re jeting

[barker]

ive put a 150 barrel and piston on my 125goes ok untill its given full throtle when this miss fire accures changed the plug so its not that

wonder if its starved of petrol at full throtle should i up the jet and if so to what, a 125 runs a 95 main jet

[barker]

missed the inpotant bit bike is a honda xr125

[megawatt]

Put the jets or carb on that a 150 uses?

[barker]

they don't make a xr150

[megawatt]

Find out what size jets a similar 150cc bike to yours takes, or it's gonna be trial and error. Or get it on a dyno to find out the air/fuel ratio. Maybe a tuner of similar sized bikes will know if you give him the work.

Probably cheaper to just keep going up in jet sizes until it runs rich, then backing off a size.

[barker]

trouble is there are not many 150cc bikes in the uk any more will have to see what i can find out from honda

[rider555]

trouble is there are not many 150cc bikes in the uk any more will have to see what i can find out from honda

 

I had same problem on my lexmoto 125 when at full throttle misfired few times original jet was odd size 94.5, replaced with 100 jet and all good, with your 150cc I would say start at 100/105 and run it see if works, you will need to even go higher if other changes has been made like free flowing exhaust or air filter, you will find this will be more of trail and error, also make sure your air filter is nice and clean.