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secondfield
6th October 2008, 22:29
Since Ive had a new piston put in the rmz (JE 12:8) shes, chewing through alot of gas. Its running a bit richer (not so rich as to inhibit starting).The plug doesn't foul completely, but looks blacker than norm, even with the fuel screw wound up to its max (leanest position). Where a couple of the boys riding 450's use about 5 liters for a loop, im using about 7!

Any suggestions? Its not leaking away either....

CRF119
8th October 2008, 13:04
There is no way that using that much more fuel is cause by jetting. Not in my experiance anyway the bike just wouldnt run if it was that rich.

The fuel mixture you are playing with is the zero to 1/4 throttle screw right??

secondfield
8th October 2008, 19:28
Yeah mate, I know that sounds kinda odd .. ive checked for leaks but there are none.... The fuel screw is up the front end of the carb .. the same deal as an air screw on a two stroke, but in reverse..

I think your right about the fuel screw regulating the fuel mix from the pilot jet up to about 1/4.

Being a snotty terrain rider, I hang around there a fair bit in that position, but will drop the needle another clip as am also on 3/4 throttle alot between the tight stuff ..

Its got me stumped ..

cheese
8th October 2008, 19:58
Sticky float???????

dammad1
8th October 2008, 20:46
Sticky float???????

And check the float level as they often can be a little on the high side.

Reckless
8th October 2008, 22:48
yes good place to start it might be ok on the flat but pissing out fuel though the overflows when you are riding. How far can you you lean it over before you see it coming out. Also check the float needle is seating/sealing properly.