Hey guys so i bought a used bike recently apparently it had a top end rebuild rode fine but every time i go riding it loses power or turns off / missfires and everytime i check the spark plug it seems to be fouled . It's got stock jetting everything stock except for a pro circuit silencer . The spark plugs seems to always look : Liquidy black or dry black . Its got an exhaust leak near the header i bought the gasket i'm awaiting for it to be received could this affect the richness? I run 33:1 with shell oil do i need to change the jetting ? If yes could anyone help me through it i'd greatly appreciate any help guys the bike has been driving me crazy . Spark plug that i use is a B8HS
2 Stroke CR 125 01 Fouling spark plugs
- Thread starter madguru100
- Start date
Hi mihylo could you possibly wale me through the steps of setting the float height or is there a video? Thanks mateStart by cleaning the carb twice and then cleaning it for the third time just in case you missed something. Then set that float hieght. After hat let us know how it runs and then we can go from there.
Checked floats and cleaned the carb all seems to be fine the Main jet is 172 and Pilot jet is 58 what sizes do you think i should drop down to? Thanks .Start by cleaning the carb twice and then cleaning it for the third time just in case you missed something. Then set that float hieght. After hat let us know how it runs and then we can go from there.
Every bike jets differently and there are so many variables it isn't funny. What's your ASL? Are you running pump gas or race gas? How fresh is the top end, is the powervalve clean?
It's a 125 so are you lugging the motor or are you letting it rev at 10,000 rpm like it was designed for? Also doesn't that bike get a B9 plug?
I'm running my country's pump gas . Top end apparently only has 1 hour on it . If got no idea if the power valve is clean most probably it is since i bought this from an ex racer . I'm not always on full throttle but i wouldn't say that i ride slow i try not to let it idle i pull the clutch in and always give it a quick throttle even when i'm going slower around tight corners . Yes its true the bike does get a b9 plug but i think the ex owner did a colder plug for it to not foul easily even though he used to be always on the gas . He said he never touched the jetting so everything is stock and i heard hondas come out rich from the factory .
you mention that you "checked" the floats, tell me how and what you set them to please?
the b8 plug is HOTTER, not colder than a B9. your former owner and racer was bandaiding what you might guess i am thinking is a leaky or improperly set float.
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that sounds very much like the setting (it is the exact setting in fact) for a keihin pwk carburetor. also for the keihin pj. as i recall the 2001's that came to this country were mikuni but i co uld be mistaken. you may want to verify that. next, how did you determine it was really shutting off at that point ?
https://www.youtube.com/watch?v=aiexehn33kg . i used a few tools to get to make sure everything was right . My one is definetly a keihin . I might recheck the floats cause you're making me doubt that i did it right now .
If got no idea what size it is . The big circular side not the one next to the choke is 6 cm . Maybe it's a 38mm? no idea i think its an upgrade
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If got the cr 125 2001 manual and jetting specs are : https://gyazo.com/16f400ba40a21a392a61341aaac2e0a3 but i'm not sure if this is for the kehin carb any ideas for that model where they from stock mikuni or keihin ? Cause if they were keihin my carb is way out of wack