[zacblank]

Hello everybody i am new to the forums and was looking for some guidence on a 2003 zx 636 i picked up the other day. I bought the bike very cheap knowing it had issues but trying to fix it for a stunt bike so i can quit wrecking my street/track bike. Here we go though can get the bike to start and run but, the only way to start it is to hold it full throttle and to keep it running no less than half throttle. Also along with this issue the bike will not exceed 1500 rpms like it is hitting the limiter so im assuming these problems are connected. Just figured i would post up to see if other people have had similar issues and their thoughts on it. Appreciate any and all feedback i can get.

Thanks, Zac

 

[zacblank]

Oh have already been through the service manual as well and tryed to get codes but no luck with that!!!

 

[zxrider432]

change your plugs... if not that check the coils.

 

[zacblank]

Already did the plugs still need to check the coils though. How would i go about checking to ensure they are working correctly. Im not real big on this mechanic crap this is why people have pit crews haha.

 

[IcantRideforShit]

is it running on all four cylinders? any back firing or missing?

 

[r3vlimited]

I'm not a professional motorcycle tech, but it sounds like your not getting enough fuel. More throttle equals more fuel right? So when you let off the throttle your not getting enough fuel now, and your bike shuts off. So maybe a fuel line is jammed up, maybe your fuel injectors are jammed up, maybe fuel rail is jammed up, maybe your throttle cable isn't even opening the throttle body's all the way. Maybe your fuel pump cant even keep your fuel system primed. Now you can also not be getting enough air, maybe your air filter is jammed up. Just hope its not a electrical problem.

 

[zxrider432]

snap on or mac make a ignition tester. it kinda looks like a pen, that will test to see if there is power flowing, or there is a spark tester that snap on makes. it looks like a stubby screwdriver but with a coil wire coming off one side and the other side looks like the top of a sparkplug.

 

[zacblank]

Its dumping plenty of fuel i got all of that checked out today but i beleive we have an electrical issue. Today i had the tank lifted and had it running and found out that the butterfly valves on top of my motor are not opening. There are two sets of valves the top set is run electronically and the bottom set is what is controlled by the throttle. My top ones are not openeing when i flip the key on they open then close like they should but when the bikee is running and im giving it throttle they are not opening along with me giving it more gas.

 

[zxrider432]

if im not mistaken they aren't supposed to move unless you have the whole bike together and your riding it but i could be mistaken. you can remove those plates attached and then try it

 

[christikitty]

I would remove the low speed throttle plates connected to the servo. Or jsut disconnect the electrical and manually move the butterflies open. See what that does.

 

[zacblank]

Yeah i could open them manually and it would rev higher but stilll wasnt right at all. Im thinking im just going to buy a new servo for that and run a new wiring harness even though i was trying to avoid that but you can pick up a harness on ebay for like 60 bucks.

 

[zacblank]

I believe the bike was tore down and rebuilt by the previous owner so is it possible that the throttle position sensor got messed up or incorrectly installed. just wondering if anybody has fooled with one because i have not!!

 

[zxrider432]

i just removed the plates, the tps still works but cant control anything with out plates, what mods are done to the bike, how many miles...some more info might help