Sunday, July 1, 2012


Welcome to Pt II of my Mobec Duo-Drive Sidecar Conversion on my 2004 BMW 1150 GS Adventure.
If you would like to find out more of the backstory on how I arrived at this point, you can read it in Pt 1 here.

The base motorcycle that I'm using for this 2WD Sidecar Conversion is my 2004 BMW 1150 GS Adventure that I've been riding on the road on my trip full-time for the last 2 1/2 years, and its all stock internally. 
Some of the external modifications I have made to it include a Touratech 41 liter Nylon tank, it's one that I came across used that came with the fuel pump, fuel plate and it was already painted silver. I drilled out the filler neck to make it a 44 liter capacity tank, and at the end of the day it was less than half the price of buying the tank new. 
I prefer the look of this larger tank much better, I think it fills out a lot of space between the tank and the top of the cylinder heads, but it is a huge tank. When you put one of these big tanks on, you have pretty much removed the 'Dual' in this "Dual Sport" motorcycle, as it becomes just too top heavy to really take it up the side of a mountain and try to keep it upright. To be honest, the 1150 or the 1200cc motorcycles I don't really consider 'Dual Sport' anyway, even though they call them that. In reality they're an enduro styled road bike with some off road capabilities. Many will disagree, but I rode it in the 2011 NORRA Mexican 1000 and even removed the panniers and rode the 400 miles on one of the stages, 175 miles of brutal washboards, the rest pavement, so I can tell you from first hand experience that it's NOT a dual sport bike, even with a stock tank. An ideal 'Dual Sport' bike should be around 600cc, no more. Even an 800cc is really too big.

Another modifaction I made was to build a set of extension drawers underneath my Touratech Zega panniers (which I also bought used too). 
I got tired of having to remove everything in the pannier to get to the tools in the bottom, and my clothes inevitably ended up smelling of fuel or oil, so the drawers keep tools and other items away from food and clothes, and make the tools so much easier to access. There is room for tools in one side drawer and parts or camping items in the other. I estimate they're approximately 14 liter drawers, which is a 33% increase in space over the 44 liter panniers.
The pannier build can be seen on my blog here if you feel like having a go at it yourself. Email me with any questions you may have, I'll be glad to help.

I also replaced the OEM shocks after I blew the rear out at 45,000 miles with a set of Wilbers, and then the Wilbers blew the rear seal at 7,000 miles, so I sent them back and got the seal replaced under warranty. After 5,000 miles the newly replaced rear seal blew again, so thats where they are right now, blown and off the bike. I've heard other stories on the forums like this about the Wilbers shocks, so I may just go to another shock all together for the sidecar.

Ok, back to the sidecar build.

This is how you get a Stern Rox from the factory, minus the tire.

The sidecar I've chosen to use for my 2WD Sidecar Conversion is a Stern Roxster or Rox, a 1 1/2 person chair, more of a road going performance sidecar than an Overland chair, but in talking with Ad Donkers of LBS Sidecars  where I'm building the outfit, we both decided from the outset to do something different rather than follow in others footsteps. 
Again, you can refer to the backstory for the selection criterion I used in choosing this particular sidecar.

From the start I had a pretty clear picture in my mind how I wanted the outfit to look when it was completed, but since I got here to Holland and we started to dismantle the bike and fabricate the framework, the original design I had in my mind has now changed, but changed for the better. 
Some of the features we decided to incorporate into this 2WD outfit will be very unique aside from the Mobec Duo-Drive, one of them being a locking hub on the sidecar wheel scavenged from the front end of a Suzuki Vitara 4X4
I wanted to put in a locking hub on the sidecar wheel for a couple of reasons, first because it would be a neat piece of engineering to fabricate, and second because it will allow me to turn on and off full-time 2WD which will cut down on tire wear and also gas consumption, and for on-highway use, 1WD will be better for handling than 2WD. 

 So after a trip to a salvage yard we started out with this....

....and with steady hands of a surgeon "carefully and delicately" removed some of the excess metal with an angle grinder..... 

....trimmed it up a bit....

...put in the milling machine, and after a couple of hours this is how it looks finished and painted.

A Suzuki Vitara 4X4 right side front hub with the half shaft......
........and the locking hub.....

...which will be attached to one end of the Mobec Duo-Drive unit on the right.

Here I'm removing the ABS unit. I always turn off the ABS when I ride anyway, I just don't like ABS, I prefer riding by feel and experience, and it will free up enough space under the tank to use either 2 Oddessy Motorcycle Batteries or 1 full size car battery, we haven't decided yet. It also shaves about 12lbs of weight off too, which by the time we're finished will be added back tenfold I'm sure.

A symbolic moment for me in this transformation or conversion from motorcycle to sidecar.
I had already removed the centre stand back in the US before I shipped the bike over to Rotterdam, so removing the side stand was the final part that when removed, you know you no longer have a 2 wheel motorcycle anymore, now it's official that something is changing.

Stuff I won't need from my former 'Motorcycle', soon to be sidecar. ABS unit, a Touratech Rear Rack extension, side stand, assorted lines and the crash bars from the engine.

We are currently finishing up the sub-frame for the motorcycle and the front end leading link. The wheels I have already chosen and all 4 just arrived this week here in the shop, 3 for the outfit and 1 spare wheel and tire.
By next week we should be working on the sidecar frame and fitting the Duo-Drive underneath the sidecar.

The build or finish time has not yet been determined, the only time constraint that we have put on it is that it should be ready ready for this years EGT, 
European  Gespann (sidecar)  Treffen(rally).
Then as soon as the EGT is over, I pack up, leave Holland and I head up to Nordkapp in Norway to test out the 2WD system and also to officially start my expedition.

 I hope you all enjoyed this installment of my Mobec 2WD Sidecar build.

Comments and questions are welcome.

Have the day of your choice.......


Post a Comment