Fixing a dented header for cheap!


JohnnyAirtime

Anyone a skeptic??? I sure was, until last night. Here's what I did, and to what:

I dented my FMF Ti header pre-running for the Baja 500 recently. Sure it wasn't too bad, but bad enough where people see it and say "hey... your pipes dented..." Enough to make you want to fix it right?!

After reading on several forums about filling the pipe with water and putting it in the freezer to pop out the dent, I was pretty skeptical. I thought, "how can freezing water be that powerful?" Also, not being any kind of engineer or scientist, I had to try it!

Skeptic? Yes. That is until I actually did it last night and found it to be 100% true! Simply amazing and so easy! Here's just how easy it was:

- Took the header off in about 5 minutes (from CRF450X).

- Added enough water to fill the dented area of the pipe, plus a bit more

(did not end cap the pipe or plug anything).

- Placed in freezer so that the pipe wouldn't leak any water.

- Woke this a.m. to a near perfect repair!

This repair sure saves taking the pipe to a welder (which I am by hobby) and having them use a rosebud and air to blow out the dent!! Plus, this is MUCH cheaper. You may need to attempt this two, three or four times to get the dent completely removed. But don't give up, the reward is worth it.

Good luck!! And have fun!

An edition to this article by sootgrinder

In the tech tips section there is a nice write up on how to use the freezer to pop out dents in your exhaust header pipe. It is a nice article, and the process works well for four stroke pipes that are a consistent diameter, I.E. not stepped headers or Powerbomb type headers. But it would be nice is you could put some language at the end of the article to warn against using this tip on stepped headers and definately not two stroke expansion chambers. I have personally seen expansion chambers ripped apart at the welds when trying to use the freeze technique. I just want to prevent someone from ruining an exhaust system, and getting upset because they thought it would work for expansion chamber pipes as well.




User Feedback


i did it with my expansion chamber and yes ! it did split it an not even at the weld it split a 6in. crack down the middle little over an inch from the weld heads up do not try this with an expansion chamber ! lol

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I wonder if this would work in an expansion chamber if you used less water? The key would be to add just enough so that when it expanded it would just fill out the original pipe. One problem is that the dent material will likely be harder than the rest of the pipe due to work hardening. To fix this, you could anneal the pipe by heating it up just below cherry red, then cooling it very slowly. Easy to do by burying it in a nice bed of hot campfire coals and just leaving it there to cool as the coals die out, say overnight. Just a thought.

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