Exhaust thread repairs

[maylar]

A buddy has stripped exhaust ports on his 72 Combat. He figures that the head should be freshened up too as it's been 15 years or so since it's had any attention. Any recommendations for shops that can do both?

Thanks

 

[swooshdave]

A buddy has stripped exhaust ports on his 72 Combat. He figures that the head should be freshened up too as it's been 15 years or so since it's had any attention. Any recommendations for shops that can do both?

Thanks

CNW?

That Comnoz thread fix looks pretty solid.

 

[mikegray660]

i had Phil at fair spares do mine about a year ago (while redoing the head w/ new seat/valves and ensuring the head was flat) and he did a most excellent job -

that being said i also helped a friend assemble his bike who had Matt at CNW do it on his 750 w/ a rebuild - also very very nice work

 

[rvich]

After reading the thread on thread repair that comnoz posted, that would be my direction.

 

[britbike220]

I bought an aluminum insert from Baxter for mine 8 years ago and had a local machine the head and weld it. It has been as good as new since. I think it's cheaper to have a decent local do work as long as you trust them than sometimes having a "specialist" do the same job for three times as much.

 

[swooshdave]

After reading the thread on thread repair that comnoz posted, that would be my direction.

documentary-exhaust-thread-repair-t4517.html

Here's the thread but the pictures have been moved. I sent Jim a PM so hopefully he can fix them.

In the meantime you can view all the pics here:

http://s658.photobucket.com/albums/uu31 ... /Projects/

 

[rond944]

Leo Goff at Memphis Motorwerks .

 

[ColoCommando]

A buddy has stripped exhaust ports on his 72 Combat. He figures that the head should be freshened up too as it's been 15 years or so since it's had any attention. Any recommendations for shops that can do both?

Thanks

CNW / Jim Comstock redid the threads on my 75 850 - excellent work, highly recommended.

 

[Coco]

CNW did my head rebuild too. Top shelf work.

 

[Rich_j]

Screwed in solid inserts aluminium and bronze, wire thread inserts (helicoils), welded in aluminium inserts - all good, which is best? No idea.

What I can say is that pressed in bronze inserts are a bad idea. My head came with these fitted. One of them came out still attached to the exhaust pipe. The head had cracked around the port. Took a lot of welding to fix, aluminium inserts were welded in at the same time, they've stood up pretty well so far but I must admit the screwed in bronze ones look nice.