It's summer, and whats better than your girlfriend suggesting a trip to Åre for some downhill bike riding. Now she's a novice without a bike, but, since I've been into biking for quite a few years now, I thought I had enough parts laying around the house that I could just throw a bike together so that she didn't have to rent one. With maybe too much confidence I said: "Great idea, I'll put together a bike for you, no worries!". Two seconds later I realized I had no spare full suspension frame, so whats a man going to do but to build one, in less than two weeks.
So, it's monday morning, coffee break at work, and I need to make a frame, from scratch. Because of the short timeframe I decided to use the geometry from my Specialized Big Hit, but since that has quite a few pivotal points, and those are time consuming to make, I opted for a simple and proven single pivot design. Time to start jiggin', a few bars, some plates and things I found in the scrapheap plus some cones made on the lathe turned out to be a sufficient jig after some (much) alignment, and the rest, as they say, is history.
Compared to my Specialized it's really nimble to flick around the trails. Feels more like a hardcore XC than a pure downhill rig, but then again the Marzocchi Shiver SC fork adds to that. The suspension is very nice despite being single pivot and rocking a low-tier Fox Vanilla R shock. This will definitely be my new XC/light DH bike after some lighter tires have been fitted, but it worked just fine as a novice DH bike.
Here's a bunch of WIP pictures:
Specialized Big Hit FSR mounted in the jig for measurements.
Without any access to CAD environment during the summer, analog was the way to go.
Raw profiles bent to the right shape.
Covering up ends for rigidity and esthetics.
The dropouts used special bolts which was shorter than planned, so inserts had to be made on the lathe that would allow the bolts to be fastened half way through the swing tubes.
Tubes notched and mounted in the jig.
Swingarm pivot layout, SKF bearings, cups made to fit the swingarm tubes etc.
Cups inserted into swingarm tubes, next time I'll leave a bigger collar to weld on. Even with a TIG, these cups were a pain to weld without damaging the tolerances.
Still learning TIG welding.
Waiting for the rear shock, which arrived the day before we set off towards Åre.
