Re. backfire on a ZX12R

[Smitty]

I have an issue people.... i have a ZX12R that i had for about 3nths.

the bike is great in all aspect, but i have a slight problem... when the bike is reved at over 7000rpm, i have a backfire sound....

Could this be from a leak somewhere lettiing pressure from the exhaust or could it be somthing else.

Please help...

...pm sent

[deafwish]

Disable the KLEEN system.
That should sort out the crackling sound.

Besides just removing it without installing a PC3 is plain silly.

How does the KLEEN system effect air fuel ratios to warrant you saying that you need a PC3 to remove the KLEEN?
It works well after the combustion process!!!!!!!

[FrogZ]

Its fucked mate !!! And its not worth nothing either because they dont make em anymore.
BUT me being a nice guy, I will buy it off you, cheap of course.
Just the frame will do....

[Wattie]

the pc3 would get the mixture spot on, and would reduce popping from running rich.

[kawa zx12R]

Sounds like KLEEN, but mine doesn't do it.

You don't rev it past 7000RPM Hoffy

Id still kick your ass without hitting 4,000rpm

nah seriously the KLEEN makes the bike very *poppy* when you get off the throttle at high revs, it has to be it.

hoffy i'll try the KLEEN system and see what that does.... it worth a try...

if all fails the mechanics should now what is it....

[FrogZ]

Umm why have we got 2 threads going for this and tyres (just out of interest) ??

[Jonno]

Disable the KLEEN system.
That should sort out the crackling sound.

Besides just removing it without installing a PC3 is plain silly.

How does the KLEEN system effect air fuel ratios to warrant you saying that you need a PC3 to remove the KLEEN?
It works well after the combustion process!!!!!!!

Did you do this on your very own 12R, if so how did it perform over the following weeks?

Well it didn't work on my chainsaw, so it can't work at all now can it!

I am not going to argue with an expert and I could not be stuffed doing all that searching to find the info' to convince you.

All I know is it does not work on the 04 -06 model ZX12R at all, 2003 I am not sure, many have tried and were caught with shocking states of tune even with a PC3 and custom maps.

Remember there were 140 changes to this bike by the 2003 model, a few more from 2004.

[Gosling1]

I have an issue people.... i have a ZX12R that i had for about 3nths.

the bike is great in all aspect, but i have a slight problem... when the bike is reved at over 7000rpm, i have a backfire sound....

Could this be from a leak somewhere lettiing pressure from the exhaust or could it be somthing else.

Please help...

Jonno's links are worth checking out. Don't bother with the KLEEN removal/modification if yours is a '04 or later. Its worth doing on the early models, but there are other mods that need doing as well......

My '05 12 popped and banged like a bastard on the over-run if I was giving it the berries up to red-line, then shut the throttle quickly, it was really loud and gave me the shits. The only mod was a Yoshi RS-3 can.

Funny thing though, I have changed *nothing* at all in the past 18 months, and the popping/banging has gone ......I have no idea why this has happened, but it has just dissapeared as the kilometres have racked up (24k now.......and the stock air-filters have *finally* been replaced with some BMC's !! )

[kawa zx12R]

gosling

i've heard everyone say do the kleen suystem.... why should it have such an impact on the running of the bike... i have a 2000 zx12r, what mods could i do on it....
the sound in bearable at this stage... it has gone worse, but it definite hasn't gone... but its only at 7000rpm not ant any other stage.

Also this goes out to all the melb riders.... looking for a good workshoip for the beast.... i live in altona...

any help would be great.

[Jonno]

Ok I have done some research to refresh my memory, I do not want to see you chase your tail.

Here are a few things to check/swap out before clutching at straws in the kleen air, now listen up ok Simon says..

From everything I understand on this problem it can be any of the following from least likely to most likely IMO:

ingnition stick (not likely on deceleration)

ECU/CPU

dirty injector not closing down properly

and my favorite:

the Cam pickup sensor, has been known to do this on your exact model

Another thing, if you change to aftermarket air filters, pipe, timing plate you will need a pc3 to get the best from them. In fact in hindsight the PC3 should have been my first purchase, can make a big difference even on a stock bike with the right map and/or dyno tune
Anyway there is a lot you can do on the "A" model without a PC3. See 3rd link above
Hope that helps

Jon

ps; let us know how the kleen air thingy goes, you know you will do it!

[Gosling1]

......i've heard everyone say do the kleen suystem.... why should it have such an impact on the running of the bike... i have a 2000 zx12r, what mods could i do on it....

with a 2000 model, removal of the KLEEN system is basically *mandatory* if you fit a pipe/filters etc. With the later models, they scored a lot of changes, not the least of which was a change from a 16-bit ECU to a 32-bit ECU. This change alone has made removal of the KLEEN system on the later models less of an issue.

Just check out all of Jonno's links, and there are a heap of other good ones that he has posted on the Oz zx12 forum - you can spend *days* in the links section I know I have !!!

All you really need to do is, in this order:

1. Sort out your suspension first, no point in horsepower mods if it handles like a pig;

2. Put braided brake lines on it. No point in horsepower mods if you can't STOP the bastard from Mach 16 ;

3. *THEN*, start with a either a can, or full exhaust if you can afford it, better air filters, and a PCIII, mapped to suit your 'zorst and filters.

Thats it. 12's don't need anything else for *dinkum* street riding, as far as I can tell from 18 months of flogging mine around !!

[FrogZ]

..and just to open ANOTHER Pandoras Box, what about a Muzzy ignition advancer

[Jonno]

..and just to open ANOTHER Pandoras Box, what about a Muzzy ignition advancer

Already mentioned as the timing plate mate, a few other aftermarket ones around

But that advance of 4+degrees makes a nice power increase, ok the worm has escaped will it leave the building.

[Smitty]

...snip...

All you really need to do is, in this order:

1. Sort out your suspension first, no point in horsepower mods if it handles like a pig;
2. Put braided brake lines on it. No point in horsepower mods if you can't STOP the bastard from Mach 16 ;
3. *THEN*, start with a either a can, or full exhaust if you can afford it, better air filters, and a PCIII, mapped to suit your 'zorst and filters.
Thats it. 12's don't need anything else for *dinkum* street riding, as far as I can tell from 18 months of flogging mine around !!

...aaah such words of wisdom, such sagacity
from the ol'fella

...spot on again Gos
couldn't agree more

[Duane]

is this a sports tourer owners love shack thread or something,

Smitty & Gos get a room!!!