problem is you have rim brakes. Have to have the correct rim size.
Help - kit recommendations for Raleigh Twenty
- Thread starter Bumtreq
- Start date
A 1000w is going to be illegal also you will have to modify the rear drop outs to do that and lose the 3 speed Sturmey Archer gears. I have seen a few conversions with front wheel drive, plus a significant amount of 20" wheel electric bikes are front hub motors. I used to own a viking 20" front hub electric bike and wish I had kept it to convert my Raleigh.
I have 406 rims. Not sure you can fix the brakes. Relacing the motor may be an option.
What is the width of the dropout?
What is the width of the dropout?
Deffo no problems regarding brakes it is common for these bikes to swap for 406 wheels off bmx and such as the wheels are lighter and give better braking.
If you really want a bike of this type and era the Dawes Kingpin would be better because alloy rimmed wheels are available I think. Doing anything to a Raleigh is difficult because it is either Raleigh specific, imperial measurements, or unobtainable usually.
check the cranks' length.
If it's 175mm then a mid drive is worth considering because the conversion keeps the existing wheels and brakes and has simple wiring.
Mid drive conversion would be very tricky due to the fact the bottom bracket has Raleighs propietary 26 tpi size and the shells are wider than standard at 76mm unlike the Dawes Kingpin which are standard.
I see the problem.
the TPI is not important because most of the bottom bracket motors except the Gospade don't use the BB thread. 76mm may still be possible if you can find a way to lock the M33 nut.
Still, finding another donor bike may turn out to be more economical.
the TPI is not important because most of the bottom bracket motors except the Gospade don't use the BB thread. 76mm may still be possible if you can find a way to lock the M33 nut.
Still, finding another donor bike may turn out to be more economical.
Sheldon Brown's Raleigh Twenty Bicycle Page
This page is about the Raleigh Twenty, a folding bicycle made in the 1970s.
sheldonbrown.com
Like others have said its got proprietary sizes on everything. 80mm-ish wide fork. Need 'Dropbolt' mod to fit decent double pivot calipers, Koolstop Salmon brake blocks and preferably 406 alloy rims for wheels. Bottom bracket is 75mm-ish wide & not BSA std. Rear dropout is 114mm-ish width. Etc. Etc.
Doable, take lot of work, but it'd look cool.
I installed a Bafang BBSHD on R20 recently.....machined 5mm off drive side of BB. Worked out well. I did weld on rear brake bosses for cantilever brake. Safety first , I don't think original brakes are up to the task.Info on standard bike above & other places.Sheldon Brown's Raleigh Twenty Bicycle Page
This page is about the Raleigh Twenty, a folding bicycle made in the 1970s.sheldonbrown.com
Like others have said its got proprietary sizes on everything. 80mm-ish wide fork. Need 'Dropbolt' mod to fit decent double pivot calipers, Koolstop Salmon brake blocks and preferably 406 alloy rims for wheels. Bottom bracket is 75mm-ish wide & not BSA std. Rear dropout is 114mm-ish width. Etc. Etc.
Doable, take lot of work, but it'd look cool.
I've done an electric conversion too, but to a Raleigh sport. If I was to do a Raleigh 20, here is what I'd do...
To keep the 3 speed rear hub I'd go with a 250w front hub, however I'd get a hub thats made for a larger rim, like a 26", and have that laced to your smaller 20" rim.
The size difference between these two wheels is 22%. This will have the effect of giving your more 22% more torque, although it will reduce your top speed by 22%. Top speed is normally 30-35kph on an average 250w hub, so the new top speed will be 23-27kph, perfectly speedy enough for a Raleigh 20!
For the battery id find a 1970s saddle bag, or make a flat cell pack to go in the bottom of your wooden box. A small 10ah battery will EASILY get you to and from work. The longest ride I've done so far is 50km.
To keep the 3 speed rear hub I'd go with a 250w front hub, however I'd get a hub thats made for a larger rim, like a 26", and have that laced to your smaller 20" rim.
The size difference between these two wheels is 22%. This will have the effect of giving your more 22% more torque, although it will reduce your top speed by 22%. Top speed is normally 30-35kph on an average 250w hub, so the new top speed will be 23-27kph, perfectly speedy enough for a Raleigh 20!
For the battery id find a 1970s saddle bag, or make a flat cell pack to go in the bottom of your wooden box. A small 10ah battery will EASILY get you to and from work. The longest ride I've done so far is 50km.
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Agree with a front hub, less hassle- I have just fitted a yose front hub to a trike for under £300, with the following points to note.
Your bottom bracket probably won't take the cassette PAS, and a 2 piece PAS unit will be required.
The threads and nuts on the new front wheel where wider than the original, you should check it can fit the Raleigh before buying. The frame was OK for mine, but I had to 'adjust' the mudguard and front basket fittings.
The biggest issue will be fitting the PAS unit, ensuring there is enough space for the disk on the crank so it spins and getting the spacing for the sensor to read it (there wasn't on the trike and I ended up taking a Dremel to the disk and glueing it to the pedal).
Your bottom bracket probably won't take the cassette PAS, and a 2 piece PAS unit will be required.
The threads and nuts on the new front wheel where wider than the original, you should check it can fit the Raleigh before buying. The frame was OK for mine, but I had to 'adjust' the mudguard and front basket fittings.
The biggest issue will be fitting the PAS unit, ensuring there is enough space for the disk on the crank so it spins and getting the spacing for the sensor to read it (there wasn't on the trike and I ended up taking a Dremel to the disk and glueing it to the pedal).
This is my conversion of a shopper. 1000w Rear hub, 15Ah battery
Its on instructables so you can see how the conversion went
www.instructables.com
Its on instructables so you can see how the conversion went
Electrification & Restoration of a 1970's Raleigh Shopper
Electrification & Restoration of a 1970's Raleigh Shopper: This Instructable is a rags to riches story. I have taken a 1970's Raleigh Shopper/20 bicycle and converted it into an electric bicycle via a 1000W rear hub. I came across this bicycle when I was helping a fellow construction worker...
www.instructables.com
Did the same to a 20 to fit a square taper bottom bracket axle. When I say 'machined' read 'carefully fettled with a flap disk on an angle grinder'. It worked well enough.
Our 20 had the non drive side bearing cup welded in though, which for a mid drive would be further action with the grinder.
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