I just got my cbr yesterday. It is a pain in the butt to start and it dies at stop lights. But thr bike has great power once its moving, no bogging out or power loss. Just can seem to get it to idle. I have messed with idle adjust but can get it to idle anywhere near the rpm it should be at. Just asking for some good places to start looking. This is my first supersport bike so im not tryin to play mr know it all. Just want to get my bike working good asap

 

What is it idleing at and what idle range are you shooting for?

 

How much have you turned in the idle screw?

I accidentally turned mine out a few revolutions and it was acting just like yours was. My "cure" for it was to continue to turn it out (just being a dumbass) until I realized that it has to be turned IN.

And I turned it in - a LOT - until I got it to idle again. Yours may just be that far out of adjustment.

 

Did you tinker with the idle adjustment? Honestly I would just start there...then move to the actual carbs and making sure they are delivering fuel properly..Has there been any aftermarket mods done to the fuel system? exhaust system?

I would investigate the carbs and idle adjustment....

 

Ok i changed it to a gravity feed setup after i found that the wire on the fuel pump that goes into the pump was broken and shorting. I have to adjust the idle screw when i start it then again about a mile down the road unless i want it to idle around 4000. Its sputters for about a minute when i start it up cold. Choke makes no difference. Its kinda like the old cars where the engine keeps going after the car is off. Then once it fires up it scream like nothing was ever wrong.

 

I just replaced the battery and it fires up much sooner now. It still dies if i dont hold the throttle. Choke doesnt seem to change anything. It will idle if i turn the adjuster up to about 4000 and i can slowly back it off but as soon as it hits like 2100 rpm it starts to drop and sputters out. After its like 180 degrees i can adjust it dont to about 1500 and it will normally hold an idle at a stop sign. Sometimes it still dies though. I noticed a few spiders running from the bike when i fired it up. Im assiming the previous owner never did more than an oil change. I added about 4 ounces of seafoam to my gas this morning but havent gotten to ride it since then. Just let it idle at about 2500 for about 10 minutes. I havent gotten a chance to get the plugs out cause im not too familiar with tearin down a supersport and this is day 3 of owning it.

Btw whats the easiest way to do a plug change on a supersport engine

 

These are all classic symptoms of carburetors that need to be cleaned.

 

Thats what i was leaning towards. New plugs and a carb clean and sync. I just dont have to carb knowledge to mess with a 4 carb set up. I can barely handle 1 carb

 

The carbs on the cbr's are not too difficult. I've always liked the keihin carbs they have had. They seem simple to me, I dunno.

They are really quite easy to work on. There are plenty of good resourses out there on how to clean keihins (they are all very similar, my old kwak had very similar carbs to the f1). Just TAKE YOUR TIME. If you are not a patient person, talk yourself through the process, it will slow you down.