MX Exhaust Question

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johnu
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MX Exhaust Question

Post by johnu »

Hi All,

Can anyone tell me if my header pipe looks like the stock item.... I think it is! Also it runs really close (fag paper clearance) to to the bolt head on the rear engine mounting plate. And is that hideous looking bracket that is right above the end of the header to attach the silencer to.

I am also looking for the smallest silencer I can find to use for mx with this header, any suggestions?

Thanks,
John.
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kommando
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Re: MX Exhaust Question

Post by kommando »

Info was for wrong bike.
Last edited by kommando on Tue May 05, 2020 7:31 pm, edited 1 time in total.
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JB
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Re: MX Exhaust Question

Post by JB »

The hideous bracket on the frame looks like the strengthened silencer bracket for the twin silencers your bike was originally fitted with, the earlier version was a known weakness that nearly always broke!
Your downpipe looks like the original one, try some fine grade wet/dry paper in the area of where the silencer fits over it, look carefully and you might find a part number stamped on it, which would prove that it is the original one. HTH
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2manyrides
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Re: MX Exhaust Question

Post by 2manyrides »

My take is;
You have the correct type header pipe. Though the mx came with a more “black chrome@ looking finish than what yours looks like. I suspect yours is from a t or ss model, but still proper diamentions.

Yes, the tail end runs close to the bracket bolt.

Yes, the beefed up hanger on the tr5mx for the front mount of a muffler is improved over previous b50’s but bolt up between the two is the same.

There are pattern correct mx mufflers out there that are repop as opposed to the one into two system your mx came with.

You probably wouldn't go for this, but a rocky, bates or other similar aftermarket “upswept” shorty can be installed and the angle on it twisted round to look proper against the bike when attached to the existing header. Thus, no extra fabrication needed besides a bracket at the tail end.

Later, if I can find a link or photo, I will post it.
72 B50SS bought in 74, I'm the second owner
74 TR5MX bought in 77-new, I'm the original owner

Which one to ride today?
johnu
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Re: MX Exhaust Question

Post by johnu »

2manyrides wrote: Tue May 05, 2020 5:36 pm My take is;
You have the correct type header pipe. Though the mx came with a more “black chrome@ looking finish than what yours looks like. I suspect yours is from a t or ss model, but still proper diamentions.

Yes, the tail end runs close to the bracket bolt.

Yes, the beefed up hanger on the tr5mx for the front mount of a muffler is improved over previous b50’s but bolt up between the two is the same.

There are pattern correct mx mufflers out there that are repop as opposed to the one into two system your mx came with.

You probably wouldn't go for this, but a rocky, bates or other similar aftermarket “upswept” shorty can be installed and the angle on it twisted round to look proper against the bike when attached to the existing header. Thus, no extra fabrication needed besides a bracket at the tail end.

Later, if I can find a link or photo, I will post it.
That's great thank you! I am perfectly fine with aftermarket, this bike will be far from original. Photo or link would be awesome.
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Re: MX Exhaust Question

Post by johnu »

I could actually make my own silencer tbh if I had dimensions. How critical is the silencer on these bikes?
the pic below is what I'd hope to end up with roughly maybe a little longer.
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Re: MX Exhaust Question

Post by 2manyrides »

The B50 pages @ parkers classics link is below;
http://www.parkersclassics.com/category_s/21.htm
Type muffler in his search box. I contacted him about 9 months ago as it had been a long time. He said, "yes" he was still up and running, but things had been slow. The muffler he had copied is like what was on my tr5mx when I bought it from the triumph shop. They had already removed the one into two set-up. But for me, I did not like it. I had a super trapp and extension done up which has remained on there to this day.

Here's what he had written about the muffler in it's description;

BSA B50 MX muffler megaphone 1971 - 1972
Our Price: $400.00
I have been looking for one of these for over 2 years they are unobtainable
Finally I got one on a 71 B50 MX
I have at great expense had this pipe ( a bit battered) digitally scanned using white light scanning technology.
I was then able to view it in CAD and straighten out the bent bits giving me a full dimension model.
I built a fixture and mandrels , then using the correct gauge tubing created an exact copy.
It has been welded by hand (as originals), A NOS pipe that sold last year for over $420 is indistinguishable and identical.
Pipes are straight through "not for road use" and they sound excellent.
I use on my own restorations refund if not delighted
I must say I have 3 B50 MX and each one is slightly different so may need an "Engineering" tweek when fitted
This is why BSA employed fitters
1973 had a different down pipe bends and different brackets but I also have 1 of these and a TR5MX so i will be making pipes for the 73.
So you can have a nice racing megaphone instead of those large twin chrome pipes.
1008-2T.jpg
1008-2T.jpg (16.13 KiB) Viewed 1128 times
Our Price: $400.00
Availability:: Usually Ships in 2 to 3 Weeks
Product Code: 1008
2many says;
Takes that long to make one?

As well, Though I lost my database this was created from due to a digital failure, this video was made up of a bunch of B50's photos I had saved over the years. Maybe you'll find an idea on one of these bikes..?

[youtube]https://youtu.be/VSnDAJtPaZo[/youtube]

And finally, I say, I have run one of these back in the old days for quite some time with great results... (in my world)
I mean, the bend on the muffler counteracts the bend at the end of the header to give you a perfectly spaced pipe extending past the shock.
But I know, that's not the kind of thing you are looking for. More like the megaphone above. Just thought it was maybe helpful in this thread if anyone else reads it.
1008 2-ts-l1600.jpg
72 B50SS bought in 74, I'm the second owner
74 TR5MX bought in 77-new, I'm the original owner

Which one to ride today?
johnu
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Re: MX Exhaust Question

Post by johnu »

2manyrides wrote: Tue May 05, 2020 10:39 pm The B50 pages @ parkers classics link is below;
http://www.parkersclassics.com/category_s/21.htm
Type muffler in his search box. I contacted him about 9 months ago as it had been a long time. He said, "yes" he was still up and running, but things had been slow. The muffler he had copied is like what was on my tr5mx when I bought it from the triumph shop. They had already removed the one into two set-up. But for me, I did not like it. I had a super trapp and extension done up which has remained on there to this day.

Here's what he had written about the muffler in it's description;

BSA B50 MX muffler megaphone 1971 - 1972
Our Price: $400.00
I have been looking for one of these for over 2 years they are unobtainable
Finally I got one on a 71 B50 MX
I have at great expense had this pipe ( a bit battered) digitally scanned using white light scanning technology.
I was then able to view it in CAD and straighten out the bent bits giving me a full dimension model.
I built a fixture and mandrels , then using the correct gauge tubing created an exact copy.
It has been welded by hand (as originals), A NOS pipe that sold last year for over $420 is indistinguishable and identical.
Pipes are straight through "not for road use" and they sound excellent.
I use on my own restorations refund if not delighted
I must say I have 3 B50 MX and each one is slightly different so may need an "Engineering" tweek when fitted
This is why BSA employed fitters
1973 had a different down pipe bends and different brackets but I also have 1 of these and a TR5MX so i will be making pipes for the 73.
So you can have a nice racing megaphone instead of those large twin chrome pipes.

1008-2T.jpg

Our Price: $400.00
Availability:: Usually Ships in 2 to 3 Weeks
Product Code: 1008
2many says;
Takes that long to make one?

As well, Though I lost my database this was created from due to a digital failure, this video was made up of a bunch of B50's photos I had saved over the years. Maybe you'll find an idea on one of these bikes..?

[youtube]https://youtu.be/VSnDAJtPaZo[/youtube]

And finally, I say, I have run one of these back in the old days for quite some time with great results... (in my world)
I mean, the bend on the muffler counteracts the bend at the end of the header to give you a perfectly spaced pipe extending past the shock.
But I know, that's not the kind of thing you are looking for. More like the megaphone above. Just thought it was maybe helpful in this thread if anyone else reads it.

1008 2-ts-l1600.jpg
I appreciate the help, thanks!
KTM 350sxf
KTM 500exc
BSA A10 Road Rocket (RGS Rep)
TR5mx
S*zuki GT500
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