Trials Australia Forums

Hi everybody Can someone please advise of effects of fitting a ty250C airbox lid to my ty250b The C lid has air intake hole in it The bike has a UNI filter fitted Can I up the jet size for more power Thank you

They are pretty sensitive to the amount of restriction created by the airbox. The B model jetting is different to the C and D model jetting and the only difference I've ever found is the airbox design. At one time I had the early airbox with the air entry holes in the side and I fitted a late model lid to it. It wouldn't run properly like that and to get it to run properly, I taped over the holes in the side of the airbox and used the D model jetting.
Less restriction in theory will allow the motor to make more power but good luck getting the jetting right.
Very recently I fitted a 26mm OKO to that bike and am running no airbox, just a pod filter and it runs beautifully. The engine response to the throttle is noticeably faster than it was with the D model TY250 carby. Long term I want to make a large volume airbox but haven't got there yet

Thank you David cheers