Bike running on only 3 cyclinders

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titch zxr
Posts: 11
Joined: Tue Feb 23, 2010 3:01 pm
My Bike: zxr400

Bike running on only 3 cyclinders

Post by titch zxr »

Hi ive been out on my bike twice now and after riding about 15 minutes it starts to fire on only 3 cyclinders.Its doing my head in much help be apprecitated.Thanks
MillaMeter
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Re: Bike running on only 3 cyclinders

Post by MillaMeter »

titch zxr wrote:Hi ive been out on my bike twice now and after riding about 15 minutes it starts to fire on only 3 cyclinders.Its doing my head in much help be apprecitated.Thanks
Hi,

Welcome to the forum for a start :smt006

This issue could be a number of things. Have you tried trouble shooting the bike yet? Try changing the most simplest things like the spark plugs? Changing ignition coils, spark plugs caps, and ignition leads. If all else fails, check the carbs over make sure everything is where it should and nothing is blocked.

Still failing to fire on all 4 then could be the worst case of bad compression, valves not seating correctly or even the CDI Unit (ECU) breaking down. Mine did this once, I only had 2 cylinders working and took me almost 2 weeks to pin point it down to a fecked ECU.

Regards

Rich
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titch zxr
Posts: 11
Joined: Tue Feb 23, 2010 3:01 pm
My Bike: zxr400

Re: Bike running on only 3 cyclinders

Post by titch zxr »

Thats brillant mate check that and will get back to you.Cheers Titch
JimmyB
Posts: 2
Joined: Fri Aug 03, 2007 4:35 pm

Re: Bike running on only 3 cyclinders

Post by JimmyB »

I have the same problem even though I'm not sure it is actually running on only 3 cylinders. When i pull the plug cap out of #4 it still seems to make a minor difference in how the bike is idling. Anyway, I was wondering about something else I noticed: When the bike is idling and i place my ear on the carbs' air intake i can hear and feel it sucking air in. The suction however is getting gradually less while moving along the carbs, ie. cylinder #1 seems strong/ok, cyl #2 still ok but not as strong, #3 somewhat flowing (can hear the air going in but not feel it) and finally cylinder #4 where nothing really moves until i blip the throttle. I take it this due to an air leak and the rubber inlets are to blame. Could it have something to do with the carbs as well? I had them cleaned last year and rode the bike for maybe a month until it started to give me trouble. It would start and work fine until i got home and as time passed, the problem would come up much earlier up to the point where it works they way it does now from the moment i start it.

PS. I got sparks on all plugs but haven't checked the leads/boots. Though I don't see how it could affect vacuum.

Cheers, Costas
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