250-500cc Fuel consumption during slow riding

[boomhauwer]

Hi all,

I have a question which I didn't found an answer for.

When I'm off-roading in the woods, the average speed is not very high, to my surprise the fuel consumption is.
I'm talking about 8L / 50KM (roughly 2 gallons/30 miles). When I'm on the road, the consumption also sky rockets when i'm in slow traffic. It actually has a better mileage when driving hard all the time then driving slow.

I've checked my spark plug and it's fine and fitted a new one to be sure, same result. The air filter is clean and new.

Carb setting is (pwk airstriker JD kit):
needle 3rd position
main jet #170
Pilot jet #42

Is this normal or does my carb spit any excess fuel out through the breather lines?

thanks

 

[Husqvarnabrett]

Check you float level hieght, it should be 16mm from the upper float bowl mating surface to the bottom of the float.. Also before you do that check you float needle and make sure there's no grooves or anything worn into the rubber tip, it should be a perfect taper with no flaws

 

[justintendo]

i ran my 88 250 67 miles the other weekend and used about 4 gallons. that was a mix of 40% tight woods, 40% tight/medium trails, 20% wide open fields. a good chunk was running the bike with a lil anger and the rest was stuck behind utv or getting into gnarlier stuff in the woods. i thought that was pretty good for me being 230 suited up and a older mikuni vm carb. the 88 is tuned very well also. it would have definitely been worse taking a bigger bore bike altho my 360 has been helped greatly so far with the lectron in regards to fuel usage.
mileage is hard to analyze i think without really seeing how someone operates their machine. im willing to bet i could cut my fuel usuage down quite a bit and carry somewhat similiar or slightly slower times. i wasnt too far from my fuel can so i rode with reckless abandon in regards to using fuel.

 

[2premo]

running at high RPM is not as aggressive as constantly accelerating
the needle is set to leave the fuel ratio a bit on the rich side when the slide lifts to compensate and prevent a lean out condition
so a lot of small consistent throttle movements use more fuel than holding higher RPM

 

[shrubitup]

check float height. That's fairly high consumption (15 mpg). Tilt bike to left and right with gas on. If it drips fuel before 45* then the float is too high.

 

[boomhauwer]

check float height. That's fairly high consumption (15 mpg). Tilt bike to left and right with gas on. If it drips fuel before 45* then the float is too high.

Good tip, I will check this!

 

[2premo]

Hi all,

I have a question which I didn't found an answer for.

When I'm off-roading in the woods, the average speed is not very high, to my surprise the fuel consumption is.
I'm talking about 8L / 50KM (roughly 2 gallons/30 miles). When I'm on the road, the consumption also sky rockets when i'm in slow traffic. It actually has a better mileage when driving hard all the time then driving slow.

I've checked my spark plug and it's fine and fitted a new one to be sure, same result. The air filter is clean and new.

Carb setting is (pwk airstriker JD kit):
needle 3rd position
main jet #170
Pilot jet #42

Is this normal or does my carb spit any excess fuel out through the breather lines?

thanks

as they said check the floats, but that is not off of my mileage
when i ride in the trees there are also climbs to deal with
i don't know the terrain you ride on but when i am only in the trees thats about right
now if you mix itup a little some straight riding you should expect 25% better but don't be surprised if it uses a lot of fuel offload

 

[ajaxauto]

I get about 20 MPG on my 125, 165, Wr 250 and my CR 300 That is Racing National H&H Does not matter if it is wide open desert or tight in the trees aways about 20 mpg