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I got some christmas money and figured I should fix my Rev pipe. Is there a dependable shop on the east coast? Pacific Crest is a little too far.

try freeze plugging the pipe filled with water then put it in the freezer or outside. works on KTM pipes, but they are god awful thin.

Look this thread over. Sounds like these places are in your neck of the woods:

http://www.ecea.org/forums/index.php?showtopic=13104

the freeze method will work great and save you your christmas money as well.

Fill the pipe with water and plug both ends. Throw it in the freezer over night and then take it out and let it thaw. repeat these steps over 3 or 4 nights depending on how bad the pipe is.

The dents will slowly get removed and you should be able to get it very close to like new.

besides... a few dents in the pipe shows "love".

[quote="xagentman
besides... a few dents in the pipe shows "love". [/quote]

In that case, Onda's pipe has surely had it's share of love!

Ondatrail: Let's freeze it!

2001kdx wrote:[quote="xagentman
besides... a few dents in the pipe shows "love".

In that case, Onda's pipe has surely had it's share of love!

Ondatrail: Let's freeze it![/quote]
Your zuke could use it too man! now to find a big enough freezer

I always thought that in the winter time New York WAS a freezer. Does it get cold enough there to just leave it outside.

jc7622 wrote:I always thought that in the winter time New York WAS a freezer. Does it get cold enough there to just leave it outside.

I can hear the sound of people going Doh! lol

Freezer trick might take out some of the dents but it won't make it fit better

Send it to Pacific Crest and it will fit as good or better than it did when it was new

http://www.piperepair.com

I saw a kid repairing his own pipe on a KX125. He pressurized the pipe using an air pressure regulator to limit how much air he put in there, and then used a torch to heat the outside perimiter of the dent. With low pressure and careful heating he was able to take the dents right out. I'm sure it would leave a mark on a chrome pipe, but a painted one should be no problem.
Joe

Mr. Wibbens wrote:Freezer trick might take out some of the dents but it won't make it fit better

Send it to Pacific Crest and it will fit as good or better than it did when it was new

http://www.piperepair.com

Fits fine.

Not sure if I should freeze or heat but I'm leaning towards heat even if it discolors, not that clean to begin with...

I've performed the heat-to-remove "dent trick" on dozens of dents. It will work!!

The whole freezer approach just does not sound "right" to me!!! I've read about people bursting pipe seams, etc. I've also read about people saying the "key" is the orientation of the pipe when you have it filled with water - in that you want the highpoint where the dent is.

The engineer in me BS - says 'lots of surface area on the pipe cones - how does the water know what to expand? It is just going to expand 10% and apply pressure uniformly once frozen it will move the weak link in the system: Maybe a seam will let go - thinner material in cones: (possibility of removing a dent in a cone does exist if the dent equals 10% of the pipe volume and none of the pipe welds is weak - what are the chances of this?) While the water will start freezing from the upper surface and work its way down to the lower water levels; will not the pressure created by the frozen water expansion still be exerted throughout the pipe by the water which hasn't frozen yet?'

I maybe could see the frozen water method work on 4 stroke header pipes or pipes with a uniform diameter and uniform wall thickness the key would still be to remove the pipe from the freezer prior to bulging or bursting the pipe IMHO.

Now I will say I have not tried this and if asked for advice I would say send it off to PC repair or have an experienced friend or shop blow out the pipe dents for you using the proven method of heat combined with pressure. I expect flames since I've provided the fuel

Seems to me that heating the pipe would be more "predictable". Or how about drilling a hole in the pipe, PULLING the dent out, then welding over? Or drill a hole in the pipe across from the dent to allow access to push the dent out from the inside?

Since the freezer method relies on pressure due to expansion, if you DO try the freezer method make sure you:

1. Fill the pipe COMPLETELY, no airpockets/voids anywhere

2. Seal/plug it off VERY well.

I'm not talkin' from pipe-poppin' experience here, just plain physics. The volume of water that's freezing will expand about 9% (but not after it freezes for what it's worth). While the expansion is occurring where the freezing takes place, the pressure caused by the expansion would be felt throughout the pipe if there is no gas/air to compress and if the water is not escaping from the ends. All of this means:

*The orientation of the pipe is probably NOT a factor if it's going to work.

*The expansion WILL occur: if all of the water freezes in the pipe, it WILL grow by roughly 9%. Once any dents are popped out, either the plugged ends will be relieved or somewhere else in the pipe wall will. On the other hand, if only a portion of the water is permitted to freeze, the expansion will be 9% of that portion. Bottom line is you should keep an eye on it as it's freezing.

All that stated, no flames for IC from me - there's a risk that another part of the pipe is weaker than the dent!!!

It's a gamble. You might be saving yourself $50 or you might be buying a new pipe

Even if the pipe ruptures instead of pushing the dent out, the pipe will still be repairable; just that now there will be the dent and the split from the water freeze. I bet the pipe repair shop won't charge any more than their standard repair rate despite the extent of damage. So this is only a win situation to try or at least nothing lost in the attempt.

Go to the Mieneke Shop on Rt. 300-Newburgh. Danny Z. the owner fixes pipes for a small fee

So, has anybody actually tried the questionable-from-an-engineering standpoint water-freezing method?

I'd be afraid that the water freezing method would expand the entire pipe, not just the bend. Maybe the effect would be too small to make a difference. Anybody have a junk one they want to try it on. Take measurements around the entire pipe and see what happens when you freeze it several times.
Joe

In most cases you could probably just leave it..... I've got a quarter-sized dent right up bu my radiator.... no worth freezing and not worth Pacific Crest either.

OndaTrail is on a completely different baot however, his desert pipe is a $60 ebay pipe I bought because I was low on cash.... It's great for performance, but not for looks.

Why not let one of these guys do it for you. They work dents from the inside on cars, I bet they could do a pipe as well.

Mark W