Husqvarna 701 Enduro Extra Fuel

I have a 2023 Husqvarna 701 Enduro motorcycle. I love this bike. One of the challenges with this design is there are not many options for carrying additional fuel for longer rides. The stock rear-mounted fuel tank carries 3.4 gallons, which gives a range around 160 miles (I average about 50mpg). The low fuel light generally illuminates at around 135 miles. This is adequate range for the vast majority of my rides. Occasionally we want to ride a longer loop that has not fuel stations and I need to carry extra fuel.

I started with a cheap Amazon 1.3 gallon Rotopax copy fuel can. It was under $40, and very poor quality.

The plastic mount broke on the first ride so I reinforced it with through bolts.

There were still several issues. The aluminum plate was cantilevered off the side of the rear luggage rack. When riding in rough terrain the luggage rack would flex. I was concerned with fatigue failure longer term. I attempted to find another anchor point but there is not any point available on is bike. I even considered pannier racks to mount the can but I preferred to not add all that bulk and weight. I also wanted to carry the fuel as low as possible in the bike.

Over the years Husqvarna had offered a long range version of this bike which added front tanks. There was a long range kit available from Husqvarna to add this too. It costs $1,800 and added complexity. I also did not care for the look of the bike with this option. I have occasionally seen some aftermarket variants of that design.

There is an aftermarket kit from Rade Garage that replaces the air box with a  1.5 gallon fuel tank and a small air filter. It seems to be the most popular option and it is much less expensive than most other options. However, I prefer to retail the factory large air box since this is a single cylinder engine and that large airbox volume serves a purpose for better airflow to the engine. There is a good reason Husqvarna (KTM) designed such a large volume between the air filter and the engine intake. I do not want to sacrifice that.

I finally broke the mount on my cheap gas can again. The spout assembly always leaked and was hard to use as well. It was time for a better solution. All solutions come with trade-offs. I wanted to move to a better quality fuel contained and Rotopax appears to be the best. Most of their cans are more focused on 4x4 and not motorcycles. I did not want to use my rear rack to carry gas as I already use that for my tail bag. I wanted it to mount low, and I wanted minimal mounting hardware. I also wanted to be able to remove it quickly since I rarely need to carry extra fuel. I decided to get the 1.5 gallon Rotopax Rollpax. I made my own mount that slides over the passenger footpeg.

I made it from steel I welded up. Ideally a robust plastic mount would work better here and be lighter. I wanted to build and test this location so steel was quick, easy, and strong. I used 2 4" exhaust clamps to attach the Rollpax to the mounts. I added a Velcro strap to the foot peg mount to retain it. On the top I reused the aluminum plate I had made for the old can. I added a threaded knob to the top mount to attach it to the aluminum plate. I added a rope holder to ensure the knob could not loosen while riding.

I used Loctite on the clamp nuts to prevent loosening (except for the knob). I added a strap attaching the Rollpax handle to the rear rack as an extra safety measure (likely unnecessary). 

I can fill this can without removing it and it does not get in the way of anything else either. When I need to put this fuel in the tank, I remove the straps, the knob retaining rope, and the knob. The whole assembly comes off in one piece. 

Since I rarely need to use this extra fuel, everything removes with the tank except the aluminum plate which is not in a way of anything and it is very light. 

The downsides:

1. This uses the passengers foot peg. I cannot ride a passenger with this tank in this position.
2. While the weight is down low on the bike, it is also on one side of the bike.
3. There is real risk of breaking the passengers foot peg if I dump the bike on this tank. I am not the most skilled rider so this is a real risk.

The upsides:

1. I can remove everything except the aluminum plate with no tools, and quickly. Since I don't need extra fuel the vast majority of the time I am not carrying this extra bulk and weight when I don't need it.
2. Most of the weight is supported by the passengers foot peg, down low on the bike. This reduces the weight on the rear subframe compared to carrying a tank on the rear rack or panniers. 
3. I did not alter the air intake or the fuel system on the bike.
4. I can use this to fill other bikes if needed.
5. It cost less than other options. The Rollpax was about $220 (not cheap) but the rest was basic hardware and labor.
6. This extends my estimated range to around 240 miles.

In a pinch I can also strap it to my rear handles like this.

Next steps are to fill it up and ride some rough trails to validate the design. Once validated, maybe consider a production optimized design, likely using more plastic and not steel. Likely make a simpler and more robust attachment mechanism for both the top and bottom.