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Author Topic: Fixing exhaust dents CB750  (Read 666 times)

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Offline jebon

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Fixing exhaust dents CB750
« on: May 15, 2021, 06:44:55 AM »
Has anyone tried fixing exhaust dents using compressed air and a blow torch?

I have a few dents in my HM300 exhaust that I'm hoping to be able to fix.

But if I end up with a big blemish and a dent that doesn't come out, then I'm not sure I want to get into it
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Offline kerryb

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Re: Fixing exhaust dents CB750
« Reply #1 on: May 15, 2021, 07:05:19 AM »
I like the concept, but I would be surprised if a mere mortal like us could control the heat and pressure well enough to have success.
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Offline Alan F.

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Re: Fixing exhaust dents CB750
« Reply #2 on: May 15, 2021, 07:12:01 AM »
There are some YouTube videos of repairs like this being performed on expansion chambers for dirt bikes, I'll have a look. Hold my coffee....
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Offline RAFster122s

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Re: Fixing exhaust dents CB750
« Reply #3 on: May 15, 2021, 08:00:36 AM »
Highly unlikely to work given the thickness of the steel. Just my opinion.
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Offline bryanj

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Re: Fixing exhaust dents CB750
« Reply #4 on: May 15, 2021, 08:17:58 AM »
By the tiime its warm enough to move its red hot and the chrome is furkled
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Offline Alan F.

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Re: Fixing exhaust dents CB750
« Reply #5 on: May 15, 2021, 08:42:49 AM »
All of the videos I found are repairs to single wall dirtbike pipes that are not chromed. Aren't most Honda chrome pipes double wall? Meaning there is the outer chrome head pipe but inside that there is thinner exhaust tubing, this helps reduce heat to the outer chrome pipe to keep the chrome from turning blue.

Not all dents in the outer chrome pipe will even touch the inner pipe and reduce exhaust flow.

There's always this method from Terry in Australia, look at reply# 508

http://forums.sohc4.net/index.php/topic,177220.msg2089579.html#msg2089579
« Last Edit: May 15, 2021, 08:45:50 AM by Alan F. »
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Offline 69cb750

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Re: Fixing exhaust dents CB750
« Reply #6 on: May 15, 2021, 08:56:24 AM »
Quote
Has anyone tried fixing exhaust dents using compressed air and a blow torch?
Will not work.

Dolly and bending pipe is viable.
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Offline 754

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Re: Fixing exhaust dents CB750
« Reply #7 on: May 15, 2021, 09:00:32 AM »
Got to get inside it and do it cold.. personally I think practising on a good 400 buck donor, is the wrong way to learn this skill.
 Where is tge dent BTW...got a pic ?
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Offline jebon

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Re: Fixing exhaust dents CB750
« Reply #8 on: May 15, 2021, 03:48:04 PM »
Quote from: 754 on May 15, 2021, 09:00:32 AM
Got to get inside it and do it cold.. personally I think practising on a good 400 buck donor, is the wrong way to learn this skill.
 Where is tge dent BTW...got a pic ?
They're small - I just thought if it was possible...
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Offline Alan F.

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Re: Fixing exhaust dents CB750
« Reply #9 on: May 15, 2021, 03:57:59 PM »
Ok, muffler dents, I was thinking head pipe dents. Have a look at painless dent repair videos.
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Offline madmtnmotors

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Re: Fixing exhaust dents CB750
« Reply #10 on: May 16, 2021, 05:38:53 PM »
Those are badges of honor!  8)

Actually they are not that bad. I'd be happy with a set of stock pipes in that condition.  :)
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