Gas mileage

I have a xj650 81', stage 3 dynojet kit, #142 main jet, pod filters, averaging 100 miles to the tank, good ro bad??

 

100 / 2.8 gal = 36 MPG

Not so good - you should be shooting for 46 MPG of traffic-speed hi-way cruising.

What do your plugs look like ??

 

Yeah if im on the highway its horrible, let me check and i will get back with you.

 

My maxim x is going into the shop this weekend.... (A buddy owns a vintage motorcycle shop and does my work dirt cheap) I wish I was getting 100 to the tank.... I've been having reserve come on around 70 miles and am filling up around 85-90 if I push it

 

8O

http://www.xjbikes.com/Forums/viewtopic/t=38967.html

Just found your thread in the link above. You've put up with the bad fuel consumption for this long?? I hope by now you've at least checked the valve clearances

 

Just did a mileage check on the Seca yesterday. 57 miles at 4500rpm was 1.1 gallons for 51.8 mpg Best I've gotten so far.

Worst was last year when mixture screws were off a little - 39.2 mpg

Colortune and a proper sync, with all parts in good condition, should get you at least 45 mpg

 

I have no clue what my mileage is!! Have never even checked. I just get on and fill up when I need to.

 

Unfortunately not yet. That's all getting done this weekend. I switched jobs so things were a little tight for a few weeks. But all good now. Getting a fork rebuild and upgraded springs, carbs re jetted, exhaust mounted better, led turn signals and fog lights added, valves done, brakes front and rear and lines. Should be like new when I am done! Also may do the tank "Bondo/paint" while we're at it.

 

I wish this was more popular of a topic -
470 MPG at 60 MPH on real roads.

http://craigvetter.com/pages/470MPG/470MPG%20Main.html

But none of that XJ acceleration. Just a 125 and some streamlining.

 

My '83 XJ650 was getting in the 30's which seemed pretty bad to me until I replaced the intake boot gaskets and clean the bottom ends of the carbs, then it went to a consistent 45+ with 55 mpg predictably when ridden at 45-55 mph with few stops...

It was all stock though.

If you were getting 100 miles before going to reserve, that'd be in the same neighborhood...otherwise, not so good....but not unexpected with that kinda setup.

 

i average 50ish with my 650

 

470!!! No SH*T
jk.
i average around 45.

 

bTW has anyone seen the new Royal Enfield Classic 500 with F.I. now?

They claim 80+ mpg....nice lookin' bike too...wish they didn't have such a lousy rep for breakdowns...

 

I nearly got 52 one time, on a perfectly straight stretch of ideal road cruised consistently for 90 miles at 60 mph. Bike was running lean though. That was the '82 650.

This one, an '81, no carb srvice to speak of for the last 4 years, got 38mpg highway with a huge load on the rear rack, that, aside from being heavy, is also definitely not aerodynamic. Aside from that, I also wasn't staying in the happy-zone for mpg; that was me riding 75mph+.

I noticed 33 around town, though, which is much worse--though it's worth noting that I ride rather aggressively, and relatively frequently take 1st gear to 9.5k for the shift.

But yeah, 47 is the number to shoot for. Fitz standard of quality care and service will see you hit 50. (Only really counts if you have tan plugs, though!)