Triumphrat

Bonnevillain · 06-06-2008

1973 Bonneville.

The bike came with T120 mufflers on 1 1/2" pipes. I believe the stock pipes for this model were 1 3/8. This explains why the T140 mufflers I bought won't fit. However, the book lists 71-3723, which is a T150 muff. Did T150s come stock with 1 1/2" pipes? If so, I'll go for the 71-3723s. If not, does anyone know where I might find some reasonably accurate reverse-cone (cigar) repros that will fit on a 1 1/2" pipe?

DAGAD · 06-09-2008

Hi Bonnevillian, I guess no one else wants to talk about silencers & pipes? The T150 silencers were 1 1/2" inlet and the T120 / T140 were 1 5/8". If you have the bigger T140 ones then all you need to do is get a sleeve to pack out the difference.
Roy.

Bonnevillain · 06-09-2008

That's odd. I bought 71-4159 EMGO silencers, which are supposed to be for the T140, and the inlet is exactly the same size as the pipe, meaning that there is no way they are going on there.

Okay, I found the EMGO catalog, and they are listed as 1 3/8 for the T140 from '73 on, and my pipes are certainly not that small.

Looks like I need 71-2382, which were used on early '73s. Burton Bike Bits states they are made to suit 1 1/2" pipes. I guess I either have an early-year model or someone changed out the pipes.

Thanks for pointing me in the right direction, DAGAD.

DAGAD · 06-10-2008

Come to think of it, those 1 3/8" ones will be for the T100R Daytona.
Roy.

htown16 · 06-10-2008

I thought almost all 750's came stock with pipes that push directly into the exhaust port. These are 1 3/8" and are not enlarged to mount over a spigot and the mufflers (silencers) are the same size. I'm not sure of the date (1980?) but I think they went back to mounting them over an external spigot like the 650's. However its not unusual for someone to have converted the push-in style head with aftermarket spigots so that 1 1/2" that mount over the spigot could be used along with earlier style mufflers. This may be the case with your bike.