Exhaust dent removal

straygator · Post by **straygator** » Sun Feb 26, 2006 11:35 am

I'd like to remove 6"-8" flat dents in the 2 bottom pipes of my '87 FZR1K's Yoshi . If that's possible I'd than want to remove the rust and maybe cermic coat them. Can't believe I'm the only one with this problem, so thanks for any and all suggestions.

Post by **FZRDude** » Sun Feb 26, 2006 12:00 pm

Greetings straygator!!!

to the Hood!!!

I had this problem on my FZ750. I just bought another bike instead.

I'm sure that it could be done, but would require removing the headers, and then cutting the dented sections out and either replacing them or heating them up and trying to ram a slightly smaller diameter rod down and re-expand the pipes. Both options seem to me to be a little extreme. I'd just try to find another headpipe.

straygator · Post by **straygator** » Sun Feb 26, 2006 12:37 pm

I've already bought a Kerker 4-2-1 in stainless, but it looks like it would be REAL loud. And I can't imagine the bike running any better than it does with the Yoshi. I've heard all sorts of fixes like fill it with water and let it freeze, ram ever increasing diameter steel ball thru till roundness returns ... both beyond my inclinations. Guess I try the Kerker and stare at the Yoshi for inspiration. My Kerker is dull and stained, any suggestions to make it look new again. I'm guessing the carbs will need attention too, huh?

dragracer1951 · Post by **dragracer1951** » Sun Feb 26, 2006 12:55 pm

If fixin em was easy, everybody'd be doin it.....
Cut out the dented section and weld in new tube

Outlaw · Post by **Outlaw** » Sun Feb 26, 2006 2:07 pm

I have the Kerker on my bike with a Supertrapp. Its Loud, but I don't think the header is the reason. If I take out most of the baffles it quiets down quite a bit, still not stock sounding, but it's a lot more tolerable. Previous owner was running it wide open (no baffles) it was SUPER loud then. As far as it being stained and dull, it's mostly covered by the fairings anyway. I don't know of a way to clean it up to look new again. (if you use something too abrasive, I think it ruins the quality of the stainless and then it might start to rust)

dragracer1951 · Post by **dragracer1951** » Sun Feb 26, 2006 2:41 pm

if it's stainless....it won't rust

straygator · Post by **straygator** » Sun Feb 26, 2006 2:43 pm

Hi Outlaw
What kind of power you get with the Kerker? Mine has a tiny 8" Kerker can and looks like back pressure will drop. I drive w/o lowers so it won't be hidden. I'll try something a parts store can recommend or go to a marine dealer (plenty here in S.FL)

straygator · Post by **straygator** » Sun Feb 26, 2006 3:00 pm

Hi Dragracer, hope you might comment on the difference between the 4-1 Yoshi and the 4-2-1 Kerker/little can. I read long ago that the 4-1 was better on the top.

Outlaw · Post by **Outlaw** » Sun Feb 26, 2006 3:37 pm

I really dont have anything to compare to with mine. It was on the bike when I got it. Plus the bike wasn't running right. Although, at one point I took the bike out for a test ride and it pulled REALLY hard. I'm in the final stages of the repair, but it's too cold around here to ride very much right now.

I think the results you get will depend on the muffler most of all. Even if you had the same muffler I do, you could get different results. Supertrapps are adjustable, more baffles equals less backpressure and visa versa. Nice thing about stainless is, you don't have to worry about rust.

If you have any success cleaning up that header, I'd like to hear how you did it. Would like to clean mine as well, but I'm afraid of doing more harm than good.

Dragracer: I had a stainless steel hasp on my shed that got paint on it, I tried to clean it off with sandpaper. Bad move on my part, now the hasp is rusting and will have to be replaced. Probably just a cheap part, but that's why I'm concerned about stainless and abrasives.

dragracer1951 · Post by **dragracer1951** » Sun Feb 26, 2006 3:48 pm

stainless does not rust. if the hasp you had rusted...then you got sold a bill of goods....stainless does not rust.
There are certainly many types of stainless but most of them are non corrosive because of the nickel in it...

trailer rails · Post by **trailer rails** » Sun Feb 26, 2006 6:21 pm

Piperepair.com

I use them for my dirtbike. They are cheep and do great work.

straygator · Post by **straygator** » Sun Feb 26, 2006 10:44 pm

Thanks Trailer Rails, that's just what I've been looking for.

DAVE · Post by **DAVE** » Mon Feb 27, 2006 1:19 am

straygator wrote:I'd like to remove 6"-8" flat dents in the 2 bottom pipes of my '87 FZR1K's Yoshi . If that's possible I'd than want to remove the rust and maybe cermic coat them. Can't believe I'm the only one with this problem, so thanks for any and all suggestions.

There is a bloke I work with who removes dents from dirtbike expansion chambers. His technique is to seal up both ends of the pipe and use low pressure compressed air via an air regulator to pressurise the pipe. He then heats the dent with the oxy/acetylene torch. ( Did I spell that right?)

EXUP Worldwide