[jsander9]

I just picked up a real clean stock crf50, starts right up. When I'm riding it and give it full throttle it breaks up and won't fully run out into high rpms....any suggestions?

 

[LongMooie]

#1 clean out the stock air box/filter and pull the carb apart and fully clean it out
#2 check the valve lash
#3 check the electrical connections

 

[jsander9]

Valve lash?? Sorry Im not sure what that is? Just the valve adjustment??

 

[mxmen]

#1 clean out the stock air box/filter and pull the carb apart and fully clean it out
#2 check the valve lash
#3 check the electrical connections

+1 on cleaning your stock air filter or just put a UNI foam filter on that lil stocker!

 

[tmas]

Valve lash?? Sorry Im not sure what that is? Just the valve adjustment??

Yes,............. and throw a new spark plug in it.
tmas

 

[manforrilla]

And pull the carb apart and blow out everything. You can carefully pull each of the screws with springs and such out and blast them with air from a compressor and gas will go everywhere but if there is dirt in there it will totally act like that.

 

[eIghT-siX]

make sure the ground bolt is tight. i forgot to tighten one and messed with the jetting forever before i figured it out.

 

[jsander9]

Ok so here is an update......cleaned carb, cleaned air filter, tightened ground bolt, all wires are tight. The only electrical that was removed was the kill switch. Valves were measured and seemed to be set appropriatley.( drug just a little bit on the feeler guage at .0025) Now what?????

 

[jsander9]

Oh and put a new spark plug in.

 

[jsander9]

Help!

 

[eichkay]

got a pic of the setup.. make sure the stock carbi is the stock carbi and not something bigger .. you just never know sometimes

 

[eIghT-siX]

stock throttle housing? they have a limiter. bad gas? did you look thru the main jet when you cleaned the carb? ive had a flake of sand stuck sideways in one before. acted kinda like a butterfly valve. could hardly see it.

 

[LongMooie]

If you have another bike you can swap parts out one at a time to locate the issue if there is a bad part
CDI box
coil
stator

the only other mechanical thing you could check is the cam timing
and i know this might sound silly but dump the fuel and put some fresh fuel in the tank