Pinholes in exhaust downpipe -- best way to fix?

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Craig380
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Pinholes in exhaust downpipe -- best way to fix?

Post by Craig380 »

My set of vintage expansion chambers decided to develop a couple of small pin-holes in one of the downpipes this weekend, I thought a V1 flying bomb was going overhead :oops:

The two holes are both less than 2mm in diameter, and the metal immediately surrounding the holes is solid (it does not yield to a good poke with a screwdriver).

What do you guys think is the best fix -- braze up the holes, or just stick a couple of blobs of weld on?

The pipes are painted black to conceal rust-pitting, etc, so cosmetic appearance does not matter.
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djfisher22
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Post by djfisher22 »

I'd braze em up. Easy peasy. 8)
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H2RICK
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Post by H2RICK »

I'd braze 'em too.....but rather than brass, I'd use high temp silver braze rod. More durable and less prone to cracking and resists chemical attack far better than brass/bronze. The trick is to find someone who can gas-weld AND
understands light gauge metal welding....:cry:
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Craig380
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Post by Craig380 »

thanks for the tips, guys.

As it happens, the metal around the pinholes was a bit too thin to take a proper repair, so the welder ground out the bad stuff (about a 2" x 1" hole), made up a neat little patch, welded it in, then did a nice job of smoothing the welds. A quick coat of fresh satin black and you don't notice it from 3 feet away. All for $25.

It's good to have easy access to skills like that.
1976 GT380 - wounded by me, and sold on
2006 SV650S - killed by a patch of diesel and a kerb in Feb 2019
2017 SV650 AL7 - naked and unashamed
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