Whoops, I wrote this last summer and was waiting for some photos so it fell down a crack in the computer. It’s now rather out of date but I’ll follow it up shortly with an explanation of what I’m doing next with the Neuss-B. Basically I’ve decided on a complete rework of transmission and some other things to overcome the problems identified here. I decided that the present arrangement is too complicated and heavy but developments in recumbent bike technology make it worth considering a major upgrade.
So I’ve had my new toy for two months, spent a few days fiddling with the setup and ridden it around town a few times. Today I took a slightly longer ride involving some hills.
First the fiddling. I’ve got the belt drive working reasonably well but the alignment isn’t really right yet and I think the real problem is the Schlumpf Mountain Drive which is still mounted on the old bottom bracket, forcing the belt wheel further outwards and out of line with the front belt wheel and belt tensioner despite a lot of work with longer bolts and spacers.
I can use the MD reasonably well now that I’ve fitted the actuator plates to the two nearly-redundent cranks on the bottom bracket. If I take care to fit the belt so the pedal cranks on the boom are aligned with the dummy cranks below my seat I can use the pedals to position the dummy crank in the upright position, reach down out of sight below me to bash the MD actuator to change ratios and reach back up to flip the gear changers and I’m ready to go again, as long as I have enough momentum to keep rolling while I do all that. Works OK 9 times out of ten but it’s awkward enough to make you stay in high ratio for short hills and that is putting more strain on my knees than is reasonable at my age.
So the next big move is to move the MD to the boom which will require some kind of bracket to support the MD torque arm. Simon Koorn reckons it can work without the torque arm as the bottom bracket on the Neuss boom is chunky enough to take a bevel which will give enough friction to resist the torque (look it up on the Schlumpf website if you don’t know what that’s all about). However I’ve seen the awesome power of the Schlumpf drive in action when I mistakenly fitted the torque arm the wrong way round and it smashed off the little brazed-on cable guide on its self-propelled way round to the right position so I’m happy to do belt and braces.
That will be all good fun as I’ll have to adapt the beltwheel to fit the MD spider and some other adaptations to get it all working happily so I expect it will have to wait a while. Meanwhile I have a reasonably serviceable bike if I can live with the awkward MD change and a nasty squealing noise when wheeling it backwards.
So how about riding? At first it was just very scary and difficult, like learning to ride a bike all over again. Now I’m reasonably confident but I can still get in a tangle when starting off uphill or if I find myself going too slowly. But generally the bike is enjoyable and I can cruise around at quite low speeds. If I am in a low enough gear hill starts are not a problem but I did come to a complete halt on a short, but fairly steep hill today where I could keep going on an upright OK (on the same bike with the same gears in fact) but lost directional control at low speed when pushing quite hard, a lower gear might have taken the drama out of the situation but the bottom gear on that bike is the lowest I’ve ever had. It might be my muscles as well.
Which brings me to how it feels. Obviously it’s great to live without a saddle between your legs but my recumbent muscles are not yet working well so I’m having to build up the mileage. Today I did a short round trip of 10.4 miles including a long uphill and my leg muscles are really complaining so I hope I’ve given them something to think about. My knees are also complaining so I’m a bit more worried about that although my co-pilot on the Pino says that her arthritic knees are very happy with recumbent pedalling compared to walking so I’ll have to hope it’s just a fitness issue.
By the end of the ride I was aware of a little pressure on my buttocks from the very firm foam seat, and my back was soaked in sweat, not surprising as it’s a dense foam on a solid metal seat. I may experiment with some cushioning and in the longer run, if I decide to use the bike seriously I’ll invest in some ventisit seat pads which should do the trick. The other comfort issue I’ve been watching is the harsh ride on poor roads in the city but overall this is not giving many problems, just shaking my teeth loose on occasion when I can’t avoid a pothole.
The ride generally went pretty well. Average speed was well below 10 mph which is not surprising as it was a lot of uphill and I was taking it fairly easy on the climbs, but on the last section which was a steady downhill (Ecclesall Rd South from Dore Moor to Banner Cross if you know Sheffield) the bike really showed its paces. The downhill was not very pronounced but it quickly shot up to 28mph and would have gone faster if the low gears had allowed a bit of input from me. On more level sections where the speed dropped a little and I could pedal I was a bit concerned as the fast cadence seemed to be interacting with the naturally twitchy Brompton to make it feel quite unstable but my feeling was that with the right gears it would be pretty easy to pump it up well above 30mph on any reasonable downhill.
I would say that the weight of the bike is definitely slowing me down on hills but probably not more than our tandem where I’m pulling more than 50% of the combined weight. There is scope to lighten the Neuss-B parts so I’ll work on that in time but meanwhile it’s fun and when I rode it to the Brompton-infused Cyclenation conference last week it attracted a lot of interest as you might imagine. Importantly it folded easily (30 secs or thereabouts) and compactly (think 1.3 Bromptons) so stashing it in the cloakroom with all the other Bs was no problem.
One of the things I am planning is to put a SRAM style adjuster/connector chain on my BWR bike which will allow me to swap the BWR wheel between both bikes. For the same weight that should give me a nice overlap in the mid-range, reducing the number of times I change ratios on the MD, and maybe also giving me a higher top gear.
So all in all, not completely ideal but an interesting bike, fun to cruise round town and real potential for longer rides if I can fix the weight and comfort issues and develop a better recumbent-specific engine.