Cbr 600 running issues ..

[Martylee]

Had some issues with my cbr with it being very slow and wouldn't go past 100mph.
Though it was restricted and removed the carbs and turns out it wasn't just the carbs where all crappy inside..
A good clean and what a difference it has made..
Fast forward a week and the bike lost power and sounded like it was running on two cylinders...
Stripped down again to find fuel pouring into the first too carbs .. so once again Stripped the carbs and cleaned..
The floats where what I thought where the problem so after a really good clean the bike seemed even better but now has a lot of popping ?
I have searched Google but no answered related to this problem and being my first 600 I have nothing to compare it too?
Any of you guys have any ideas ?

 

[Martylee]

Should have said the popping is from the exhaust when you come of the power

 

[rikrobson]

sound like there is fuel in the overrun. are the float needles sealing correctly. you chould be able to get new needles. IIRC they hace rubber tips that do the sealing. these could be damaged in the cleaning process and are letting fuels past.

 

[Tinbasherdan]

Over fuelling on overrun, wouldn't worry about it, my r1 pops and crackles like mad on overrun, and if it's feeling really naughty I get the occasional flame too

 

[BrokenBiker]

My bandit used to pop a lot on over run...I quite liked it..not a huge problem just sort out the 2 carbs flooding so it runs properly

 

[Martylee]

Since I cleaned the floats and float bowls it seems to be running fine .. just wasn't sure on the popping but yeah it is a nice kinda popping but didn't want it damaging anything

 

[Tinbasherdan]

If you're exceptionally unlucky and it's over fuelling way too much you can blow the can apart. Has it got an aftermarket can?

 

[roofman]

clean them again and put an in-line filter on the fuel pipe...sounds like the tank has some crud in it,often caused by keeping the tank half full or less and condensation attacks the top half leaving a fine layer of rust. Had the same proplem on my 1200 bandit and kept leaving the smallest of particals under the float needle valve but enough to lift it off its seating and fill the bowls.

 

[jordan1]

Since I cleaned the floats and float bowls it seems to be running fine .. just wasn't sure on the popping but yeah it is a nice kinda popping but didn't want it damaging anything

Have you checked and set up the float levels as per the manual?, and balance the carbs.

 

[BrokenBiker]

clean them again and put an in-line filter on the fuel pipe...sounds like the tank has some crud in it,often caused by keeping the tank half full or less and condensation attacks the top half leaving a fine layer of rust. Had the same proplem on my 1200 bandit and kept leaving the smallest of particals under the float needle valve but enough to lift it off its seating and fill the bowls.

beat me to it...as i was driving home i remembered that i had a similar issue with my cbr400 where the inside of the tank was filthy and crap was causing the needles to sit high...

i cleaned the carbs god knows how many times but still got the same recurring issues with every tank of fuel...then a mate said he could steam clean the inside of the tank for me, eliminated every problem i was having with fuelling...i put an inline filter on after that but it never got dirty enough to need changing

P.S i had an afer market ali tank fitted by previous owner before anyone mentions about steam cleaning a steel tank and causing rust

 

[Martylee]

Yeah I do have an aftermarket exhaust ..GP style can...
No rust or debris inside the fuel tank and already has an inline filter fitted
And as for the float adjustments ..there isn't any...they all appear to be even and in good condition I will double check though..
The only thing I haven't done is balance the carbs as this had been done by a garage just before I purchased the bike.. but I will have a look at it myself once I've got some gauges

 

[Martylee]

Thank you for all the ideas though

 

[BrokenBiker]

Yeah I do have an aftermarket exhaust ..GP style can...
No rust or debris inside the fuel tank and already has an inline filter fitted
And as for the float adjustments ..there isn't any...they all appear to be even and in good condition I will double check though..
The only thing I haven't done is balance the carbs as this had been done by a garage just before I purchased the bike.. but I will have a look at it myself once I've got some gauges

if you have stripped and cleaned the carbs a few times they will probably need balancing but you should be able to hear/feel which ones are out, if any...ive stripped carbs and gotten away with not balancing them before, toher times they have all been well out...i balanced my fathers bandit with my hand against the air inlet on each carb...alter until they feel the same, its not 100% accurate but good enough to get him power wheelies in 4th...on a closed road obviously...

 

[jordan1]

Yeah I do have an aftermarket exhaust ..GP style can...
No rust or debris inside the fuel tank and already has an inline filter fitted
And as for the float adjustments ..there isn't any...they all appear to be even and in good condition I will double check though..
The only thing I haven't done is balance the carbs as this had been done by a garage just before I purchased the bike.. but I will have a look at it myself once I've got some gauges

I'm sure you know to check the ignition system as well as setting the carb float levels before balancing.

 

[dobbslc]

Did the carbs seal correctly in the rubbers? An air leak will also cause popping on the over run. Most bikes I've had apart have adjustable floats by bending the metal tang on them.

 

[BrokenBiker]

Did the carbs seal correctly in the rubbers? An air leak will also cause popping on the over run. Most bikes I've had apart have adjustable floats by bending the metal tang on them.

im sure the cbr600 has some adjustment...i had a 600f and am sure i had reciepts with it for carb work and adjustments

 

[Tinbasherdan]

Aftermarket end can will probably making it run rich, hence the popping. If it's picking up properly, no holes in the power anywhere, no lumpy running etc I'd say it's running as well as it will be, and don't mind a bit of overfuelling on over run

 

[norlander]

popping on the over run can be caused by lean mixture as well an air leak as mentioned by one gent already.

What do your spark plugs read? maybe not as good a guide as it used to be with the lean fuels now , but running on 98 works for me.

Plug leads and caps all in good shape? dodgy plug cap can be right teaser.

Nice clean earth for battery.

At the end of the day tho , as Tinbasher says, aftermarket can and also air filters can make it difficult to completley dial out popping.