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bone705
10-04-2003, 11:08 PM
My friend has a 97 300ex. he was riding it around the yard the other day and it suddnely lost a bunch of power. It will idle fine but when u get into fairly high rpms it just falls and acts like its going to die then it picks back up again. we have tried different cdi, coil, stator, check flywheel key, checked for leaking head gasket, took the head cover and all the vavle springs and **** look good. The motor has a failry new hi-comp piston, web cam, hardend rockers, and heavy duty valve springs. any idea what our problem is?
hondafox440
10-04-2003, 11:16 PM
Check the compression on it, and do a leak down test to see if there is an air leak anywhere.
danney f
10-05-2003, 12:59 PM
Check the carb, could be it's not getting enough fuel. clean the screen in the pet-cock on the bottom of the tank.
Bill Fuller
10-05-2003, 01:05 PM
Sounds like a carb problem to me.
honda250xrider
10-05-2003, 01:49 PM
what jetting do you have on your carberatur
Out_Sider
10-05-2003, 03:33 PM
definatly a carb problem...check the jets, and clean the whole carb, and i would use about a 130 main jet and about a 40 pilot in it, with the mods u listed...(there is an exhaust right...)
bone705
10-05-2003, 10:02 PM
i dont think its in the carb becasue we took my carb off mine which works fine and it still ran like crap. he has about the same mods as me so the jetting should of been real close.
danney f
10-06-2003, 01:13 AM
Have you checked the air ways? makeing sure that nothing keeping it from getting air. It also sound like what mine does if I forget that I have the choke on and I try to gun it. Check the airfilter, clean it if need be. make sure there is nothing in the tube. try running it with out the filter. IT IS ALWAYS QUESS WORK, UNTIL YOU SOLVE THE PROBLEM.:confused:
jason4282002
05-17-2005, 09:53 AM
take the spark plug out and stick your finger over the whole and turn the engine over and see if it will blow your finger off the whole. if you can hold your finger over the whole without any air excaping it is probably your compresssion. if so what i did was spray some wd-40 in there and let it sit for a min... and blew it back out by turning the engine over and it worked fine.
Bill Fuller
05-17-2005, 11:33 AM
After almost two years I hope he got it fixed by now:devil:
Trevor
05-17-2005, 11:52 AM
sOUNDS LIKE A FUEL PROBLEM check the fuel filter on the bottom of the tank