Enduroboxer…
Yes, what about it? The first BMW R80G/S? The airhead that jump-started the career of dualsport motorcycles and dominated the Paris-Dakar Rally?
Yes, that one, on steroids! Or on a diet..? I’m not sure, let’s get into it!
Intro
Inspired by German legends Fritz Witzel, Eddi Hau, and Herbert Schek, Manuel had the idea to enter an 800cc airhead into an enduro rally for twins >500cc. Not the obvious choice, since the airheads are neither particularly lightweight nor particularly powerful. Especially the ones that were originally assigned to the German Police Force. So what did Manuel do to this battleship of a bike to allow him to race in the enduro class and even become German national champion in the Interessengemeinschaft Enduro (IGE) class?
The donor bike
He acquired the former Augsburger bike and reinforced the frame to allow for the abuse he was about to put it through. He designed, cut, and welded reinforcements to the steering head, the top tube, and to the swingarm attachment points. Then, he swapped the original twinshock for a later model paralever. This reduces the reactionary forces of the drive shaft construction and allows for the use of a centrally mounted rear shock. The top of that shock mounts to the main frame, rather than to the rear subframe, which was common standard on the original twinshock airheads. The current subframe Manuel built himself, and hosts the Maico seat and the SR Racing muffler, another weight saver. The elongated design allows for sufficient padding and shifting weight easily in rough terrain. A Preston Petty MX fender prevents the mud from collecting on top of the bike.
The modifications
At the front, all mid-1970’s components have been swapped out for more modern, high-performance parts. A WP AER fork sits in reinforced CNC aluminium triple clamps. These too Manuel designed and produced inhouse. Just behind that sits an aluminium petrol tank, kindly donated by a Husqvarna. The engine sits centrally in the frame and Manuel heavily modified it to suit his needs. Most obvious are the additional oil-cooler, the rerouted exhaust headers, and the hefty bash-plate. Yet something is off when you look at it. If you look closely, you will find that he ground off the top of the engine case, timing cover, and front engine cover to save weight. It currently boosts 880cc and puts out sufficient grunt to get Manuel across the finish line first. It’s not comparable to what a modern 900cc engine would put out in terms of power, but remember that these engines were engineered to be very rideable. They put out an impressive amount of torque across the rev range. And that is saying something! Especially when you consider that Manuel stands over 2 metres tall. Perhaps that’s the secret to his success. He found a niche where he can combine his height, his talent, and his wrenching skills, and compete at the top level. When you see him on his enduroboxer, he whips it around like a dirtbike!
Put to action
What makes the bike so special is that it has been built to ride, and that it is ridden. For many years now it accompanies Manuel at sport events, and they have experienced many highs and lows together (pun intended!). They have ridden the Erzberg Rodeo, Le Tourquet, and the many IGE enduro competitions. And still, it makes him happy to ride! About the bike in his own words [translated from German]: “The motorcycle rides great, it is really fun. One should not forget though, that I built it specifically for myself, and that I massively modified it over the years. A bike so fitting, I would never have been able to buy off the shelf.”
Inspired?
Now if this has tickled your fancy, or if one of our earlier posts about enduro or dualsport boxers did, get in touch with Manuel. During the week when he is not winning on the track, he is giving it his best in the shop. Over 130 frames have been straightened and/or reinforced by their hands. And if you look closely, you will start to see Manuel’s work in many other motorcycles. Frame modifications, custom builds, and parts, SWT-Sports is a one-stop-shop for getting the airhead of your dreams, especially when you’re looking beyond a bobber or cafe racer!
Photos provided by Manuel Schad