# runnin on one cylinder



## brutelaws29.5 (Apr 10, 2011)

a buddy brought me his brute its and 08 efi. ive confermed its only runnin on the front cylinder. i tryed isolating the rear cyinder by unpluggin the front injector to make sure its not jus insufficent fuel pressure but no change. the bike was jus rebuilt by someone else my question is could this be cam timing??? BUT the kicker is i have 60psi compresion on both cylinders......... any thing else to check before i get deep into this thing ps. fuel is 4 oz per 3 seconds thanks in advance


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## filthyredneck (Feb 10, 2010)

Check the rear spark plug for fire, could be a bad plug, plug wire, or coil. I just replaced my front coil a few weeks ago on my 08....one of the prongs was badly corroded and about to break off the front of the coil and it was running terrible.

"Killing Time Using Tapatalk 2"


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## brutelaws29.5 (Apr 10, 2011)

thanks i already swapped plugs and coil with the working cylinder and no change......


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## hp488 (Sep 23, 2009)

brutelaws29.5 said:


> a buddy brought me his brute its and 08 efi. ive confermed its only runnin on the front cylinder. i tryed isolating the rear cyinder by unpluggin the front injector to make sure its not jus insufficent fuel pressure but no change. the bike was jus rebuilt by someone else my question is could this be cam timing??? BUT the kicker is i have 60psi compresion on both cylinders......... any thing else to check before i get deep into this thing ps. fuel is 4 oz per 3 seconds thanks in advance


"If you un plugged the front injector and there was no change" are you sure it is the front cylinder that is working?


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## rmax (Nov 21, 2009)

i had 1 like this awhile back, the cams 1 of the cams was out 90 deg, must have turned the crank the wrong direction when they had pit it back together, i actually did this on mine the first time i replaced the chains, but caught it before trying to crank, realize i had had a brain fart, an went in for a second look, then i got the other machine (2nd hand) tryed everything, finally checked cam timming, corrected an went smooth from there, the flywheel on the infected bikes trigger the injectors, so the fire an fuel sequence are off ,not letting it combust i think its fireing the cylinder on the exhaust stroke


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## DaveMK1 (Nov 8, 2009)

Try flipping around the injectors. Take the front injector and switch it to the back cylinder and vice versa, then see if the problem follows the cylinder or the injector. Dont know if that can be done easily on these bikes seeing how mine is carb'd.


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## brute for mud (Jul 15, 2010)

brutelaws29.5 said:


> a buddy brought me his brute its and 08 efi. ive confermed its only runnin on the front cylinder. i tryed isolating the rear cyinder by unpluggin the front injector to make sure its not jus insufficent fuel pressure but no change. the bike was jus rebuilt by someone else my question is could this be cam timing??? BUT the kicker is i have 60psi compresion on both cylinders......... any thing else to check before i get deep into this thing ps. fuel is 4 oz per 3 seconds thanks in advance


did you check for spark on the dead cylinder ?


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## brutelaws29.5 (Apr 10, 2011)

Yes I checked spark on dead cylinder it has good spark and when I unplugged the #1 cylinder it wouldn't run at all I am thinkin the same as you rmax I bet the #2 can is in out of time the thing that threw me off is I have good compression and the only explanation would be if its 90* out of time I'm gone on work for awhile so when I get back in and get back on it I'll let you guys know how things turn out thanks for all the help


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