Carburettor question

38141

I've got a loud tapping sound coming from cylinder a little backfiring going on as well. Pulled the spark plug and its black (side electrode) and white (center). All this tells me from my research the fuel mix is lean. Cuts out too at start so it's probably the idle mix I need to look at in carbie. The bike is a suzuki gn125 (2003/4 year) and I'm trying to find where relevant screws/jets are on this carburettor to adjust. I don't have the manual for this bike unfortunately and was wondering if anyone has any experience with this bike, or carburettors such as these:cool:?

Green_Martian

38141 wrote: »

I've got a loud tapping sound coming from cylinder a little backfiring going on as well. Pulled the spark plug and its black (side electrode) and white (center). All this tells me from my research the fuel mix is lean. Cuts out too at start so it's probably the idle mix I need to look at in carbie. The bike is a suzuki gn125 (2003/4 year) and I'm trying to find where relevant screws/jets are on this carburettor to adjust. I don't have the manual for this bike unfortunately and was wondering if anyone has any experience with this bike, or carburettors such as these:cool:?

Don't know much about it myself but i know a man who will, where are you based mate???

38141

Green_Martian wrote: »

Don't know much about it myself but i know a man who will, where are you based mate???

I"m abroad for the foreseeable future

38141

I'm tryin to get the idle jet tuned first, but unfortunately Its not accessible externally as the float bowl is covering it and must be taken off first. But doing this then means that I cant keep the engine running to check if its idling correctly. It means I have to take off the carbie, adjust the idle gas jet, put the whole thing back together each time and keep doing this until I get it right, i did it once already and it took me the whole afternoon!

Green_Martian

38141 wrote: »

I'm tryin to get the idle jet tuned first, but unfortunately Its not accessible externally as the float bowl is covering it and must be taken off first. But doing this then means that I cant keep the engine running to check if its idling correctly. It means I have to take off the carbie, adjust the idle gas jet, put the whole thing back together each time and keep doing this until I get it right, i did it once already and it took me the whole afternoon!

Yeah it sounds like thats the only way to do it with Carbs mate, fiddle with it put it back together to see if it works, if not do the same again and again until its right

38141

By closing the screws on the jets am I increasing or decreasing the petrol going into the cylinder?

Also, there is a plastic cover over the idle(pilot) jet, is this to be removed or kept in place in order to ride the bike? What the hell is a plastic cover doing over the jet, that's going to block the thing from taking in any petrol from the float bowl?