Wow. Capac is a beast. On the surface there was little technically 'wrong' with Capac, however I wanted to pull out all the stops to make it the ultimate unitrike. So here's the lowdown:
The turning was a bit stiff as the truck tensioners were the plastic skateboard style so I replaced them with two rubber table feet and an extra rubber washer for the appropriate padding. Hey, it may not be high-tech but you can't argue with the results :)
As the pedals are mounted much higher on Capac than on the other unitrikes, I needed the seat to be correspondingly higher up. The trouble was that the only way to do this was to replace the seat post and finding a 25mm seat post is not an easy job these day. After a lot of searching Wiggle.co.uk sorted me out :)
The previous owner had replaced the original truck and wheels with extra extra large kit (which rule - a 100mm wheel handles the bumps so much better and the wider truck adds a good bit of stability) however the solid plastic wheels make for a lot of vibration in the ride. I inserted a 1/2 inch rubber shock riser against the truck (which also necessitated longer truck fixing bolts) to add a little suspension and push the centre of gravity a little further back, allowing for better stunts!
At this point I should mention that in addition to the new truck and the wheels the previous owner had added two inches of metalwork betwixt truck and frame to move the centre of gravity back which allows for better bump handling and stunts.
Now to the brake isssue. Capac came fitted with a cable brake - lever mounted under the seat connected to a caliper brake above the back wheel. I quickly replaced the brake pads and cable but still had issues with the mounting of the lever. Where it was mounted makes it difficult to operate, compromises balance and makes it look like your scratching yourself when you use it. Not good. So my idea was to make another brake to work in parallel with this one that I could hold in my hand as I ride. For this I would need a new brake lever and a bar end (aka bull bar) to form the two sides of the handle. An additional extra long brake cable would give enough slack to allow a good range of arm movement while holding the handle and could be attached at the brake caliper to work alongside the original brake. I should point out that the original brake is staying where it is untouched, as if I were to drop the 'hand brake' I would need a backup to avoid plowing face-first into the number 47 bus.
This was where the only bit of metalwork I had to do was involved. I had to get two brake cables to connect in parallel to the brake. There was already the hole from the original cable sleeve clamp in the brake caliper and I could easily get hold of a pair of matching cable sleeve clamps. The trouble was connecting the clamps to the caliper. What I used was a 1 inch washer and put three holes in it in a triangular formation allowing it to be fixed to the caliper at the top with the sleeve clamps side by side below. The beauty of the sleeve clamps being close together and below the caliper bolt is that when the brakes are applied only a very small turning force is produced. If the sleeve clamps were further apart or on the same level as the caliper bolt then much of the movement of the brake cable would be transferred into simply rotating the clamps relative to the caliper. Of course this would be reduced with extra tightening of the caliper bolt but the problem still be there. Works like a charm.
I also glued the other ends of the brake cables into the levers as, when one lever is operated, slack is produced in the cable of the other lever and this can allow the end of the brake cable to pop out of the lever.
Since bar ends come in packs of two I was in the delightful position of having a spare which I mounted at the top of the seat post just below the original brake lever to use as a stunt handle.
Due to the longer wheel base, I realised that I would be able to attach stunt pegs without them getting in the way of my feet as I pedalled. They will make for some interesting riding. The only problem being that once your feet are off the pedals your centre of gravity is brought well back - there is a much bigger danger of the seat falling backwards and the unitrike flying out in front of you.
Finally, the tyre was pretty perished, the tube valve seemed to have a slow leak and the seat post clamp had a big loose bar through it that was scratching the paintwork so I replaced all three. Final blinging touches then included a retro aluminium mudguard, a pump and water bottle clamp and a mini saddle bag. Dude.
After riding well for a while, one issue that reared its ugly head was the brake cable getting caught between the rear wheel and the mudguard. This completely trashed the sheath of the original cable brake so I put a new lever/cable assembly together and used a 2 inch length of plastic pipe to guide it along the frame and away from the wheel. Works like a charm!
When Lazarus first arrived I seriously doubted that anything could be done for him. Where there wasn’t rust or 10 years of grime there was bright pink paint. The chain was completely seized up, the back wheel was out of alignment and the seat bolt was useless. However after a lot of cleaning, sanding and oiling, a new quick release seat bolt and a new paint job, things were looking up.
The first job was to realign the back wheel as this was causing a whole host of problems - slight right hand turn and slipping chain being the most important. This was quite easily done however it requires an extra person to keep the wheel correctly aligned and the chain tight whilst tightening up the wheel nuts.
Next we had to tighten and balance the truck suspension. The suspension is by means of the rubber plate between the truck and frame and is tuned via the bolts at each corner. Too loose and your truck will slip and spin relative to the frame, too tight and the suspension will do nothing, imbalance the bolts and the unitrike will lean.
Finally the truck bolt needed tightening. The truck bolt attaches the axle to the truck base and controls how easy it is to turn by tightening the rubber washers that are on either side of the axle. Too tight and you will have trouble turning at all and find yourself going up on one wheel. Too loose and you will lose stability. This is a very personal alignment - being a tall person I have greater leverage on the truck and so prefer a tighter bolt, my housemate however is shorter and prefers it looser.
So all was well with Lazarus until disaster struck! The plastic truck wasn’t strong enough for the action it was getting and snapped along one side. This meant that turning let felt normal enough but there was no resistance whatsoever in a right turn and you could easily find yourself with your shoulder planted in the ground.
So a new truck was needed. I bought a skateboard truck and then drilled additional screw holes in it to align with the plate on the frame. The wheels were permanently attached to the old truck so needed some gentle persuasion with a hacksaw to be extracted. However, without being braced at either side by the truck they would not stay attached to their bearings and had to be jettisoned.
Then we met the major difficulty - the new truck with normal skateboard wheels causes the front to sit too low producing instability, lost rear traction and seriously compromised handling of bumps. Bigger wheels would fix it however too big and they could get in the way of the pedals, particularly on turns as the unitrike leans.
The ultimate answer, beyond managing to source a new unitrike truck, would have been a balance between extra large skateboard wheels and adding spacers between the truck and the frame. However I looked into skateboard wheels and couldn't find any under £30 and since £30 is about the average price of my unitrikes I was reluctant to fork out that kinda dough. So what I did was go to Homebase and for £1.49 each I got hold of two 100mm by 15mm trolley wheels and bored out the holes to make them fit the new truck. The wheels are big enough to give a very nice front/back balance and also thin enough so that although they overlap the pedals, they come up the inside and out of the way. They have no bearings and will probably last 6 months tops but hey, then I can just get some more!
Also I should note that the smaller width of these wheels makes the left/right balance a little more twitchy and the new truck does not turn as well as a unitrike truck. However since fitting an entirely new set of truck tensioners it is the bomb for reasonably straight journeys and learning.
Finally I had to face the facts that Lazarus was never going to be a viable unitrike, since the new truck and wheels lacked sufficient stability and turning control and a worrying grinding sound had begun to emanate from the bearings within the pedal mounting. This time Lazarus shall not rise again, he has been stripped for parts and sent to the great skate park in the sky.