hi guys and girls

i need help with my bike
ill try and describe everything i can,
right the bike bobs just like closing the throttle even when its fully open only in 3rd and above, it will only do this on the road, it runs pertfect whens shes in a paddock stand even when someone is sat on her,

shes had new fuel filter, spark plugs checked and reconditioned carbs.
she has been sat since feb last year due to an accident at work i decided to give her a new spray job full service new chain and sprockets, and a full clean.
i rode her today and she died 3 times on me when i was changing dwn from 3rd to 1st and then struggled to start again, i had a look in the tank and fuel was getting low so decided to fill her up and she seemed to bon worse i could b mistaken coz i just wantd to get home and off the road as theres no speed control.

any help would be greatly apprecited
i know its a long post guys i thought if u had all then info it may help more
thanks

 

should have said its a
cbr 600 f3 ft 1996
knew i forgot something
no wonder my boss hates me lol

 

Its kind of vague, but it sounds like fuel starvation for some reason. Next time your out, try putting the choke on and see if it gets better. If it does, then you definately have a fuel starvation problem.

Having said that, by spray job, I'm assuming you mean paint. You may want to make sure you have everything hooked up under the tank since I am also assuming it was removed for the paint job. There are some very critical vaccum lines that need to be hooked up or the carbs won't react correctly and the bike will stumble under high load, such as higher gears.

I'm sure others will have more to add as well. But maybe this will give you something to try.

 

cheers pal everything is hooked up as that was te first thing i checked and ill check the choke later today

 

so the bike is bogging down it this correct

sounds like you may have pinched a fuel line while installing the tank

 

maybe check the fuel filter. See how its doing.

 

cheers for tips lads but checked fule lines and fuel filter all fine, like i said it runs perfect when back wheels off the floor.
im thinking its electrical does anyone else it could be cdi box?

 

Its hard to tell without actually being there in person, but it still sounds like something is not correct with your fuel mix such as fuel starvation. The issue is when the bike is on the stand, there is no resistance or load on the motor. It spools up easily and it doesn't take much fuel to get the rpms up. When its on the ground and your riding it, the higher the gear your in, the more load that is on the motor. This is the area where fuel starvation really shows up.

If it were electrical, it would more than likely be rpm sensitive, not load sensitive like it is. It doesn't sound like anything is wrong with your ignition or it would do it at certain rpms all the time, not just under load.

I know you checked your fuel lines, but make sure your tank vent is not plugged. It will run ok initially, but without the vent to the gas tank open, you will not get the proper amount of fuel. A quick way to check this is to pop open the gas tank when it begins to bog. If you hear a whoosh of air, that means your tank is not vented. The vent will be a rubber hose leading from the bottom of your tank and hanging down into the frame. I've seen people plug these lines not realizing what they need to be open.

 

justasquid cheers for that info pal i will check thoes pipes i know they are connnected but they could be blocked so i will check them.
ive also changed the cdi box wasnt thee problem and also changed the coil packs again not the problem.

instead of fuel starvation can it be flooding the engine instead? or have i just made this up lol

 

cheers for all your help guys really appreciate it but the problem has gone the direct air lines came loose so at speed where getting pushed behind the fairings where as stood still the hoses would pop back in to place so just need fitting in to place