Week 12

Following a week off it was back to work on the sidecar conversion project. New massive rail loops were added, together with rear tubulars to allow mounting of the larger seat base, back rest, and rear cargo box. New reaction post and new links were made to accommodate the additional weight, and the fender mounting was redesigned to accommodate the bicycle rack that will sit above the sidecar wheel. This week its onto the aluminum panels, then blasting and painting.

Week 10

We collected our first clients outfit from Buena Vista this week. This was previously my own personal outfit that was sold privately through FB a few weeks earlier. The new owner contacted us to make some changes to the outfit, primarily to accommodate his dog, but with a few additional requirements mixed in. 1) Keep dog contained / secure when owner pops into a shop, etc, and provide shade. 2) Relocate compressor etc and structure to give full floor space. 3) Extend floor at the front and side. 4) Replace seat with a removable base. 5) Add bike rack and ability to carry a surf board or snow board. 6) Include removable access door to the side. The original request was also to include a cantilever roof, though following discussion it was agreed as impractical. Original upper frame was removed with a lot of grinding and new material is awaited from the steel suppliers.

While waiting on material for the sidecar conversion, I finally received the long overdue Hagon shocks for the leading links, so got to work on the mounts, which also involved repositioning the caliper mounts to ensure adequate clearance. Before breaking it all down for shot blasting, I used the my laser tool to check the final trail, which came out at 2-1/2" nuts on, giving me a 2-1/4" if reversing the heim brackets.

Week 9

For the caliper mounting I wanted a design that would be truly universal. Typically, the mounting would swivel about the axle, whilst this would be easy enough on my R1200 axle (lots of space on either side of the wheel hub), it would be impossible on models that have a mechanical speedo mechanism on the axle (R1150, R1100, R100, etc), unless of course both calipers where mounted on one side, which is a compromise I can’t live with. Regardless, in addition each swivel / bearing would need to be be-spoke to that particular model $$$.

My initial compromise was to use a Heims just above the axle mounted to the swingarm. This arrangement, whilst universal, does mean the calipers will raise and lower on the rotor as the suspension strokes, though only by approx. 1/8” and the positioning has to accommodate that. I have used male Heims either end of a tie rod to accommodate the braking load. I will change this going forward to females and use threaded rod to allow more clearance for the shocks.

After tweaking the geometry some, I managed to get a full 6” of travel without binding or loss of pad contact. However, I was not overly happy with the arrangement, so have decided to instead pivot out-board of the axle with small bearings. Bonus benefit of this is that I can get the tie-rods further in-board allowing the shock mountings to be a little narrower. Just waiting on the parts to arrive so I can finish up the brakes.

Whilst waiting on parts for the leading links, I got to work on the modular platform sidecar. The extra wheel base from the links has made subtle changes to the sidecar lead and track width, but I think I've got a nice combination of 47-1/2" and 10-1/2". Hoping this will result in nimbleness with good stability. Below are some rather nice coped welds by Finley.

Got the new out-board caliper mounts made and mounted up. Takes a little more work than the above axle pivot, but its a far better and neater solution. You can see how tucked in the tie-rods are, leaving plenty of space for the shocks. Just waiting on the shocks to get the build finished.

Week 8

Seem to have forgot to take pics along the way this week. Anyway first off was to install the new self aligning upper tree bearing, went in a darn site easier than getting the other one out. However, I need to get the ignition switch off so the upper tree could be repainted, and that was a PITA. BMW had used anti tamper screws, and torqued them in so they could never been removed, as such I had to drill them out and replaced them with studs so it could be removed again if necessary.

Next I made the lower weld-on brackets for the lower tree using 3/8" plate. Heim joints arrived for the leg pivots, and next I got cracking on the upper attachment for the legs. Here's where I had a Aha moment. Rigidly mounting the upper leg to the upper tree (having already removed the redundant ball joints) would mean load (a lot of load) would go through the upper tree rather than through the lower tree, tele-lever / swingarm, and strut into the frame. The result likely to be a fracture of the upper tree (considering it was never designed to take vertical load). Best solution I can think of is to eliminate the rubber bushing from the strut (replaces the front shock), and use stiff bellville washers between legs and upper tree, this will allow the load to be taken by the lower rather than upper tree.

Last bit for today was to knock out the strut, made from 1" aluminum bar with a solid 3/8" x 1/2" rod end to mount to the tele-lever, simple enough, but yet another machined sleeve needed to keep the narrow rod end in the center (lower shock mount was a lot wider).

Fork legs bent to ensure symmetry, and tube inserts machined and welded in-place.

To the right, one of several bizzar tools made-up to ensure alignment is assured.

Next I got to work on the bender and I seem to have got bend measuring nail, as the two legs came out identical without any adjustment. Getting the leg mounts perfectly aligned was pains-taking, but the upper and lower tube inserts was a breeze. Once all tacked I had the prodical son finish up the welds. The next step of getting the pivot points aligned was a complete nightmare and took hours before it was ready to tack in place. Lesson learnt here to not use a bolted lower tree (used on the R1200R), but instead to use the GS lower tree which clamps around the fork tubes.

Swing arm set-up ready for tack weld. Getting each leg identical took a lot of (measure, check, measure again), I did a trial run first to get the process down, and this ended up to be within 1/16", so plenty good enough. One axle sleeve is threaded, and the other will be cut to add pinch bolts, allows use of the stock axle.

Had Fin do some test runs before welding the sleeve and making the splice. I used a bung to make the splice easier and to guarantee stength in the joining weld. Result turned out just dandy.

Set the swing are to accept a 19" wheel if I later decide to switch out the R1200R wheel. The symmetry end-up nuts on, so should be good to get started on the legs next.

Finished the pivot rough out, this will accept 3/4" heims. Tied a a few other option, bronze insert solid hiems and even a set of custom machined bushings, but the alloy steel heim seemed the best solution for affordability. The pivot brackets are asymmetric to give two trail option (or multiple with custom side plates.

Wow the upper tree did not want to budge, had to make some special tools to pull the pin out, and another special tool to remove the ball joints. Life is a breeze when you have the right tools. The upper tree bearing will be replaced with a self aligning one to allow the tree to follow the solid legs between upper and lower, but also the ball joinst become redundant to I will replace them with sleeves and M12 fasteners to ensure strength.

Week 7