Personally I think you need 760+ and big RPM before going to dual 39mm carbs. Thats my opinion based on some dyno sessions I've been involved with.



MrHorsepower

 

I have the dual 39's on a stock bore motor, I think it was one of the best mods I did. Unbelievable power and rev. I gained about 3 bikes on AZ's med bike when I went to duals and he was on 48 lectron alky.

I've never really ran against any other fast DS's though, guess we'll find out at DS Days.

 

Majorecho,

awesome link on porting.

jbt

 

i'm running the 45 on my 720 with race head, i think that engine mod made the 45 work much better, the guy with the 760 duals and i talked about this a little and the duals, are the way to go for all out performance, the difference was slim, and the ability to ride easy went to the 45 just what another rider thought. plus that was in light fluffy sand, f it got sticky the duals might pull out a bigger lead.

 

I think the duals really shine on the big hills- on the flats they do some good but hills are where it's at!

 

does anyone have dyno runs showing the difference with the duals over single carbs?