Can I fix this?

[TJR178]

Hi All,

Below are a couple pics of a section of Arrow exhaust with a healthy dent.  I bought the exhaust like this for a good deal.  You can't see the dent when the pipes are on the bike, but I know its there and it bugs me.  I'm not sure if this is significant enough to harm performance, but I'm guessing it won't help.

I tried the freezing water trick, but that didn't work.  Do any of you have other ideas to pull this dent out?

BTW - I heard these pipes came from you Derby...



Uploaded with ImageShack.us



Uploaded with ImageShack.us

[Punx Clever]

A body shop could probably pull it out a little bit for you, but it wouldn't be perfect. 

[DarkStaR]

Cut the pipe at the weld, use a pipe expander to push the dent out, re-weld.

[loopsrider]

Use an old motocross trick... FREEZE IT!

Fill it with water to about 6" on both sides of the dent. Prop it up in the freezer and let the ice expand the dent out. It useally takes 2-3 freeze/thaw cycles. I've done it quite a few times and it works well. Here's the latest dent repair on my KTM 505 SX-F...

Before...


1st freeze....


2nd freeze...


Final Freeze...

[loopsrider]

My girlfriend is the coolest... She let's me get away with stuff like this...




She rides too so she understands.

[booger]

damn loops, you got that method down don't you

[scduc]

I must say that that is impressive. What I dont understand is how come the freezing action doesn't just expand through the tube. You would think that you would have to plug it to force the ice to stay at the dent.

[loopsrider]

I must say that that is impressive. What I dont understand is how come the freezing action doesn't just expand through the tube. You would think that you would have to plug it to force the ice to stay at the dent.

It seems the water freezes from the ends inward so it kinda plugs itself off, then expands.

I just noticed the original poster mentioned he has tried the freezer method. I've found it sometimes takes quite a few freeze and thaw cycles with varying water levels to start to move the dent. After it gets moving it usually comes out (for the most part) in the next freeze cycle. I've had dents that have taken 4-5 cycles and barely have moved on the first cycle...

Wonder how many times he has froze it


disclaimer: don't fill the pipe completely full of water... I have bulged pipes doing that. 6" of water on each side of the dent usually seems to work well...

[zarn02]

First you need to find some tiny hammers.

And to work these hammers, you need to find a team of very small men.

Now, you'll have to pay union wages, but they're good workers. Get them, and send them into the pipe. It'll be a day or two, but they'll have that hammered out just how you want it.

(I was going to post this earlier, but decided to wait until people with actual advice had chimed in...)

[hadesducati848]

First you need to find some tiny hammers.

And to work these hammers, you need to find a team of very small men.

Now, you'll have to pay union wages, but they're good workers. Get them, and send them into the pipe. It'll be a day or two, but they'll have that hammered out just how you want it.

(I was going to post this earlier, but decided to wait until people with actual advice had chimed in...)

i found that smurfs work really well, the 7 dwarfs a good also but a bit big, the littles are hard to find but worth it if you can. just stay away form the keebler elves all they do is stand around and eat cookies. 

hahha

but on a side note the freezing water is a cool idea, i want to dent a pipe just so i can try it.

[He Man]

I must say that that is impressive. What I dont understand is how come the freezing action doesn't just expand through the tube. You would think that you would have to plug it to force the ice to stay at the dent.

Do you ever wonder why the top of a lake freezes first and not inside out?

[scduc]

Do you ever wonder why the top of a lake freezes first and not inside out?

Now that you put it that way, it does makes sense, but you would still think that the pressure would move in the direction with least resistance.

[TJR178]

Looks like I need to try and freeze it a couple more times loops.  I only froze it once, so hopefully it'll work the next couple times.

I've did this on a MXer a while ago and the dent came out, but blew a weld too.  Different steal I think though.  I'll try this again.

Thanks for everyone's help!

[TJR178]

Update:

I froze the pipe twice since my last post and it's starting to push out more.  This is one hell of a dent, so it may take a few more freezes.

[DucHead]