With all things being equal yes the 686 will out run the stock bore, theres no replacement for displacement but still doesn't mean you can't have a very fast stock bore

 

28cc isnt a big change in the displacement of the engine, it does add a few more ponies, but not enough to say that 686's will beat stock bores because i have .5mm bore which is basicly stock bore and i have beat plenty of 686 bores with stage 1 hot cams and 11:1 pistons.

 

That was my 57 hp bike at 4SW II. I have beat some Trinity 686 bikes. I beat MichaelAZ's bike up Olds, and I also beat GregV at one of other hills in Glamis. It all comes down to tuning.

AZRaptor

 

we went to the oregon dunes a few weeks ago and my one friend has a stock bore raptor with piston and a hot cam what level i don't really know but it really runs well. then one of his raptor friends comes out with his newly done 770 raptor (well broke in new) so we all head off to comp hill, we were all excited to see what the 770 would do, well the excitement was short lived, bob put about 5-8 bike lengths on him and that isn't much of a hill. to make things worse the guy raced my wife on her ds and lost. we were all kind of in shock, the guy put like $2800 in the engine and another $900 in some carb set-up. well maybe this was the worst set up quad ever and can be dailed in, but we all left shaking our heads, except bob he almost bought that kit, i thinjk he was smiling as we left that day.

 

Sounds like another Dirtwheels story if you ask me.

 

Sounds like maybe a bad setup, or not tuned well :-/

 

Ben on Gregs and Mikes behalf they were both tall geared and jetted wrong but taking nothing from you ,,you had a very fast bike
Right now as we speak I'm building your set up with my own porting and a few other tricks...[img]i/expressions/face-icon-small-smile.gif[/img]

Pat

 

Whats considered tall gearing, just curious.

 

I think they were both running 14 or 15 /40 and later after we all went to china wall together Greg went down to just stock and it helped him alot

 

AzRaptor,
From the dyno runs, it looks like you have a 12:1 piston and a cam, what else was done to your Raptor? And it was all done by Craycraft right?

Thanks,