FCR Jetting on a 680R

After dealing with my Edelbrock on my 680R custom ATV project I am switching to an FCR off an 02 CRF450R. My plan is to have it smooth bored to 43.5mm and billet slide from DASA racing. What I am going to need are some ballpark jetting figures for this setup, or at least a starting point.

I am in Oregon and ride mostly near sea level often at the beach/dunes so lots of moist air but I also spend a couple weeks at 5100' elevation in Eastern Idaho every year as well as the occasional trip to Glamis in SE SoCal. Motor is running a K&N air filter and Big Gun Header and can.

The Edelbrock works OK, but I keep having to mess with it, this trip it was a sticking fuel delivery valve. Its not a fun feeling to be shooting a huge bowl in 5th gear and have the bike run out of gas all because the valve sticks. The throttle pull is extremely heavy also so I am looking to make that easier as well for those 50 mile rides... Oh, and yes, It was just sent in to Edelbrock to be refurbished at the end of the last riding season so its not like it is "old".

Anyway, if someone who has a FCR on a 680R (or even a 650) can give me some ballpark settings on the jetting, air screw settings that would be very much appreciated..

sounds like a good ? for eddie s. in the jetting forum!

sounds like a good ? for eddie s. in the jetting forum!

Aha, good point.. I'll cross post over there and see if he can help...


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