Exhaust port threads

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worntorn

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I'm looking for a quick and possibly dirty way to hold the exhaust nut in place with ruined threads. I plan a major tear down next winter, so the head will be off then for a proper repair. I have tried putting the nut in with JB weld, that failed. Isuspect I may as well pull the head now and get on with it.

A friend made up a tap for the same problem on Vincent exhaust ports. This tap cuts new larger dia. threads into the port right in place, only the exhaust pipe has to come off. He then uses matching larger dia. exhaust nuts which he made up in a batch of 10 or so.
I used the setup on my Vincent and the repair is good enough to be permanent.
Of course he has some tool and die making skills I may be lacking.

On that subject, here is something he built for fun in his basement, one perfect piece at a time. It is the only one in the world, AJS built three in 1934 but all have dissappeared.

http://www.craig.howell.net/legend07/index2.htm

Go to index 36, the bike he built entirely from scratch is the 1934 V4 double overhead cam AJS. Didn't take long either, about 18 months.

Glen
 
Thanks for the link Coco
The stripped port already has had a steel insert welded in, but I see Colorado Norton Works may be able to do their repair in spite of this.

I like the look of the Norivns in particular, some of the Eglis look a bit like Uglis to me.
I have been lusting after a Norivn for some time now, but I am rethinking that after following a recent discussion on the Vincent site. A number of people there own or have owned Norvins. The consensus is that putting the Vincent engine into the Featherbed frame screws up the great handling of the Featherbed. This is because of the high centre of gravity created by shoehorning the large Vincent engine in.
One owner said that he rarely rode his Norvin because of the poor handling, instead chosing to ride his standard Vincent which has a low centre of gravity and handles nicely.
The Eglis are said to handle well though.

If I had the money, I would go for one of the new Godet Eglis, they are a recreation of the Vincent Engined Eglis built by Fritz Egli back in the 70s.
To me they are the most beautiful bike built today, and at up to 1330 CC and just 385 pounds they are fast.

http://www.godet-motorcycles.com/egli/egli03.htm
 
worntorn said:
If I had the money, I would go for one of the new Godet Eglis, they are a recreation of the Vincent Engined Eglis built by Fritz Egli back in the 70s.
To me they are the most beautiful bike built today, and at up to 1330 CC and just 385 pounds they are fast.

http://www.godet-motorcycles.com/egli/egli03.htm

There was a write up in Classic Bike a while back and they had the new Egli-Vincents (not the Godet version) with a price tag of around 40,000 pounds which is roughly $88,400 Canadian :shock: . I forget who the maker was.

They are beautiful machines.
 
Worntorn,
If the port has a steel insert fitted it can't be welded in, and even if its an alloy insert welded you might be able to remove and replace it insitu.
Cash
 
The funny thing is, it is steel and it is welded. Not sure how that was accomplished but you can see the uneven line between the alloy weld and the steel insert quite clearly.
 
Hmmm! I would have thought welding aluminium alloy to steel was impossilble.

Cash
 
cash said:
Hmmm! I would have thought welding aluminium alloy to steel was impossilble.

Cash

Pistons can do it :D (or doesn't friction count ?)
 
I had thought this impossible too. Here is an ad from a welding company called "Muggyweld"
" Alloy 1 is a multi-metal, low temperature solder with a melting point of 350o. Its unique properties allow you to join copper, aluminum, brass, pot metal, white metal, zinc die cast, stainless, galvanized, pewter and steel in any combination. This rod allows you to join metals such as steel to aluminum, which welding instructors are STILL teaching can't be done."

If that is 350centigrade then this product would work for the job.
Perhaps this is the stuff used on my bike.
 
Soldering is not the same as welding, I would reckon your welding instructors are quite correct.
Any way, the insert might be removeable with a bit of luck.
Cash
 
There is a company in Western Washington that does what is called "Explosion Welding" of steel to aluminium. The bike came from Western Washington, so that may explain it.
Anyway, the steel threads stripped out just the same as alloy ones do, so there appears to be no advantage to having the steel insert.
The other exhaust port has no insert and it's alloy threads are in fine shape.
The stripped insert is my fault, several times the exhaust nut came loose while out on rides and the engine vibrations acting on a loose nut destroyed the threads.
I didn't find out about the use/existence of the little lockrings until it the damage was already done.
 
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