The trick of filling with water and putting in the freezer

[clmintie]

I've just done this on a KX85 pipe with a dent similar to yours and it worked superbly...

Plastic bag cable tied over big hole (exhaust end) fill with water from muffler end to 75% full and place in deep chest freezer vertically. Check after 4 hours and then every 1/2 hr until dent fixed. DO-NOT leave 'over night'.....

Your mileage may vary, but I'm about to do another, and have no qualms about it...

[B0000M]

i've done this successfully a couple of times too, best for big dents.

the ends do freeze up first- that solves that issue pretty early on

as for the rest keep an eye on it. as above, time it so you can check on it, i have heard of people who have over done it and split their pipes

[gammaguy]

.....does it work along a welded seam?
Attachment 261969

water can t be compressed

but the seal on the item you want to break may be able to

[barty5]

Ive done in the past plugged in take end fill with water place in freezer but a must is plastic bags over end or your freezer will end up with oily black shit all over it. if it dosnt all come out let it thaw out till the ice is able to move around in side refill and re freeze but be very careful this time keep checking i forgot and the 1st one split open at the seams messy.

[Crabby]

did this about 17 years ago to a kdx 200 pipe, only issue I had was explaining to mum why there is an expansion chamber in the freezer, worked mint, I left it overnight and it had popped the dent right out.

[K6K]

results may vary

then I got greedy and put it in for a bit longer to see if I could get the rest of the dents out - 30 minutes later it split at the widest part, slightly to the side of the weld...cant find a pic of the damage.

Now I plug the ends and use compressed air plus a mapp gas torch.

[Crabby]

lol love the shot of it in the freezer.