Donor Bike for a new e-bike Conversion

Looking for a sensibly priced strong and light mountain bike style frame for a new e-bike project (front hub motor 36V).

 

What make should I be looking at that are relatively cheap, strong and relatively light that could be converted into an e-bike ? It will only ever be used on road so not really interested in front shocks etc.

Would you not be better with a hybrid ?

 

I have recently been considering a town bike and as I we live in Cambridge, looking at 3 speed internal hub equipped bikes.

 

So far I am interested in these

 

1. Raleigh Pioneer 3. I like it comes fully fitted with guards and rear rack.

 

 

 

http://images.rutlandcycling.com/images/pn318mbl.jpg?width=644&height=644

 

2. A Creme Cafe Racer Solo which is a little retro

 

http://media.chainreactioncycles.com//is/image/ChainReactionCycles/prod86187_IMGSET?wid=500&hei=500

Then again I might look at an old frame to build up.

 

Jerry

Any bike will do, but avoid ones with twist-grip gears. Also, look for a gap of at least 8mm between the pedal crank or chain-wheel and the bottom bracket so that you can fit a pedal sensor.

 

Suspension makes a bike much more comfortable on the road, and many non-suspension forks don't have much meat on them to be strong enough for a motor.

 

Disc brakes are better than rim brakes.

 

Something like a Carrera Vengeance is good, or the Kraken if you want a bit more.

 

The very cheap ones are also OK, but the suspension is not so good; however, they often have steel forks for strong motor installation.

Disc brake wise, I am not sure you gain a lot over rim brakes unless they are hydraulically operated. Many of the cheaper disc brake bikes are cable operated.

 

Jerry

Disc brake wise, I am not sure you gain a lot over rim brakes unless they are hydraulically operated. Many of the cheaper disc brake bikes are cable operated.

 

Jerry

 

I agree. I have had several mech disk, and rim brakes. Good rim brakes (linear aka V brakes) are just as good as mech disks for road use. In fact, I would say that my rim brakes require a lot less fiddling than my disks.

 

Hydraulics are a different story from what I hear....

I like this Globe Works 3, but the cost is creeping up. Of course probably because it has a 7 speed hub on it.

 

Jerry

Jerry, do you know any good motor that would fit the front fork of this this Globe Works 3?

Well if I get one I would be thinking about either a Tongxin or Keyde motor but then as everyone knows I am biaise about these motors and my commute/rides are in and around flat Cambridge.

 

I guess any 100mm spaced motor would fit those front forks, though depending on if they are steel I would probably limit it to 250W.

 

Problem is all my motors are 260RPM which will be way too fast lol

 

I am pretty sure there is one in a shop near me so I may go take a look. Twist grip shifter would be problematic to fit a throttle on the right side.

 

Ps Full details of the bike here.

 

Jerry

Edited March 2, 201412 yr by jerrysimon

 

Hydraulics are a different story from what I hear....

 

Good hydraulics require no adjustment or maintenance, which is about as good as a bicycle brake can get.

 

The other thing that occurs to me about rim brakes and a hub motor is changing the wheel is more complex when the rim wears out.

Concerning hybrid bikes, when I was testing a few a couple of years ago I particularly liked Marin bikes (Larkspur was my favourite) and of course they do loads of mountain bikes too. Globe (Specialised) bikes are generally a bit cheaper (which is why I bought one but I was always a bit disappointed in it in comparison to the feel of the Marin). When it comes to brakes, I have to say the best I have experienced are Magura HS11 Pure hydraulic rim brakes. Long lasting, self-adjusting, zero maintenance and stop great even in the wet. Much better than the Shimano hydraulic disk brakes on my Scott SUB.

....The other thing that occurs to me about rim brakes and a hub motor is changing the wheel is more complex when the rim wears out.

 

 

Don't know how far a rim is expected to last with rim brakes, but mine has lasted more than 1500 miles so far. Even if it needs changing, a new high quality rim is £20-30, and it took me a couple of hours to change and true after I destroyed a rim a few weeks back (pothole). I guess a good bike mech could do it in an hour or less.

Not sure about larger rims, but I have 5000 miles on one of my Brompton rims and its still going. I am told that smaller rims wear faster.

 

I keep meaning to check out some Marin bikes.

 

Jerry

When it comes to brakes, I have to say the best I have experienced are Magura HS11 Pure hydraulic rim brakes. Long lasting, self-adjusting, zero maintenance and stop great even in the wet.

 

I can't agree with that, sure for rim brakes they are good, but they're not self adjusting and they're not very good in wet weather, and not that long lasting either.

If you are only going to use the bike on tarmac I would suggest you get as good a spec hybrid as you can afford. My Specialized Globe Pro ( well looked after but 7 years old before conversion ) with an Ezee kit is amazing. The 700c wheels with road tyres roll along easily and the 27 gears combined with the grunt of the Ezee motor make steep hills a doddle. If I was doing your project I would spend time hunting for a really good value well specced previously owned donor bike, leaving yourself a bit more cash to spare for a top end kit. More than happy with my V brakes.

I can't agree with that, sure for rim brakes they are good, but they're not self adjusting and they're not very good in wet weather, and not that long lasting either.

Well I can only go on my experience. Used pretty much daily for over a year, come rain or shine - over 2500 miles - up and down many 20% gradient hills and they still work great without any adjustment.

Well if I get one I would be thinking about either a Tongxin or Keyde motor but then as everyone knows I am biaise about these motors and my commute/rides are in and around flat Cambridge.

 

I guess any 100mm spaced motor would fit those front forks, though depending on if they are steel I would probably limit it to 250W.

 

Problem is all my motors are 260RPM which will be way too fast lol

 

I am pretty sure there is one in a shop near me so I may go take a look. Twist grip shifter would be problematic to fit a throttle on the right side.

 

Ps Full details of the bike here.

 

Jerry

Hi Jerry

 

I'm considering buying a Keyde 36v 250w rear hub motor to fit in a 700c wheel.

Could you advise me as to the best RPM to go for ?

 

Thanks

Bill

Well anything lower than 260RPM given that is what I use in my 16/20" rims.

 

I think a lot of people use 160-220RPM but as I have yet to dabble in those sized rims probably other's here can better advise. There is a formula somewhere for calculating the correct size dependent on speed you want and if you are ok with going over legal limit of 15-16 mph of assist specified.

 

Re donor bikes I managed to try the Globe and the Pioneer above. The Globe was the better of the two but why are aluminum frames so uncomfortable ? I swear the ride is better on my steel/ti Brompton than either of these full sized bikes.

 

Jerry

The Globe was the better of the two but why are aluminum frames so uncomfortable ?

______________

Fut Coins

 

Exactly why are they ?

 

I ride a steel Brompton and it is way more comfortable than either of these two bikes. I am told steel framed bikes are generally more comfortable to ride.

 

I am now considering getting a s/h 531 frame in my size and building up a bike with a hub gear myself

 

Jerry

Another contender the Dawes Urban Express 7. They also do a three speed version

 

http://www.evanscycles.com/product_image/image/dab/3d8/d1a/126095/large/dawes-urban-express-7-2014-urban-bike.jpg

 

As I said I have been scouring ebay for a older 531 frame which I could build up.

 

Jerry