yz 125 problem

if you dont have enough clearance there, minimum of .75mm i would be nervous about piston damage. you need calipers to set the float or a rule graduated in small amounts. a way to set it to acceptable withough knowing the factory suggested is to take the carb off, turn it upside down on a flat surface and make sure that the floats are both perfectly level and even with eachother. set that tab that contacts the float needle to where the arms of the float and the float needle are at a perfect 90 degree angle when the tab is contacting that spring loaded tip in it's fully extended position. this is done after you clean out the float needle socket and seat and make sure the needle's viton tip is in good shape. kind of a lot to think about but if you take it apart and read it while you are looking at the parts it becomes clearer. the float will have the greatest mechanical advantage for shutoff at that 90 degree angle and then on in the direction of movement. once you have that set, measure the distance to the float tops (top as it is upside down anyway) write the number in the notebook you are keeping on this bike, and refer to it to reset until or unless you you get the factory setting. from there you can jet for that specific float setting. if you really want to see that the float is shutting off fuel at that point, take a long enough piece of fuel like that you can blow lightly through it while looking at the carb at eye level. move the float with your finger and see where the air is shutoff or greatly impeded.
 
if you dont have enough clearance there, minimum of .75mm i would be nervous about piston damage. you need calipers to set the float or a rule graduated in small amounts. a way to set it to acceptable withough knowing the factory suggested is to take the carb off, turn it upside down on a flat surface and make sure that the floats are both perfectly level and even with eachother. set that tab that contacts the float needle to where the arms of the float and the float needle are at a perfect 90 degree angle when the tab is contacting that spring loaded tip in it's fully extended position. this is done after you clean out the float needle socket and seat and make sure the needle's viton tip is in good shape. kind of a lot to think about but if you take it apart and read it while you are looking at the parts it becomes clearer. the float will have the greatest mechanical advantage for shutoff at that 90 degree angle and then on in the direction of movement. once you have that set, measure the distance to the float tops (top as it is upside down anyway) write the number in the notebook you are keeping on this bike, and refer to it to reset until or unless you you get the factory setting. from there you can jet for that specific float setting. if you really want to see that the float is shutting off fuel at that point, take a long enough piece of fuel like that you can blow lightly through it while looking at the carb at eye level. move the float with your finger and see where the air is shutoff or greatly impeded.
cheers mate! after fidling abit qith the carb its being a bitch to start now think ive lowered the float too much now! trying to get the float set right with the needle and moxture screwnis a right pain! never had a problem like thisnwith a carb lol
 
Does that mean you have primed the source and had your premix lapped?
plug has been coming out wet and its been struggling to start the past few days so had a good look today and realised the o-ring headgasket had stretched massively causing a blow so coolant has been leaking in may have been the reason all along! wasnt a massive leak just enough leaking for it to be a bitch! thats a brand new headgasket though the second one in a few weeks so either my head needs skimming or theres too much compression right??
 
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