[CR] Exhaust pipe help?

[DarkFox]

I don't remember if i posted about this before.. anyways .. :
When i was learning to ride my CR about 5 months ago, i ran it into a small tree stump. NICE squash in the pipe as seen ( HERE ) and ( HERE ) Would a dent such as this cause problems for the engine? I just finished some other problems with it (tires, tubes, chain, sprockets, plastics, air filter) and I would like to get this taken care of eventually, but is it OK to ride it with the pipe in this condition??

 

[biglou]

It won't hurt anything but possibly your power.

 

[bikepilot]

It could actually hurt the engine. The exhaust is primarly responsible for cylinder scavaging and loading. Damaged exhaust could theoretically cause increased egt's to the point that you suffer detonation and piston erosion. Very unlikely but possible. Personally, I would ride it like that if the only other alternative was not riding. I would pick up a stock pipe on egay and a carbon fiber pipe guard from e-line asap. The damage pipe will hurt the power output without a doubt.

good luck

 

[triden]

I was reading an article in one of the dirtbike magazines (forget which one) and they did a bunch of dyno tests on dented exhausts. The results they came up with is that you wont suffer any power loss of the dent is passed the fist 10 inches of the exhaust port.

If you want to fix it, pressureize the exhaust with a couple pounds of air - make sure its off the bike. Then with a torch, slowly heat up the dent and the air should push it back out to like it was

 

[DarkFox]

I know about the pressure trick, but how do i go about capping the ends of the pipe and pressurizing the pipe? I've noticed that from the time I did that to the pipe, it had a significant loss in power. I don't want to go out and buy the stock OEM pipe, because when I bought this bike, it came with this Pro Circuit pipe on it, and I don't want to just toss a $205+ dollar part.. you know ? :think:
I got some of its power back unearthing the air filter (it was literally caked over) but PLEASE tell me what to use to pressurize that pipe! Its driving me nuts and I want to ride it soon :bang: :bang: :bang:

Oh, and I apologize to the moderators for the double thread post. I posted the thread at school, where both the download and upload speed are locked at 'suck'.

 

[tyesai]

You could try this. Looks a little labor intensive, but there is no pressurizing the pipe.

http://www.off-road.com/dirtbike/tech/pipefix/

 

[The_STiLe]

if you are still going to school i wouldnt recomend trying to heat the pipe yourself.
im sure a bike shop will fix it for a reasonable price.

 

[Colorado]

You can also use a body repair slide hammer and heat. On small dents drill a hole in the center, heat the surrounding, creased part with a torch, then use repeated, moderate 'hammers' with the slide while moving the torch heat around as needed. On bigger dents it might take more than one hole. You don't have to get the shape perfect. Just stop any flow restriction. Weld or braze the holes closed when you're done. My IT400 Clymers suggested this and it worked very well.