[rivera82]

ok, so i took muy R out past saturday and after riding a bit i ran out of fuel, pushed it home and poured close to 2 gallons after riding for about 1 1/2 hrs i ran out of fuel, what can be the cause for that much fuel consumption? or is it normal for the R? my main jet is a 152, my needle is a d177 and slow jet is 40, looks to my like Im lean all around but it runs good, except it does not iddle, so were is my fuel going?

I checked my top end and it looks like its time for a rebuild (some scaring on piston), but will needing a top end and low compression (145psi) cause it to burn exessive fuel, not too long ago my son and i rode around 6 hr on a full tank, him on a Blaster and me on a YZ250.

 

[mx250r91]

The float shut off level in the carb could be a little high and cause you to lose a lot of fuel out of the carb vents if you ride over rough terrain. I lowered the fuel level on a brand new 38 PWK AS as I notoced I was going through a lot of fuel which seemed to be coming out of the bents and now only use about 1-1.5 gallons over a 90 minute woods race with a 185 main.

 

[justtwistit]

are u easy on the throttle? that is the leading cause of fuel usage hahahaha

 

[rivera82]

ill try the float, hope it takes care of it, as far as riding, i haul ass never easy on the throttle, hahaha

 

[acecarlos]

Worn Rings or bore or low compression will consume more fuel. Actually, the Fuel is un-burnt and expelled out the exhaust. Time for a Top End rebuild...

Carlos

 

[rivera82]

well i found out the issue to my bad compression, i went from 140 psi to 190 psi with a new top end, but I'm still smoking like a chimney and going thru fuel like there's no tomorrow, 2 gallons in 1 1/2 hrs, my slow jet is a 50, it wont idle and the smoke is thick and lingers, compared to my blaster and YZ250 its like 3 times as much, could it be that i need to be really lean im thinking of somewere in the 40 vicinity on the slow jet, what do you guys think?

PS

The top ring broke in 3 parts, i only managed to find 2 could it be that the 3rd one left thru the exhaust?

 

[audioworks04]

Do a plug chop and base you jetting off of that. No one can forsure tell you what you jetting needs to me just by reading your post, especially without a list of mods.

 

[rivera82]

Sorry about that.

Paul Turner Pipe
Boyesen Reeds (no markings)

Ported and polished cylinder bought from forum member bore out to 67.25mm

Checked compression and got 190 PSI.
My slow jet is a 50
Main is 152
and needle is in the third clip.
According to suggestions from Carlos 48-50 Pilot, 155-170 Main, DGH needle 3 rd Clip from Top, 1 3/4 turns out on the AS...turn Choke Knob CCW to raise idle, use cable adjustment as well.

So if he suggested a 155-170 main and I'm running 152 , then my slow would be something like a 40 or 42 no??

 

[motofool250r]

did you check your float height is it set properly?

is your pipe absolutely coated with black wet oil? (inside and silencer packing?)

what elevation/ location are you riding in?

 

[rivera82]

did you check your float height is it set properly?

is your pipe absolutely coated with black wet oil? (inside and silencer packing?)

what elevation/ location are you riding in?

Float height at 16mm
Have not checked the pipe
elevation 3800 feet (1140 m) El Paso TX


Paul Turner Pipe
Boyesen Reeds (no markings)

Ported and polished cylinder bought from forum member bore out to 67.25mm

Checked compression and got 190 PSI.
My slow jet is a 50
Main is 152
and needle is in the third clip.
According to suggestions from Carlos 48-50 Pilot, 155-170 Main, DGH needle 3 rd Clip from Top, 1 3/4 turns out on the AS...turn Choke Knob CCW to raise idle, use cable adjustment as well.

So if he suggested a 155-170 main and I'm running 152 , then my slow would be something like a 40 or 42 no??

 

[motofool250r]

you could easily drop a pilot jet it seems, what i wonder is if your crank seals are good if that burning is not crankcase oil and not 2 stroke oil.

any leak down test performed?

which brand of oil and what mix are you running?

 

[rivera82]

No leak down test,
Lucas 2 stroke oil

Ill have to do the leak down test, to be sure, but I'm still going thru a lot of fuel.

 

[motofool250r]

ever see any pour out the overflow hoses?

 

[atvmxr]

) El Paso TX

Howdy neighbor! Another R rider from TX on here, cool. welcome aboard

 

[rivera82]

ever see any pour out the overflow hoses?

no, I did see a little but i think it could have been from jumping or something cause i usually see it from my dirt bike too

 

[rivera82]

Howdy neighbor! Another R rider from TX on here, cool. welcome aboard

hey partner, hahaha, guess what i ran it with a 40 jet and it idles!! but im really lean no??

40 slow jet
152 main
d177 needle, what is that?
almost 2 turns out, on the air screw
but it idles!!

 

[motofool250r]

40's probably too low my friend, i tried to search quickly for the needle you have it seems its an oem needle from something you'll have to convert it over with the charts

 

[rivera82]

What do i do?? how can i verify that it is correctly jetted on the slow jet?

 

[efi2stroke]

pilot or slow jet is determine by air screw 1-1/2 to 2 full turn after you close off, 2 turns is too.far
change pilot jet by if out more than 2 turn go down smaller number 52 to 50,if if idle with the air screw under 1 full turn go up
IF PWK chock system is not part or idle circuit,it is on PJ that why pwk is a much better carb .

 

[rivera82]

pilot or slow jet is determine by air screw 1-1/2 to 2 full turn after you close off, 2 turns is too.far
change pilot jet by if out more than 2 turn go down smaller number 52 to 50,if if idle with the air screw under 1 full turn go up
IF PWK chock system is not part or idle circuit,it is on PJ that why pwk is a much better carb .

My air screw is almost 2 turns out, what could be a cause to run so lean on a new top end, an air leak would cause me to run a richer jet no?
40 slow jet
152 main
d177 needle, what is that?
almost 2 turns out, on the air screw
but it idles!!