KTM LC8 Exhaust and Auxillary Tank

[neduro]

This isn't technically a business yet, but since I'm considering it, I thought I'd start a Vendor thread about it.

I want more fuel capacity for both my 950 SE and Adventure, and after lots of poking around, the preferred alternative I can see is making a 2 into 1 exhaust, and replacing the other exhaust with a fuel tank. Both the Adventure and SE are already a bit front heavy (the Adventure much more so than SE) which rules out a bigger front tank.

The design parameters for the rear tank would be that it had to work with all common luggage racks and passenger pegs, it has to provide at least 2 additional gallons, it has to weigh less than stock when empty (including the exhaust on the other side) and it can't sacrifice power.

I believe that one tank shape can be made to work on both SE and Adventure (and presumably SM, although that's pure speculation for the moment on my part), with different 2->1's required for each application.

Here's a post about the project from Orange Crush:

Originally Posted by neduro

I'm embarking on the project many of us have thought about: building a 2 -> 1 exhaust, for the specific purpose of creating an empty space for more fuel capacity.

Ultimately, this post may turn into because making one may not be much less expensive than making a bunch, in which case I'd start a business to sell them... but since I haven't made any sort of decision yet, it's not spam yet.

In anticipation of questions about that, I started a vendor thread here so that we don't junk this thread up.

I'm lucky to have both an Adventure and Superenduro right now. I'm starting my work on the SE because it was already in pieces, but these same concepts will work on either variety.

Anyway:

First step was chopping up a stock "H" pipe to turn it into a 2 into 1.



Here's the finished product:





I believe that it will be necessary to make a larger diameter pipe past the junction, but I have dyno time reserved this week to find out for sure. I'll be testing the bike full stock, with 2 neptunes (baffles in and out), and with 1 neptune. I won't have time to change jetting between pulls, but I suspect we'll learn something anyway...

Mounted:


Then, I took some styrofoam and mocked up a tank shape.



Used packing tape to attach mounting points:



Glassed the top in to make it a bit more durable:



And presto-wallah, a reartank prototype for the SE:





Ultimately, the shape needs a little tuning, but it is ergonomically excellent (no edges to catch, impossible to feel when on the bike), is out of the way as the swingarm travels, improves the balance of the bike front to back, and will give over 2 additional gallons. Because of the length, I believe that the finished product should be filled with baffling foam to avoid a back to front slosh (or vice versa) under braking.

I've been kicking around constructions for the tank with a bunch of folks over the last few weeks, and it's been an interesting learning experience. The two methods that seem most practical are forming aluminum, and rotomolding.

The advantage of the aluminum option is that the cost for the first might be lower, but I anticipate that it would be easy to dent in a fall, and I worry about the effects of vibration on aluminum over the long haul.

Rotomolding costs a lot to make the first one... but I'm meeting with a vendor this week to find out just how bad the damages would be.

Anyway, I'll report the facts here. I think this will be an interesting one to play out!

If you're interested in this project, please let me know. If the response is strong, I'd be more willing to invest in a way to produce these for a reasonable cost (ie, take the risk on buying a mold).