Copper Exhaust Donuts

[Crewchief47]

About the time the other exhaust donut thread appeared, Sledtoyz was working on getting some samples from a supplier. Those finally arrived today. They are very nice looking, unfortunately they are made out of brass. That was a manufacturer mistake. With the quotes I received at the beginning of the process for Copper parts, these will end up being around $15 CAN each. That is assuming the quote doesn't change with this little snafu of theirs.

My biggest concern is whether or not these will prematurely wear out the exhaust flanges. I'll be testing the Copper versions on the Nytro this season (once they come in) and the first Canadian to get in touch with me may get a sample set to test, assuming they meet the criteria below:

• 
  1. Your sled seems to eat exhaust donuts and you're looking for a solution.
  2. You can accurately measure flange thickness before and after the season and are capable of taking lots of pictures and WRITING the info down.
  3. You are willing to gamble on replacing exhaust parts because Sledtoyz is too small to buy new parts for you and will NOT do that if the donuts wear out the flanges.

Here are the pretty brass door stops anyway.

 

[Zakre]

Well if i didn't already have a set, I would certainly take you up on the offer since I'm Canadian, but I have already installed mine. If i had of known earlier i could have measured the flange thickness for you anyway. I can sure tell you if they wear through cause i am gonna find out! Good luck with them!

 

[Snowmobileaddict]

So those are just paperweights?

Is brass no good because the melting point is a couple hundred degrees cooler than copper?

Is it a hardness issue?

 

[DoktorC]

You've got a PM crew...

 

[Crewchief47]

Snowmobileaddict,

That's why I'm looking for some test sleds. I need to determine if I'm going to be on the hook for worn exhaust components going forward. I have considered selling them with a disclaimer but I don't really want to deal with any poor readers in 2-3 years because they have to buy pipes and manifolds.

You have a reply DoktorC

 

[Snowmobileaddict]

I'm confused.
I was under the impression that you will be testing copper donuts to see if they may harm the OEM Y-pipes or header adapters.


In my earlier post I was inquiring about your note indicating that you have some pretty, brass door stops pictured in your first post. What makes them doorstops? Are the properties of brass not compatible with our exhaust application? Are you going to be testing those brass doorstops and copper donuts in an exhaust application?

 

[2008FxNytro]

They were supposed to be copper, not brass. he is worried the brass ones may be too hard and actually wear into the exhaust pipes.

 

[Crewchief47]

Thank you 2008, that sums it up nicely. I'm also concerned about the copper doing the same but to a lesser degree.

Dok will be getting a set of Brass to test for me, seems he is comfortable with the risk....

To be honest, my gut tells me that they'll be fine in either material but I've seen too many 'weird' things happen to trust my gut at all on this.

 

[hossZ28]

Keep us up to date Chief I am Very Interested ! I work with automotive exhaust systems every day for twenty years and copper has been used for donut gaskets and seals I would reccomend lubricating both sides of the gaskets with a anti sieze paste to prevent any dissimilar metals from galling the only problem I can forsee with the brass Is it may not seal until the pipes warm up

 

[Crewchief47]

Keep us up to date Chief I am Very Interested ! I work with automotive exhaust systems every day for twenty years and copper has been used for donut gaskets and seals I would reccomend lubricating both sides of the gaskets with a anti sieze paste to prevent any dissimilar metals from galling the only problem I can forsee with the brass Is it may not seal until the pipes warm up

That's another of my concerns even with the copper, especially with the clamp system Yamaha uses. An application of ultra copper may help this......

 

[Crewchief47]

I installed a set on my Nytro Yesterday as the exhaust started making noise on our week trip. All I could find of the OEM donuts was a 1" long piece, the rest was GONE!

So I put the Bronze ones in without any sealers at all, put it all back together and started it. Stuffed a rag into the muffler to test for leaks and it sure seemed like it was going to stall if I didn't pull the rag.

I also have a set in Dad's Vector without any sealer. It has around 1600KM on it with those but it doesn't feel like it's going to stall with the rag test, but the RPM does drop some. After this weekend in Muni, we'll pull his down and have a look see.

Dok C has PM'd me with some info that I'm waiting for permission to post or for him to reply here with.

I'm leaning more towards just selling these with a couple disclaimers on wear/minor leakage, especially if i can keep the cost down to the $15-20 each range.

I've spec'd these out a little 'thicker' than the OEM ones mostly to help trap the pipes without bottoming the clamps, which should save everyone from having to grind the clamp to get them to close further.

 

[Crewchief47]

Here's the PM from DokC:

Alright...I've finally got my sled torn down again to check these out.

1200kms (I know...not a lot...but that's where I'm at). They seem to be working great. My clamps aren't turned and there doesn't seem to be any wear on anything.

 

[Crewchief47]

Well, I pulled down the 06 Vector to have a look see. These donuts were installed without any Ultra Copper or other sealer and ran for around 2000 KM or 1200 Miles. When I plug the muffler, the sled idles down some but doesn't stall. I believe its the muffler gasket that is leaking in this case as no matter how tight I got that clamp, the muffler would move around like it was still loose. The other test mule, Nytro, will stall out if I plug its exhaust but it only has 250KM on it's gaskets.

I'm not sure what exactly happened but I could NOT get the donut off the flex pipe....tried channel locks (you can see some witness marks in the pics) and without ruining the gasket I decide to leave well enough alone. Only thing I can figure is that some carbon got under it and filled up any gaps or the donut actually shrunk due to heat cycling. At any rate, I think a cut off wheel and a steady hand would take them off no problem. All three clamps were still tight when I removed them (stock clamps, no grinding off the posts).

 

[steiner]

Put the flex pipes in the freezer for a couple of hours. Might help pop those donuts off

 

[smoothride]

try soaking in transmission fluid and the freezer. transmission fluid is good for penitration oil.