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2T Pipe Repair

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_RG_

_RG_

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Here's an opportunity...

My stock KTM pipe had collected its share of dings. They say two stroke pipes are consumable items like tires. But, it's also rumored that some of us prefer to save $$$.

Removing dents from these things is an art and science. This was my first experience with it and the results turned out way better than expected. One dent was right on a welded seem. No problem.

I need some more dented pipes to practice on. Here's a deal...first five folks to send me their dented pipes will get their pipes repaired at no cost beyond shipping. Here's your chance to drag out that old beat up pipe hanging in the corner of your shop and give it new life...ship it to me and save a couple hundred bucks on a new pipe in the process. PM me here for shipping info.

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I still haven't seen your 2 stroke. Maybe Sunday ? (Goertz ranch)
 
What is your repair process? Shoot me a PM if you want, with the address. I have a few dents in my FMF pipe I want fixed.
 
Goertz has been on my list, Vinny. Bad timing though for this weekend. :doh:

The pipe repair process is essentially an internal over-pressure approach.

My pipe had a dent near the head area (pictured). The engine ran different immediately when it happened - started blubbering. I've wondered why two stroke pipes have such weird shapes. Seems they create reverberating pressure waves that pack the fuel charge from the pipe back into the cylinder. Kind of a super-charging process. Look up "wet oil line" tuning and you can get the full story on this. It's a pro technique for maximizing HP.

The real magic takes place within that first few inches of the pipe. This is an area where any disruption in the flow is going to have bad results on engine performance. After repairing the pipe - bike rips smooth from idle straight up. Amazing difference :thumb:
 
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The belly is more important than those first inches. In the beginning the pipes were basically the same diameter all the way. When they discovered the ability to tune with the bulge, the magic was born.
 
There had to be some interesting discussions around the campfire developing the things. I think it was dirt bike mag that did a test on them last year comparing stock pipes against the usual suspects. One of the pipes took a good lick and came home with a respectable dent right down in the bulge. They put it back on the dyno and the bike had gained more HP than it had when the pipe was pristine. Go figure... :ponder:
 
McGrath used to fill his dented pjpes with water, plug the ends and shove em in the freezer. Never tried it, always thought it was a need idea

Winterizing is wearing a jacket!
"It's Always Riding Season!"
 
I was looking for the 2T Pipe Repair sign to be somewhere on the road through Mumford yesterday.

Didn't see it.

Waved in your general direction anyway. :rider:
 
MotoTex, you shoulda wheeled in while in the neighborhood. Had a cold brewski out on the porch and then got put to work out in the shop building stuff. Drop by anytime. :trust:

I've heard the freezing water story. Just still wondering how water can tell the difference between a dent and a weld seam. In the interest of science... I'll put a dent in a Coors can, fill it with water and then screw the lid on really tight - and chunk it in the freezer. Guess you just keep filling and freezing till the dent disappears or a crack happens?
 
_RG_ said:
MotoTex, you shoulda wheeled in while in the neighborhood. Had a cold brewski out on the porch and then got put to work out in the shop building stuff. Drop by anytime. :trust:
Click to expand...

Would have had we not been headed to see MCB's grandkids. Mission priorities and all, hope to next time.
 
Recently took advantage of RG's offer and sent a FMF Fatty pipe that had more than its share of dents in the diverging cone and mid-section. Healthy dents. Deep dents. Got it back today, can't believe how well it turned out. Thanks, R.G., well done!
 
Glad to have helped. That thicker material takes a little different approach than stock (KTM) pipes but is also more forgiving. I'm coming to believe that unless a pipe is twisted into a square knot, fixing sure seems to make more sense than replacement. $$$
 
You still needing Pipes to work on? I tried doing mine myself with heat and air pressure...no luck:doh:
 
Small drill and a slide hammer from Harbor Freight makes fixing easy. Quick and cheap also. Many times you don't even need to take the pipe off the bike. Tiny dab of JB Weld and you are ripping again.
 
I remembered a time when I took a hard hit and dented my pipe on the KTM....

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I tried repairing it via the water technique....ie,
filled the pipe w/ water and then capped the ends off w/ some expanding plugs in the plumbing section at Lowe's
and then put the pipe inside the freezer overnight.

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Woke up the next morning, peeked inside the freezer....

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Dent got pushed back out.
I was amazed that it worked.
 

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Dao I have heard the freezing water thing as well. I was scared away from it because I have heard of it splitting at the seams of the pipe.:eek2:
 
yea, I won't lie...that was all I thought about while it was freezing away. I definitely didn't get a good night sleep...haven't tried to pop another dent out since then.
 
So the kit the guy uses in the video looks really nice. Wish I had a drill press to do this. Some higher tech machines would be nice to have everything cut and drilled, but I think with some basic tools you could make it pretty easily.

[ame="https://www.youtube.com/watch?v=2XpEhDAmleo"]Motorbike exhaust dent removal - YouTube[/ame]
 
To me, the dent is like a small crack in your car windshield. Annoying, and you'd like to fix it, but so long as it's there, you won't get another one. Fix/replace it, and the next time you go out you'll just get another one. :D Murphy likes to kick my butt like that.
 
He has the principle but his technique is a bit crude. But, if he's happy with the results then all is well.
 
_RG_ said:
He has the principle but his technique is a bit crude. But, if he's happy with the results then all is well.
Click to expand...

Yeah, I just like his clamp set -up. The one I made sucks. Got about 1/3 of my large dent out, but couldn't get any more. I couldn't get a large enough area hot enough with my little propane torch. Or the Shrader valve or cap would pop off.
 
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