- Wed Aug 17, 2022 11:06 am
#102540
I've been giving serious consideration to an electric vehicle for commuting to and from work. Thing is they seem to be either expensive, slow and rubbish (eg electric bicycle) or very expensive and high performance. No real middle of the road commuters that'll do effectively what a 125 motorbike does.
Looking into the radically modified vehicles regs, it appears if you retain the original, unmodified frame, suspension, wheels and brakes and ONLY change the engine, you don't trigger an SVA test, you can retain the original registration and just register the change of engine.
So, if I did the traditional hub motor, you'd need to do an SVA because you've changed the engine and the wheel and brakes. If I did a stand-alone electric motor with a chain drive to the rear wheel, I wouldn't. Happily, you can buy kits that provide this along with the battery and all the control electronics.
The logical thing would be to find a rolling chassis with a blown engine, ideally a duplex frame which would be simple to bolt a motor to (A Z250/GPz305 springs to mind). However, it occurrs to me that I have a huge stash of enfield bullet parts so if I got a registered frame (our hosts have an Indian 500 frame and V5 on their books right now), I could cobble together enough rolling chassis parts from my shed to make a bike.
Here's the head scratcher though. The bullet frame uses the engine as a stressed member. I'd need to manufacture some stressed members to tie it all together and which will form a base to attach a motor to. I think you could probably just use a couple of bits of box-section between the front and rear engine mounts with a spacer between them and a couple of bracing plates up to the gearbox steady. One of which could even incorporate an outrigger bearing or steady for the motor output shaft.
The electric motor is about the same size as a bullet gearbox so I reckon you'd have loads of room both in front of the motor and where the toolboxes/airbox normally goes for battery storage and I could cut the bottom out of an old tank to house the electronics so you can pop the fuel cap to plug it in.
Given the currently available electric motors, I should be able to fairly easily make something that'll do 60-70mph for 40-50 miles. Increased range is just a case of money and battery storage space but a charge would probably do me a full week of commuting at that. Even an option to use a hybrid voltage so you can run 12v/24v for range vs performance by having batteries switchable between series and parallel.
Cost is a thing. Probably looking at about £1500 for the motor/electronics. Our hosts frame is in at £500 + VAT. There again, you're looking at that much for a half decent electric bicycle which can only do 15mph with a 30 miles range that needs to be pedalled.
Be interested in comments, questions and pitfalls.
Looking into the radically modified vehicles regs, it appears if you retain the original, unmodified frame, suspension, wheels and brakes and ONLY change the engine, you don't trigger an SVA test, you can retain the original registration and just register the change of engine.
So, if I did the traditional hub motor, you'd need to do an SVA because you've changed the engine and the wheel and brakes. If I did a stand-alone electric motor with a chain drive to the rear wheel, I wouldn't. Happily, you can buy kits that provide this along with the battery and all the control electronics.
The logical thing would be to find a rolling chassis with a blown engine, ideally a duplex frame which would be simple to bolt a motor to (A Z250/GPz305 springs to mind). However, it occurrs to me that I have a huge stash of enfield bullet parts so if I got a registered frame (our hosts have an Indian 500 frame and V5 on their books right now), I could cobble together enough rolling chassis parts from my shed to make a bike.
Here's the head scratcher though. The bullet frame uses the engine as a stressed member. I'd need to manufacture some stressed members to tie it all together and which will form a base to attach a motor to. I think you could probably just use a couple of bits of box-section between the front and rear engine mounts with a spacer between them and a couple of bracing plates up to the gearbox steady. One of which could even incorporate an outrigger bearing or steady for the motor output shaft.
The electric motor is about the same size as a bullet gearbox so I reckon you'd have loads of room both in front of the motor and where the toolboxes/airbox normally goes for battery storage and I could cut the bottom out of an old tank to house the electronics so you can pop the fuel cap to plug it in.
Given the currently available electric motors, I should be able to fairly easily make something that'll do 60-70mph for 40-50 miles. Increased range is just a case of money and battery storage space but a charge would probably do me a full week of commuting at that. Even an option to use a hybrid voltage so you can run 12v/24v for range vs performance by having batteries switchable between series and parallel.
Cost is a thing. Probably looking at about £1500 for the motor/electronics. Our hosts frame is in at £500 + VAT. There again, you're looking at that much for a half decent electric bicycle which can only do 15mph with a 30 miles range that needs to be pedalled.
Be interested in comments, questions and pitfalls.
