I have 351 with 33-34 pumper. I'm jetted for 6000' so not much help except to say to contact bill as he helped me getting my bike dialed in. I would contact him. If you can't lift front wheel with throttle, something is up. If I ride conservatively I can get about 50 mpg but usually closer to 40. I have Kdx snorkel and q4. About 3500 miles so far and no problems! Really enjoy bike as a 351!

 

I have a 351 with 34.
You didn't say your elevation.
Did you tune the carb with the kuba screw?
I had to rejet mine. Your mileage has just went south, you don't get more power for nothing.

 

I'm at sealevel. I've not done anything with the carb, apart from adjust the idle screw.

The idle is even a little erratic as in it'll happily idle along at 2000, then after a few secs drop to say 1500, like when im waiting at a set of lights, then i'll give the throttle a blip in neutral, and it'll go back to idiling at 2000.

I've done nothing in terms of trying to dial it in myself, as i'll probably only make it worse than what it is.

I'll be giving Bill a call today, as by the time i get home tonight, i'll be past the 100miles and able to give it an oil change and give it full throttle.

 

If you didn't tune the carb on the bike, running... that is probably your problem.

 

Gave it some full throttle from standstill for the first time, as i'm at 100miles (despite being on the breakin oil, i thought it'll survive !!!) and the thing chugged all over the range.. Seems to run better with only half throttle.

I hope the pumper doesn't prove to be too much of a pain getting everything dialed in. I still have the CVK on stock jetting at home that i could put back, but even that will need some new jetting, as that was jetted for the 250 cylinder.

I'll admit, i'm not all that confident on my ability to jet a bike correctly.. Its one of those things that if its working, then i'm not touching it.

Want to see that front wheel come up in 1st, then i'll be a happy camper.

 

Hey Doc, just wondering, what 351 kit number did you get?

 

I think it said # 608. Didn't pay too much attention TBH.

 

Spoke to Bill

He said, take the lid off the airbox, if it runs better get a leaner jet

If it runs worse get a larger jet.

He seems to think he put a 142.5 main jet in there. Not 100% on that though.. He also said my gas mileage is low could be one of two things.

1.\ i have been blipping the throttle a lot more than usual because i've been running her in, and wanting to not keep the bike at any one rpm.

2.\ i'm running very rich.

I'll take the plug out tonight and see if she's all sooty, and try taking out the airbox lid to see if there's any improvement.

 

Simplicity in diagnostics!

 

First thing you need to do is adj the air/fuel jet, come on, it takes 2 minutes.