3tj starting problems from cold.

[Tomahawk]

My bikes being a pain to start from cold. Sometimes you can catch it with no choke on and it will go but most days it just wont fire straight away. If you give it full revs trying to start it, it will flood itself and wont rev. But if i hold it at about 1/4 revs it will try to fire up and after about 5/10 mins of it pissing about at 1000 revs it will sort of break through the rough patch and fire right up. Whats annoying is that once it has start it takes choke straight away and then i dont get the problem again until its cold. Any suggestions on what it could be?
Cheers tom

[Mad Ad]

Sounds carb related to me!
I had an FZR250R that did something which I put down to the float needles sticking as turning the fuel off helped it clear quicker. I never managed to fix it completely though but I didn't change the needles.
I would recommend a complete rebuild on the cards with new float needles and jets and change the emulsion tubes, main jets and needles at the same time as the tubes and needles are known to wear!!

Hope you mange to get it fixed!!

[Evilchicken0]

Change the sparkplugs, you'd be surprised how they can affect an engine even if they spark they can be a bit duff.

When you start from cold does the fuel pump time out, or does it take a long time ??? If it does then it could be the float valves but that would probably give a poor idle too.
So, first off would be take the carbs off and clean them, have a look at the diaphrams to check they're not pin holed. When you put them back on it's easier to attach the throttle cables first.
Renew the fuel filter, clean the filters, one where the fuel hose attaches to the carbs and the other on top of the fuel tap (in the tank).
Check the airbox is properly sealed to the carbs.
Get the carbs ballanced - this could be more of where your prblem is.

Next up ... how's the battery ??? Check the terminals are clean and the wires are tight. With the engine of turn the lights on, if they dim in 30 seconds the battery could be a bit low and maybe needs replacing. You can put an uprated battery in and the engine will p1ss over.

Lastly and most difficult .... maybe the valve clearances need doing. You'll need a compression test both wet and dry to find out though.

[Tomahawk]

I've had new carbs put on the bike which made it run a lot better than before but i had the starting problems with my old carbs. The fuel pump times out it im guessing its gets all the fuel through straight away. I've had new spark plugs and a battery in the bike about a month ago. I had the carbs cleaned this week because i changed the downpipes and had new tyres put on. Tomorrow i will check the air box and check the carbs. Im trying to sell it at the moment so need to try and fix it.

[Evilchicken0]

It's not a great place to be in, you don't want to spend but you don't want to sell it with a problem.

Check the fuel filter, have you checked the EXUP isn't stuck ???

It sounds like you've done eveything other than the valves. I'd get a compression test.

[Tomahawk]

Someone is coming to look at it on sunday i told him about the problem and he didnt really seem to mind. Ive put a new fuel filter in, And just put new downpipes on and checked the exup and everything when i did that and it seems to be opening fine. I took the air filter out earlier and it seemed to start a bit better but dont really know how to cure the problem with the air filter in. I will try to get a compression test done but if it is the valves i really dont have the money to get it done so i will probably have to take £100 off the asking price i guess.

[Evilchicken0]

Well if he's aware of the problem then you don't have to provide a correct diagnosis, that's up to him to cure.
A garage would charge about £300 for valves ... obviously that can be different depending who you go to.

But see what he says