Exhaust expertise in Thailand

[AllanB]

I have written before about the silencer problems on my old NV400 and have spent quite a few months experimenting in order the get the correct back pressure, which appears to be critical on this high powered bike (43bhp from just 400cc) . However, although I think I am close in terms of back pressure and the bike is now quite powerful and torquey, the end result is crude and the bike sounds that way too.

I was wondering if there were any real exhaust specialists in Thailand, hopefully in the North-East. The bike is a rare Jap import, so chances of a stock item are zero.

[ktm jeff]

Allan If the header diameters are correct , the bends and lengths will be dictated by the space available within the frame around the engine , and the old mounting points. A road legal (quiet) exhaust from a similar bike , 400 cc V4 Honda -VFR NC or an CB 400 having similar characteristics to your bike , should do. Then a rolling road session to fine tune the beast.

[AllanB]

I guess I should have been more specific, I meant the silencer section and to be even more specific the baffles.

[ktm jeff]

If your final piece of the puzzle is the silencer (muffler) , i would go for on off a bike as close to yours as possible in terms of power , engine torque , revs and character. Unless you cut a can open , it will be difficult to know the design , size and number of baffle plates inside. Are you trying to make a silencer of a different shape / design ?

[AllanB]

If your final piece of the puzzle is the silencer (muffler) , i would go for on off a bike as close to yours as possible in terms of power , engine torque , revs and character. Unless you cut a can open , it will be difficult to know the design , size and number of baffle plates inside. Are you trying to make a silencer of a different shape / design ?

The silencer on my bike has removable baffles and a local workshop made me a new baffle for 600 baht fashioned rather crudely, with lots of steel padding, which made the bike very quiet in order to pass the Thai MOT

But it was way too restrictive, so I have been playing around with this and the original straight through baffle, which was on the bike when I bought it.

I will look around for something existing, which fits my silencer enclosure, but fear I would be wasting my money, since the engine is a bit of a special.

But thanks, it is worth a look.