Exhaust Donuts

[gitrdun]

In all fairness to copper donuts, there are several vendors in the Ads List on this site that have been offering quality copper donuts since 2010. I would guess that there are thousands of users, if not tens of thousands of users and from them we have heard very few complaints. If your flex pipe, your Y pipe, and your clamp are all in good condition, and you install a quality copper donut, and take the time to install it properly, you should be happy with the result. If there is any flaw in any of those components, a graphite or composite donut may be slightly more forgiving, but chances are you are going to be revisiting that repair real soon.

 

[phantomrt]

That is a good point to make, but I don't exactly hear many praises other than the ones about them not disintegrating in relatively short order.

I would upload some pics, but I don't have time to re-size them so the forum server is okay with them.

 

[thor452]

what you hear is from time to time in a unrelated thread I have had copper donuts for XXXXX miles with no problems. not to many have come back to praise them in a specific form but if they were not doing their job there would be a 127 page thread on that for sure. look at the size of the thread on the sidewinder clutch rollers or any other failed part. people are quick to complain when things go bad but not so quick to praise. to the best of my knowledge there is no thread bashing them

 

[twyztid]

There are 3-4 sets of copper donuts installed between my own 06 Apex GT and friend's Apexes. They all have at least 1000 miles on them with mine being the most at about 2800. No leaking issues at all with any of them. I have been very happy with them.

None were bought from eBay. They were all from Sled Toyz or one of the other site venders.

 

[RobX-1]

None were bought from eBay. They were all from Sled Toyz or one of the other site vendors.

 

[phantomrt]

It would be interesting to know what makes them different if at all. They would have to be a softer copper alloy at the very least. Any gasket *has* to crush to conform and make a good seal. That's how all gaskets work. The copper units i have do not crush. I would be willing to send one of the gaskets I have to one of the more reputable vendors so they can explain the difference to their customers. This way, they can say, "hey, this is why you should buy from us!"

But I am really stuck with the mindset that this is a case of where the machines went from having a major leak to having a "good enough" seal, which it was and people left it as that. Will it ever be a problem? Probably not. But that doesn't mean the seal is proper.

Not many others have adapted a Schrader valve to their cooling system pressure tester so they can plug an exhaust tail pipe and use their air compressor to pressurize an exhaust to check for leaks. Most people just see if the engine stalls when plugging the exhaust. It really helps find leaks in plumbing projects before the pipes are filled with water.

Just remember to remove the oil cap, first.... Or risk pushing out the rear main seal.

 

[phantomrt]

https://www.dropbox.com/sh/vchowhf3c6ttjch/AABbu8BYjldRPXMqAhCclejva?dl=0

Pictures of the exhaust stuff...

 

[Carbide]

[QUOTE="phantomrt, post:
On a side note, Dennis Kirk sells the original style units for $9.99 each. And they are about 23 miles from home. Guess what I did after work today?[/QUOTE]
Hey neighbor. It appears I am not far from you.

 

[phantomrt]

I am over near Taylor's Falls... So... Really long distance neighbors I guess. I don't find a whole lot of Yamaha guys around here. They are definitely the minority. Arctic Cat and Polaris stuff is everywhere, however.

 

[Carbide]

I am over near Taylor's Falls... So... Really long distance neighbors I guess. I don't find a whole lot of Yamaha guys around here. They are definitely the minority. Arctic Cat and Polaris stuff is everywhere, however.

That's about 50 minutes. I ski quite a bit at Wild Mountain.
I think all of my 2 stroke buddies will be dis-owning me, so....
Hit me up next season. Looking forward to joining the 4 stroke clan.

 

[apex55]

I have about 1500 on my copper donuts. I also gambled and cut the flanges off my titanium pipes and installed the press fit stainless steel flanges.

 

[RobX-1]

But I am really stuck with the mindset that this is a case of where the machines went from having a major leak to having a "good enough" seal, which it was and people left it as that.

To make that kind of statement knowing the breadth of knowledge of the users on this forum seems a little disingenuous. I know there are quite a few members on here that know a heck of lot more than I do as I've learned from them but I would like to believe I'm capable enough to know when my exhaust is still leaking and when it has a "good enough" seal. For example, I replaced the exhaust donuts on my Nytro last year with copper ones and after a trip noticed a slight exhaust leak. No, it wasn't because I switched to copper donuts and did not have a good enough seal, it was because the clamp on my muffler had come loose and was causing the leak I had heard. Since then, I haven't had one issue with the copper donuts on it or the ones on my Apex. And the success I had with the ones on my Apex is exactly why I never considered going with stock gaskets on my Nytro.

One thing I've learned over the years from this forum is that problems have a tendency to get overblown and over-reported to such a state that it can lead to countless pages of posts where one is led to believe everyone must be having the problem but yet seldom do we see the same behavior when something works. I'm sure the vendors that support this site would like to see those kinds of posts when their products work but just because you don't doesn't necessarily mean their products don't work.

 

[phantomrt]

The thing is, a gasket *still* needs to crush in order to conform and create a seal. That is plain and simple. *All* gaskets must do that. *ALL* O-rings need to as well. If the donut doesn't crush, it is not going to create a seal. If your copper donut is not getting deformed upon installation, it isn't going to create a stellar seal.

I ran this thing for who knows how long with the deteriorated original donuts that leaked. It resulted in zero problems. I couldn't even really tell that there was a "problem" there. I guess if it makes no difference, it isn't a problem. You can run it with only 2% of the exhaust leaking there for thousands of miles and it doesn't make a difference. So, there is effectively no problem and it works well enough.

But I can guarantee that if the muffler was quieter and/or the engine could be under load at 1500 RPMs, people would complain. Nobody wants their snowmobile to sound like an old Ford pickup truck. But with the noise and exhaust leak frequency of 4,000+ RPM before any load gets applied, you can't really tell by sound.

I suppose there is a chance that I messed up somehow in installation. But I would really like to know why the copper donuts I got are inferior.