fzr400rr advice

[bigrich]

Hi all,

I have a grey import 1989 400rr I love the bike and it is very heavily modified (I will get some pics up soon)

I have owned it for 2 years and most of that time it has smoked black smoke when first accelerating hard or on hard throttle pull back. It doesn't affect emmisions. Or power, but at a constant speed it will pop and splutter. My mates seen to think a rebuild is needed. I'm tempted to de coke my pistons first. Do a fuel filter and oil filter change and re tune my injectors my bike doesn't burn oil and doesn't seem to be losing any. Do u think I'm on the right track or do u think rebuild

I'm thinking if a rebuild is needed maybe a engine swap.

Any ideas?

[apsolus]

its injected? check the program might be to rich. if its carburated check jets and fuel bowl level. sputtering is most likely fuel related not mechanical

[bigrich]

Sorry slip of the mind mine has carbs. I meant retune my carb jets

[Fzrmike33]

You dont want to have to rebuild the engine that will cost a small fortune, better off buying a used motor, or droping a fzr 600 motor in it.

[sweekster]

To me this sounds rich and usually a good synchronizing session of the carbs can take care of that.

[bigrich]

I don't particularly want a rebuild. I'm hoping to drop a 600 motor in more and more now. What would u recommend yzf600 motor or fzr600 motor

I thought a carb clean and set up for now would suffice tho and maybe a de cokein and fuel filter and oil filter change
What u reckon?

[RoadDogma]

Unless you are talking "fox-eye" an FZR600 motor will not bolt-up (it lacks the upper mounts) and does not have proper counter-sprocket off-set, so you will want a YZF600 motor. The YZF motor makes better power anyway.

[dru86]

To me this sounds rich and usually a good synchronizing session of the carbs can take care of that.

+1 black smoke = too much fuel
grey smoke = oil
white smoke = coolant (or S#it loads of oil)

The Poms call the yzf600 a fzr600 too. AS RoadDogma said If you're putting a fzr600 motor in there the one you want is a 94 onwards, know as the foxeye.

[bigrich]

Ok so I got two options a yzf600 motor or a 94 fzr600 motor

And adjust my fuellin on 400rr motor for the time bein

[pefrey]

Sooty smoke = running rich. Is the tail pipe covered (inside) with black soot? Adjust / clean / troubleshoot your carbs.