Z
zumer
Guest
I'm new to these threads, and I've been reading about the uncertain and inconsistent legislation that you poor buggers have to deal with in the US. When I first got to thinking about a motorised bike, I rang our Roads & Traffic Authority and asked them what the law allowed me. The criteria here is:
200W max.
50cm³ max.
50 km/h max.
Apart from that, no limits, no exception clauses for gearboxes or whatever.
Most gas engines are rated at more than 200W max., but they only produce more at higher revs. In Europe and other parts of the world, the restrictions are similar to ours, except that they generally limit top speed to 20 km/h or 25 km/h.
After considering this, I bought a Sachs motor that's built into the rear (cast, not spoked) wheel, it's been sold for a few years as a "Spartamet", and is pretty well known in Germany and Holland. It's pretty quiet, generates 200W from 15 km/h up (above that speed, a decompressor arrangement between the exhaust and combustion chamber lowers the effective compression ratio, and as a result, the power), and from the factory, has an ignition system that limits the revs to 3750 rpm, 27 km/h. It's good reliable transport, but my daily commute is 40 km each way, uphill and down, and I could only manage to average about 22 km/h. After I'd used it for a while, the ignition system croaked. I went back to pedals only and public trains while I thought about how to handle the repair job. European sites offered derestricted ignition modules that claim to allow the bike to rev out to 35 km/h or so, but there was the cost, the time, having to assemble an electronics kit, and all, so I finally just tossed the ignition system away entirely, discovering that an ignition coil from an old Ryobi string trimmer I had to hand would fit on the laminations of the OEM coil. What a difference! Previously, at 27 km/h, the motor would stutter and fart, as the plug didn't spark on every stroke (which must've been responsible for a few additional unburnt hydrocarbons being dumped to atmosphere), now it doesn't. It'll rev out cleanly. I broke one of the sensor wires on my speedo, so I haven't actually measured it's speed yet, but based on my commute, it's now averaging 28 - 29 km/h, which is only a very little slower than getting through peak hour gridlock in a car. I do wear all the HiVis I can so that I'm safer through visibility, and the local police here wave to me, and wave me through stuff sometimes. Thanks to whoever here in Oz that saw fit to propose sensible legislation, and to the rest of the legislature for seeing the sense.
I'm now working on a bike that's similar to the setup that Daton offers, with a pocket bike engine, except instead of the Daton gearbox, with the CVT belt transmission fitted to some pocket bikes, and a cogged belt drive rather than a chain. I'm thinking I'll probably have to at least partly enclose the belt to prevent pebbles getting wedged between it and the drive cog, and I don't think that standard spokes will cope with the weight and power, because they're breaking with just me providing the motivation. I went to a local sports store where they were offering a yummy Mavic downhill rim and hub with thick, straight spokes, but the wheels are $350 apiece, so I can only admire them from a distance. I may end up getting another cast Sachs wheel and using that, they're about half that price, and trouble-free, except it has an inbuilt drum brake, or I could adapt a disc brake. Rim brakes won't work with them. Maybe I should think about those five-spoke cast rims that're available, except I worry about the rigidity of the rims with that few spokes.
zumer
ps. fergot to mention with all of that is that no registration is needed, 'cos it isn't a motor vehicle!
200W max.
50cm³ max.
50 km/h max.
Apart from that, no limits, no exception clauses for gearboxes or whatever.
Most gas engines are rated at more than 200W max., but they only produce more at higher revs. In Europe and other parts of the world, the restrictions are similar to ours, except that they generally limit top speed to 20 km/h or 25 km/h.
After considering this, I bought a Sachs motor that's built into the rear (cast, not spoked) wheel, it's been sold for a few years as a "Spartamet", and is pretty well known in Germany and Holland. It's pretty quiet, generates 200W from 15 km/h up (above that speed, a decompressor arrangement between the exhaust and combustion chamber lowers the effective compression ratio, and as a result, the power), and from the factory, has an ignition system that limits the revs to 3750 rpm, 27 km/h. It's good reliable transport, but my daily commute is 40 km each way, uphill and down, and I could only manage to average about 22 km/h. After I'd used it for a while, the ignition system croaked. I went back to pedals only and public trains while I thought about how to handle the repair job. European sites offered derestricted ignition modules that claim to allow the bike to rev out to 35 km/h or so, but there was the cost, the time, having to assemble an electronics kit, and all, so I finally just tossed the ignition system away entirely, discovering that an ignition coil from an old Ryobi string trimmer I had to hand would fit on the laminations of the OEM coil. What a difference! Previously, at 27 km/h, the motor would stutter and fart, as the plug didn't spark on every stroke (which must've been responsible for a few additional unburnt hydrocarbons being dumped to atmosphere), now it doesn't. It'll rev out cleanly. I broke one of the sensor wires on my speedo, so I haven't actually measured it's speed yet, but based on my commute, it's now averaging 28 - 29 km/h, which is only a very little slower than getting through peak hour gridlock in a car. I do wear all the HiVis I can so that I'm safer through visibility, and the local police here wave to me, and wave me through stuff sometimes. Thanks to whoever here in Oz that saw fit to propose sensible legislation, and to the rest of the legislature for seeing the sense.
I'm now working on a bike that's similar to the setup that Daton offers, with a pocket bike engine, except instead of the Daton gearbox, with the CVT belt transmission fitted to some pocket bikes, and a cogged belt drive rather than a chain. I'm thinking I'll probably have to at least partly enclose the belt to prevent pebbles getting wedged between it and the drive cog, and I don't think that standard spokes will cope with the weight and power, because they're breaking with just me providing the motivation. I went to a local sports store where they were offering a yummy Mavic downhill rim and hub with thick, straight spokes, but the wheels are $350 apiece, so I can only admire them from a distance. I may end up getting another cast Sachs wheel and using that, they're about half that price, and trouble-free, except it has an inbuilt drum brake, or I could adapt a disc brake. Rim brakes won't work with them. Maybe I should think about those five-spoke cast rims that're available, except I worry about the rigidity of the rims with that few spokes.
zumer
ps. fergot to mention with all of that is that no registration is needed, 'cos it isn't a motor vehicle!
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