Carb Settings

[grahambaskin]

Hi guys,

I cleaned out the carb on my gas gas 280 2009, and was looking for advice on how to go about setting up my carb correctly, the right air/fuel mix to allow my bike to run crisp and at its best. any pointers would be great

thanks

[chewy]

most folk can adjust all they need with the air screw or mixture screw just set it ticking over as slow as possible and screw in or out untill it runs smoothest if its banging and lumpy (dare I say like beta's tend to) it's too rich if it hunts (speeds up & slows down) & or knocks when you snap throttle open it's too weak. I think it's a mixture screw on your bike so it would be out to richen mixture. if it is an air screw it's the opposite. (some carbs meter the amount of air before the pilot jet e.g mikuni on beta and some meter the total amount of fuel mix after the jet.) It's unlikely you would need to change jets at this stage in the life of the bike but they must be clean particularly pilot jet(it's tiny one nearest engine on gas gas)from memory.

[davet]

Back the fuel screw all the way in then unscrew 3 to 3.5 turns. then just set the tick over.

Hope this helps.

[grahambaskin]

Thanks for that, i'll try playing with the settings on the carb. She is a little revy and slow to reduce the revs would this be my problem.

[davet]

What you need to do first is make sure the rest of the carburettor is clean inside, you need to remove it from the bike, take the 14mm brass nut out from underneath & remove the float bowl, line everything up on the bench in order & remove the pilot jat & starter jat. blow them out with compressed air & refit back together... By the sounds of it I bet the pilot jet is blocked!!

With the fuel screw (the one to the left of the idle screw) turn it all the way in, then back it out 3.5 turns, this is a good base setting but all bikes run differant.

With the tickover screw you need to just start the bike up & turn it in until the bike is just ticking over nicely or where you like it, if the bike is running lumpy (rich) then just turn the fuel screw in a quarter of a turn at a time until it runs better. If the bike is hunting for fuel (weak) then turn the fuel screw out until it runs better...

Hope this helps.

[grahambaskin]

Thanks a mill for your advice, i had taken the carb of and cleaned it with compressed air but never cleaned the jet, i will due this at the weekend and let you know, cheers.

[miner]

3.5 turns out the norm then?  Would 2 be leaner? First run out after rebuilding the carb... bike felt a little flat at initial opening... maybe a little lean? 

[lineaway]

Lean on the pilot as it is a fuel screw. Might remove that oring on top. Could just be sucking more air.

[miner]

Could be... worth a try... 

[miner]

Tried 3.5 turns... pop definitely restored.