Yamaha TRX850 Enthusiasts Forum

Ok so I recently changed emulsion tubes on my trx and I had problems getting it started I then set the floats heights correctly but was having trouble putting float bowl back on as the brass over flow tube was pushing down on the float and stopping the fuel coming into the bowl I had a spare set of carbs off previous owner which did have these brasse over flow tubes so I put them on the bike and it ran perfect around my estate however when I went to go on a longer ride about 5 minutes into it bike started playing up it would idle and it was popping and banging at 3000 revs and flames coming out the exhaust anyone got any thoughts on why this might be happening? Thanks. Luke.

Did you make sure the carbs are seated correctly in the mounting rubbers, I have found this difficult.
Are the mounting rubbers in good condition, if they are cracked or perished, they will need to be replaced.
Did you replace any seals in the carbs, if not they may be leaking.

You have a weak mixture and / or the intake`s drawing air somewhere. Go back over your work meticulously, you`ll likely find something.
I don`t understand the refitting of the float bowls issue though, could you take pictures and post them up?

From memory, it's a fiddle to get the brass tube in the right place, otherwise it jams the float from opening fully and liable to bend the height adjusting tab

Sorted the problem was spark plugs one of the rubber seals on the ht lead was actually on the spark plug stopping the ht lead from connecting properly runs sweet now. Might be running a bit rich though I think the needle clip was on the third one down position so maybe thats why im not sure, going to take it for a longer ride tommorow then check spark plugs see what they tell me. Thank you for your replies I will take these into account next time I mess about with the carbs which is hopefully never again