Pipe Repair

[arpenn]

I dented my fmf fatty pipe and would like to learn to fix it my self. I am having trouble finding any information on pipe repair. I hate to spend $40.00 plus $24.00 shipping every time I dent my pipe. Has anyone ordered the "Do it yourself motorcycle exhaust pipe repair" guide from Exhaust Works/HighVelocityGear? They want $10.00 for the guide which I don't mind paying if it explains the process well.

http://pipeworks.homestead.com/exhaustworks.html

Thanks

 

[cobraR]

yes i would really like to know this to, i have a pretty good size dent in my fmf fatty pipe too. i know you can send it out for 40.00 and s/h

 

[FritoBandito]

After I dented my pipe and got it repaired, I invested in the carbon fiber pipe gaurd. It is a cool looking add on and it works.

 

[freeridin04]

i've never tried this but i've heard it works. fill your pipe with water and plug the ends very tightly and then put it in the freezer. but you gotta be careful or it can break the metal. so jus keep an eye on it

 

[dklink2000]

The freezing trick is a really good way to split your pipe. Where is the dent and how deep is it. I have read that as long as it is not within the first 6 in, and is not deep enough to restrict flow, that it has no effect on performance.

 

[arpenn]

I really don't want to try the freezer too unpredictable. I want to learn how to remove the dents the way the professionals do. I'm a shop teacher so I think I can handle it. I just want to learn the correct way so I don't destroy my $200.00 pipe or kill myself. The dent is in the large part of the pipe and is probably 1-2 inches deep and 3 x 4 inches in diameter. Its not a simple dent part is deeper than the other and there is a crease or close to it. I just wondered if anyone did this type of repairs themselves or if anyone had purchased the literature from the web site I listed in my original post. Thanks for the responses, I hope someone here might be able to help.

Thanks,
Aaron

 

[Psalm31.24]

go to proride.com forums. search "getting rid of pipe dents"

 

[Eggnchips]

I made a couple of pipe clamps, each one consists of a car exhaust U clamp, a piece of 2mm thick steel plate and 4 hooks with an old inner tube cut up to seal the joint and provide a schrader valve for inflation. You fit one on either end of the pipe, inflate to 50psi and heat the dent with a gas torch. The dent comes out very slowly, but works a treat.

 

[Studboy]

Originally posted by Eggnchips
...but works a treat.

Until one of the plugs blow off, or the area you are torching blows through spewing hot gas all over you! :eek:

 

 

[TM-Frank]

Originally posted by Studboy
....Until one of the plugs blow off...

Yes, that is a bit delicate :) You should make sure that you don't point at other people, your dog or anything that might be expensive.
If you use some kind of squeeze plugs make sure that you remove coal and oil residue from the inside of the pipe's end before installing the plug.
Additional safety wiring is a good idea, too! You can make a safety-catch-line out of stell cable (old clutch cable or so) and a good hose clamp. Attach one end of the cable to your plug and the other to the pipe.

Originally posted by Studboy
....or the area you are torching blows through spewing hot gas all over you! ...

That is unlikely when you use a propane torch but can easily happen when you use a acetylen/oxygen setup. The propane torch isn't hot enough to melt the steel. But it is surely recommendable not to place yourself directly in front of the heated area.
Japanese stock pipes should be handled with special care! The welding seams are often so ratty that they can crack! So use lesser pressure with these pipes. MESSICO, SPES, HGS (and propably most other aftermarket pipes) can put away really high pressure.

 

 

[slickpuss]

I plug one side with a rubber plug and the other side with a rubber plug with a hose ran through it. I use about 30lbs of nitrogen and heat the dented area with a map gas torch. It works great. But I wouldnt do it if I didnt have access to inert gasses.

 

[qwchrbeliakn]

I took my pipe a few years ago to a shop and watched 'em fix my dents. If I remember correctly, expandable rubber freezeplugs were put in each end of the pipe, the pipe was pressurized (with air) to 50 psi, then the dented area was heated with an oxyacetylene torch. I think the 50 psi is necessary (as opposed to heating up the entire pipe to increase presure) so that the heat can be concentrated on the dent, the dent popped out, and heat removed as quickly as possible. If you wait 'till the pipe pressure increases from the heat source alone, the pressure could rise very quickly and exceed well beyond 50 psi and blow the ends off...although these kind of events do make for good stories.

I tried this procedure a few months back on my budies Suzuki pipe. Darn dent wouldn't budge because all I had was a MAP gas torch and couldn't get enough heat on it. I don't have an oxyacetylene torch at the moment. I think I'm gonna give it another shot with two MAP gas torches going on the dent at the same time. That should take care of it. Be careful.

 

[TM-Frank]

I use air, too, but add a (real small) gulp of water. My starting pressure is usually around 40 psi. Then I start with holding the pipe so that I can boil the water with the torch. I have noticed that the steam pressure somehow seems to be some kind of stronger than dry air. You need less heat and less pressure, but I cannot really explain why ;)
I never tried the oxygene/acetylene thing, because a) I don't have one and b) are much too frightened :) It always worked fine with the propane torch, it just takes a while when you have a fist-sized dent.
I think slickpuss uses inert gas to avoid that the 21% oxygen in the air form a combustible mix with the oil/fuel residues in the pipe, right? Surely nice to have, but I repaired a lot of pipes in the last three years with air pressure and haven't blown myself up yet.
(Maybe I should try to learn how to ride the bloody bike some day so that I don't crash that often.)
The procedure is definetly dangerous and I wouldn't trust a twelve year old with it, but it is not suicidal or so. Provided you use your brain first and take some protective measurments.

 

[dklink2000]

If you are not getting enough heat with MAPP gass you can try one of those MApp/O2 setups. I have been looking at getting one, anyone have any luck with them?

 

[whyzee]

My plumbers use a heavy gauge test ball that is inserted into PVC pipe and pumped up with air (used for holding large volumes of water in place during the plumbing rough-in inspection). These test balls (not really a ball but more of a cylinder shape) come in different diameters and could be inserted into the pipe and expanded to pop a dent out. Need to remember to remove the valve so it will deflate once pressure is removed. The trick is to find the fittings to go from 1/2" sae pipe thread to what ever an inner tube thread is... Then all one would have to do is feed it into the pipe and turn on the air from the compressor. Dent should pop out w/o heat ... no?

 

[Eggnchips]

It's a MAPP gas / O2 setup that I have and it's just about as hot as oxy accetylene.

 

[Eggnchips]

Studboy, they are not plugs they are clamps!

Like any kind of engineering task there is risks involved, as long as you understand what your doing and take appropriate safety measures , then it is no more dangerous than sctratching your balls!

However I thank you for your concern of my health.

 

[arpenn]

Guy's Thanks for all the information. Does anyone know anyone that has purchased the Do it yourself dent removal instructions?

Aaron

 

[KrackerRacin]

here it is explained at this site.

http://www.allthingsmoto.com/forums/showthread.php?s=&threadid=789