Heavy backfiring on overrun. AT RD03 1988. Here in Thailand no Honda-big-bike-service. A good mechanic told me that this comes from the carburator, something allows too much air into the fuel? anybody can help me to find what exactly has to be done or which part needs to be replaced?

Can be the choke, the carburators, air filter etc...

got o Honda Trail Bike Forums (english) or africatwin.de (german) they can help you if you provide a more detailed description. e.g. when it backfires (going downhill maybe)

What happens almost to all AT´s is that the choke cable gets blocked so the air intake is always open. (Symptoms: backfiring, black smoke, black end of exhaust, high gas consumption) to fix that is not rocket science. Take out the two screws at the carburetors, take out the wiring at the top, get it out completely, dismantle it, clean it all very well, oil it, put it back together again. Just remember where to put it back again (take photos maybe!) and take care about the screws they are plastic and with too much power they break fast!) this works for the RD07, 1993. 1st time 2h should do.

Ps.: in BKK a lot of people made good experiance with:

Dynamik Motors Big bikes (BMW, Harley, Ducati, Japanese, whatever). General maintenance and difficult repairs. Yut is more like a bike lover than a shop owner. He also has a workshop near the shop where riders can work on their bikes by themselves.

Contact: Mr. Yongyut.
Open: 9:00 - 19:00
Sunday Closed 259/1-2 Visuttikasat Rd, Bangkunprom, Pranakorn, 10200 map

Tel 02-282-9999, 02-282-1755
Fax 02-281-0322

Email: yutdynamic@yahoo.com
GPS: N13.76103/E100.50612

taken from:
http://www.bkkriders.com/shops/

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