Dents in headers and VHT Flameproof paint

[scfire]

Due to a misfortunate meeting with my header and a sharp edge on my motorcycle trailer I now have a hole to fix (red arrow). Going to take the chance to repaint while I have it off. Question is would it be a good idea to take it to a muffler shop to get the dents (yellow arrow) fixed or is it really hurting anything but aesthetics? The dents are less than half the diameter deep and have been there since I bought it. As far as painting goes, has anyone used VHT and cured it on the bike with good results? Not sure the whole pipe including the muffler will get hot enough to fully cure it.

 

[1sttimer]

I've used VHT wrinkle black with good results. It takes about a week to fully harden, even after baking when touch-dry. Overall, great paint. I'd imagine the dents are hurting a minuscule amount if any. I'm sure there are more experts on that on the forum but I can attest to the paint

 

[onefourx]

Ok... dont take it to a muffler shop. Fill with water, freeze, repeat until straight as desired.
Dents will cause turbulence in the flow where it is not desired, but most people wouldnt notice it as most aftermarket headers arent sized properly for the cam/compression/rev range.
As far as the paint, not sure on the brand I use, but it is labeled as a header paint. I spray a coat or 2 on the header before I install, get it on, fire up the bike. While its running I touch up the messed up areas from installing a couple of times, and usually good to go with a long lasting paint. Muffler will get hot enough, go for a ride shortly after its sprayed.

May not be the "book" way of doing it, but I've had good luck.

 

[hillsy]

Fill with water, freeze, repeat until straight as desired.

If you live in a region that has riding seasons, this sounds like a neat winter project

I've used the flame proof paints before and cured them with a butane torch. You need good ventilation though.

 

[scfire]

I've used the flame proof paints before and cured them with a butane torch. You need good ventilation though.

got any tips for the torch trick?

 

[hillsy]

Use a butane torch (it has a reasonably low heat flame) and keep moving the the torch over the pipes (don't sit it in one spot). Keep the flame a few inches away from the paint to start with, then as the paint starts to cure you can move it closer (it's kinda a "feel" thing).

Also, shoot the torch inside the header and muffler ends (this is a less aggressive way of curing).

And make sure you do it outside or where there's good ventilation because the fumes that come off the flame proof paints as they cure are pretty nasty.

 

[bradj]

Plug all 5 ends and put a tire valve in one of the plugs heat dent red and introduce a few psi of air with a compressed or a good tire pump. The air pressure will push the dent out. If you don't fix that big one you should replace the hole pipe. That dent will affect jetting

 

[speedfourjoe]

One way I've seen to fix exhaust dents is to drill a small hole on the other side, and then tap/push the dent out from the inside using some steel rod, then weld up the hole.