smartness(we fudge a bit to compensate for our ineptitude) and lower compression enough to stopemfrompingin'. That's my story and I'm sticking to it.

Bill Dragoo
Norman, Oklahoma

 

I am not sure Deej, but I think he is talking about taking the klx to a bed and breakfast.

On a side note about gearing and engine wear. I will agree that the faster the engine spins the more it will wear. I don't think that the lower gearing is to much to worry about though, the klx300 comes with 14/50 from the factory which is lower than what most are running on here. If it was going to cause a problem with rapid engine wear I don't think that Kawi would have put it on. I do understand though, that with the BB you don't need the the lower gearing to get the low end torque and most of us are running at highway speeds for longer intervals then the klx300 was intened for.