Dual Exhaust?

One great thing about a single exhausts is that when the bike naps, there is only a 50% chance you will mess up the pipe.

I dunno......

Not really true Matt, it does depend on the engine. KTM didn't put a dual exhaust system on the $39,000 690 Rally Replica because they cared about looks, and it doesn't make more power or torque than the F800 either. As it should be on a proper racebike, you can not remove a single component (they do supply blinkers and a license plate holder as you will need them in a rally) and keep the bike working well , and many people have tried in order to shave some more weight. Here is what Rob Pollard, an inmate from OZ who raced the Dakar on his 690 in 2010 - and completed it in the 38th position - had to say:

"Yes i did make a single exhaust for it. I could'nt get the performance out of it . Its a shame becuase it was 6kg lighter than the standard system.But there is a good reason they run twin pipes on them and i've gone back to it."

And yeah, they also look and sound sweet.

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I would love to make a dual CF pipe for the 8GS.... If someone with welding skills took it from the cat and back..... It would weigh 6 pounds more than the single......



Erling

So you're saying increasing HP does not constitute an increase in performance :huh

I actually agree that the dual exhaust on THIS motor may not provide much benefit, but if I can add 4 pounds of weight to gain a few extra HP and foot pounds of torque would you not say that I am effectively increasing performance??? Power to weight ratio increase???

And I would still venture a guess that the exhaust pictured is lighter than stock exhaust and provides better flow. The stock can is ridiculous.

Anyway - I've had enough of this nonsense - moving on.

While the pictured exhaust might not be so, its also possible to make two cans smaller than one can, tucking them more out of the way.

We have sort of a long term project for an 800 cf exhaust that employs two cans with angular shapes tucked up under the tank hanging from each rail of the subframe. Something very different than a traditional exhaust--sort of in that RXV sense.

Unfortunately, the cf business is sort of on the back burner right now.

I'm not sure about the regular 650's, but the one on the Dakar is fake (on the right side, IIRC). So you're not wrong!

Bummer.....



Erling

I was afraid my memory was going.

I don't really feel like trying to convince you because it seems you're not understanding a simple concept. I too am tired of discussing it. Not a big deal - I love the look of the dual exhaust, but I won't be modding mine to go that route because it adds nothing but weight over my current arrow headers and leovince pipe.

I *believe* that the right side on the 650 is the CAT. The exhaust goes in and comes back out to the left muffler.

How about that tailpiece?

What tail piece are you talking about?

True, but the fact is, the miniscule differences in weight we're talking about here aren't worth mentioning, let alone worrying about.

The general rule in drag racing is this: All else being equal, 100 lbs. of additional weight = 1/10th of a second added to your ET in the 1/4 mile. A 100 lbs. reduction would equal a corresponding lowering of your elapsed time.

In the case of these bikes, five or even ten pounds will make negligible differences in performance.

In other words, if you like the look and "coolness factor" of a dual exhaust, go for it! Any additional weight involved is not going to affect your performance by any discernible degree.

The license plate holder and the red light attached to it (below the stock brake light).

Performance has multiple levels: next time you drop your F8 offroad and have to pick it up you tell me if you care about an additional 10lbs. Or if you're plowing through deep sand or mud and would prefer a lighter bike.

Seriously, weight matters. I don't see why this is so hard to agree about. We're not talking about 4 wheeled vehicles with big engines, we're talking about two wheels that already weigh more than they should that you ride offroad. If you never ride offroad then sure, 10lbs isn't as much of an issue but if that is the case then why buy an F8. :huh

Because an F8 is good for more then just "off road"

Dyno #'s ?

I will just stick with my tool tube with a bottle of Jameson whiskey in it. A few sips after a ride and you always think you were faster than you really were.

Coming from riding (and occasionally dropping) 800+ lb touring bikes for decades, my opinion is that if 10 lbs is going to make the difference to you or anyone else, on or off-road, on a bike that is still going to tip the scales at under 500 lbs, then it's time to throw in the towel and head for a nursing home.