Misfire

[Simonic]

So gentlemen. I've just bought this bike. It was a cheap deal so iwas ready to do some work. When i looked at the bike and heard it running it had a misfire from one cylinder(likely number 2)
It didn't look like it had a service for some time so iv'e done.
New plugs,air filter,had the injectors cleaned down at injectortune,cleaned the tea bag.
Got it back together and it's still the same.
Also the 'fast idle when cold' does not seem to work.
When the bike is on tickover i'm getting an intermittent pop thru the exhaust,like there is unburnt fuel getting in there.
I'm no great whizz with fuel injection so i'm a bit stumped......

[KiwiCol]

Your misfire & ignition switch issues could be related.  Bit too early in the morning for me, but there's 2 maps, 1 is for starting & 1 is for running, if you've got a bypassed clutch switch, it won't be using the right map.

Do you have to pull the clutch in to start it?    The popping / backfiring will be fom the pairs, I'd say, you can either block them off or get rid of entirely with no ill effect - actually runs better, but you'll loose the popping on deceleration.

[seth]

Tho youve cleaned the teabag filter did you wash out the high pressure filter with carb cleaner too ?
Did you clean out the fuel lines before rebuilding everything as you might have pushed more dirt into the system ?
Have you tried swopping over the coils to see if the miss-fire changes sides ?
Have you checked as many connections in the loom as you can to eliminate and bad or corroded connections ?
Where are you if there's someone near they could swop parts of the same model of 14(upto end of k4 (twin can) is the same and from k5 (single can)is the same but the parts you need to try aren't the same across models) to try and fine the problem .
I'm in north East Scotland if you can get here happy to try things to sort it .

[Simonic]

Hi Gentlemen.
Thank you for your replys.
I had to rewire the std ignition switch to get it to run.
I'd wondered about the coils and i can swap them over.
I'll do it tomorrow

[Simonic]

Your misfire & ignition switch issues could be related.  Bit too early in the morning for me, but there's 2 maps, 1 is for starting & 1 is for running, if you've got a bypassed clutch switch, it won't be using the right map.

Do you have to pull the clutch in to start it?    The popping / backfiring will be fom the pairs, I'd say, you can either block them off or get rid of entirely with no ill effect - actually runs better, but you'll loose the popping on deceleration.

Hi There. The pattern ignition switch did not power the bike so i've had to go back to the suzuki item.
I've fired the bike up again this morning and number 2 cylinder is taking longer to get warm than the others. I do need to pull the clutch in to start the bike.
I'm going to swap the coils over later today.
Thank You for your input

[Simonic]

Tho youve cleaned the teabag filter did you wash out the high pressure filter with carb cleaner too ?
Did you clean out the fuel lines before rebuilding everything as you might have pushed more dirt into the system ?
Have you tried swopping over the coils to see if the miss-fire changes sides ?
Have you checked as many connections in the loom as you can to eliminate and bad or corroded connections ?
Where are you if there's someone near they could swop parts of the same model of 14(upto end of k4 (twin can) is the same and from k5 (single can)is the same but the parts you need to try aren't the same across models) to try and fine the problem .
I'm in north East Scotland if you can get here happy to try things to sort it .

Hi There. When i cleaned the teabag i did put some carb cleaner into the hi pressure filter and i cleaned the fuel lines out. I've pushed and pulled at all the connectors i can see as the bike is running.It seems like it's number 2 that's not right as it's taking longer for that header to get warm.
I'm going to try swapping the coils over today.
Thank You for your input

[Hooli]

If swapping coils doesn't help you could try swapping injectors around. I know you've had them cleaned but it's never worth trusting something 100% until you've tested it yourself.

Plus why they are out you can recheck the tiny filter mesh where they fit to the fuel rail, it wouldn't take much dirt to partly block that.

[rollerfish01]

Hi Simonic, my bike has similar situation with you. When I checked the pressure of cylinder 2, it was significantly lower than the other 3 cylinders.
May worth a look. 

[Simonic]

Thank You Hooli,that's worth a try. The injector filters are new tho.

[Simonic]

Rollerfish01,by pressure do you mean a compression check? if so ,how did you approach the problem? Engine strip req'd ?

[Hooli]

Thank You Hooli,that's worth a try. The injector filters are new tho.

I'm just thinking of a bit of dirt out of the fuel rail or pipe work that your flush dislodged but didn't clear out. It sounds like you've done everything else I can think of.

[shanered6]

I would check your number 2 plug just incase you nocked the plug gap when refitting it , i say this coz i did the same thing on mine and it took me ages to find it ?  mainly coz i just thought cant be plugs ive changed them ... but it was a closed gap !

[Hooli]

I've had a brandnew plug DOA before, not for a bike but it does happen.

[rollerfish01]

Rollerfish01,by pressure do you mean a compression check? if so ,how did you approach the problem? Engine strip req'd ?

Yes, I did the compression check as stated in the service mannual, chapter 2-27 "PERIODIC MAINTENANCE: COMPRESSION PRESSURE CHECK",
You can find it at the downloads page.

Hope you can locate the problem and fix it soon ! 

[Simonic]

Today I swapped the coils over and the problem did not travel. Then I disconnected the PAIRS. This has cured the problem. I just taped over the ends of the pipe and the tube on the head and it stopped popping straight away. Just to make sure I reconnected the system as the problem came back. I know a lot of you guys disable the system, but how does it work? Do many of you use the blanking plate option or just block it off? I'd be interested to know. Thank you so much for your help everyone.