SWM 280 Mono
My father always wanted to make my SWM 350 Jumbo into a monoshock, but strugled with the centre carb and suspension , plus I rather liked the bike and didnt want it hacking to bits !
I saw this picture some 25 years later and just thought wow it was possible afterall !
I then saw another bike , it looked like an SWM to me but with a Moto Villa engine , what was this SVM ?
SWM to me had to have a Rotax engine and so the next project began ......
SWM 350 Mono
Aprilia TX 311
SVM TRL MJ 329
Aprilia TXR 312M
Armstrong Mono Prototype
Armstrong TA 280 Mono
The above bikes with rotax engines inspired me and I decided to go for a 280 engine and use an Aprilia frame set up, exhaust front pipe and cylinder head. whilst the Armstrong was similar even with its SWM rear silencer, I wasnt sure about the alloy front section of frame. I still had no idea what engine, suspension or brakes to look out for? So the search began ..........
Should I buy a complete bike or parts , well at the time not many bikes about so I ended up with a load of bits above from an Aprilia TX311 rear drum brake version.
Wanted to see what the tank would sit like , so in with the air box and built up the rear subframe, alot of head scratching and looking at this point , biggest area to modify would be the whole of the rear subframe so the seatbase would sit flat on the frame.
Next step was to try an engine and wheels to see how things looked, straight away it was going to need the steering stops on the frame moving if I was to use betor yokes, the Tank is sat on the frame but is not level with the front pipe, then what about the fuel tap!
Look at the rear frame and mudguard mounts all sat far too high!
So out with a tape measure and took some rough measurments from the 350 Jumbo, It confirmed my earlier thoughts the rear frame needed to be altered. Not going to be just as easy as I would have liked........
Front tank mounts made and a coat of paint starting to take shape, came across an Aprilia TXR 312M rear shock, so a quick mod to the front frame and job done.
Basically a complete new top section of the rear subframe including filler panels and seat base mountings.
Okay so starting to feel really good about how things are going but my 320 Jumbo needed its engine back, at least everything now fits and looks right especially the exhaust front pipe, still have a major worry over the fuel tap.......
Look closley at the clutch cover, no water pump just a cover, interesting could I get an Aprilia Climber and turn it into an air cooled?
I was going to buy the Aprilia TXR 312M for the clutch cover and then all the parts, not that many about , one in italy for 1400 Euro that was in very good condition? So what about going totaly the oposite and get a climber for the electronic ignition, hydraulic clutch and so on?
A 1994 Aprilia Climber like the one above came up for sale about an hour away game on lets do it !
A bit damp in the worshop but as you can see air cooled barell and head fitted, hydraulic clutch and rear brake resovoir added to frame
decided to go with a stainless steel sprocket cover rather than the Climber plastic one, used the TX bash plate a bit of rear shaping and fits spot on
The finished product with Aprilia TXR 312 M forks and yokes , Climber wheels , front wheel has different internals and bearings to take the smaller diameter front spindle for the forks. The fuel tap was off the Climber fitted a treat ...... the bike actualy rides really nice just need to ride a trial on it now !
The bike was simply built as a tribute to my father and Pietro Sironi with the intention to ride in modern trials against modern bikes !