Exhausting time ...

The ST flat twin I'm currently restoring has an exhaust. What I'd really like to do is to get it replicated for the other engine. It is an easy job as there are just two curved pipes entering a tubular silencer at each end and a single exit pipe. The one I have could only be described as flimsy & one in stainless and a little stronger would be ideal.

Anyone suggest someone who could make it up to pattern?

Next, a difficult corrosion problem. The tail pipe is secured by a U bolt. I managed to worm it out from under, but the U bolt is stuck fast in the ali bed plate. Of course, I can't beat the end of the screwed bar & neither can I bang the loop, so have heated & soaked repeatedly. Nothing yet .......

Can anyone think of a chemical solution?

Regards,

Kim Siddorn,

Reply to
Kim Siddorn
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A sold called motor cycle man :-)) should know more than others where to get an exhaust made especially if he was making a hot rod or chopper for instance.

Martin P

Reply to
campingstoveman

Ray Fisher's Brit Bits in Christchurch (can't lay my hands on the address just this minute but I think they now have a website) used to get pipes made to measure/pattern. I thinks they were done by Armours.

There's a lot to be said for thicker pipes. I burnt/rusted my way through two sets of cheap pattern pipes on a BSA Road Rocket in quick succession, and then found an old pair which I wire-brushd and matt-blacked and they lasted for years.

Can't you fit a *tall* nut, or even two locked together to get that bit protruding beyond the thread onto the the threaded end, with just a little slack at the bottom, so that you *can* cautiously beat on the threaded ends by hitting the nut rather than the bolt.. Nothing too enthusiastic otherwise the bolt will bell out into the gap and stick even tighter into the ali, but worth a gentle try perhaps. And a large hammer used gently for that nice dead bounce. But you probably know all this anyway ;-)

Gyppo

Reply to
J D Craggs

Bike engineers catering for the classic market tend to be pricey & Armours don't seem keen to do stainless work. I wanted a stainless pipe for the International, but " ... it would be ten weeks at least and be nearly twice as expensive." "Why? It doesn't need plating."

Faf - faff - faff.

I wondered about dairy engineers who are used to stainless.

The U bolt is only 3/16" in diameter (wire thickness) and I'm loath to damage it unless I have to. I'll look out a bigger gas torch ........

Regards,

J. Kim Siddorn,

Reply to
Kim Siddorn

"Kim Siddorn" wrote (snip):-

Some while ago on the Scott OC site it was suggested that head studs could be persuaded to release their mighty grip on the ally head by being brought to red heat with a welding transformer. Bear in mind that I have never tried this and indeed viewed it with a certain amount of scepticism at the time - but what have you got to lose, oh yes, cracking a potentially irreplaceable bed plate. Caveat secuutus!

Reply to
Nick H

One of our customers uses a welding transformer and a carbon piece instead of a rod, the resistance of the carbon makes it heat up to red heat locally. They were soldering cables onto 200A connector pins and didn't want to use a gas torch.

Peter

-- Peter & Rita Forbes Email: snipped-for-privacy@easynet.co.uk Web:

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Reply to
Peter A Forbes

Armours work is expensive and pipes of poor quality.

Contact Maniflow in Salisbury, who will very likely be able to supply good quality mandrel bends in MS or stainless, so you can easily make your own exhaust!

Reply to
Ken

Heating a steel part thats badly corroded into an aluminuim part, will achieve very little.

If you are able to get to the corroded part, then I would suggest cutting it in half, and then gripping with a good mole wrench and attempt to get it turning, then when its loose in the alloy plate cut off the part you are holding and tap the threaded part up through the alloy plate.

k
Reply to
Ken

Kim, give us less educated souls a clue. What diameter pipe are we looking at? SS pipe is now readily available in various wall thicknesses and diameters. Various costs too.

John

Reply to
John

Oh, I never thought to measure it John - certainly no more than 1" ID & I'd judge the entire system is made from 22SWG sheet & tube. The tubular silencer has ali end caps & an 1/8" diameter through bolt to hold them on. The whole thing was built down to the weight of 85lbs including dynamo, so as to be suitable for forward radio positions. The exhaust is not free to move about, so very light sections would do fine on such a device.

Although one might think that a plain steel exhaust might rot through in the

68 years since it left the factory, it is in remarkable condition - but there, it might be a replacement just before it left Service life .......

Regards,

J. Kim Siddorn,

Reply to
Kim Siddorn

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