road bike frames for electric conversion

[hod]

Hello,

I'm interested in building a custom electric bicycle.
Right now, I'm just looking at frames.

I want to use a road bike frame or something similar.
Basically, i am after a certain aesthetic that uses a
flat top bar like a road bike, but thicker.

The dilemma is finding a frame like this that meets
the strength requirements and rear dropout width
for a direct drive rear electric motor installation.

The frame on this Grace One bicycle as seen in
the attachment is along the lines of what I'm looking for.
Would you have any idea where i can find a frame
like this that will lend itself to an electric bike?

If anyone can advise me on this, it would be
much appreciated.

Thanks,
N

 

[Alan Quay]

Perhaps I'm missing something, but it sounds like you are looking for a hard tail mountain bike?

 

[Geebee]

Try your local Xmart style shop, the thick frames seem popular on BSO's you could use the frame and junk anything on it that was to low end.
Can I ask why you want to use a direct drive hub?

 

[hod]

Perhaps I'm missing something, but it sounds like you are looking for a hard tail mountain bike?

Mike,

Thanks for your input. Certainly a hard-tail mountain bike could satisfy me. However, it would need to look the way i described. I don't care about categorization. All the mountain bikes i've looked at thus don't have the form i'm looking for.

Its difficult to explain what i have in my mind's eye. The closest example is the image of the Grace "One" i attached. I'm not finding any frames that resemble it. I like road bike-esque frames, but the rear drops are too narrow for a direct drive motor and too weak for the torque.

I know I'm being very particular here,
but i know what i want.

Thanks.

-N

 

[Clockwise]

I wouldn't assume a bike is stronger as it has thicker tubes. Often it means the tubes are aluminum which isn't as strong, thinner tubes will be steel/cromo or titanium, anything overly curved is normally carbon fibre.

It really depends on your intended uses. I wouldn't advise an ebike made from a road bike as it will only have clearances for slim tyres and with the extra weight of battery and motor it will just be a nightmare to keep it going, if you go with a small battery to offset how flimsy some road parts are then you won't get enough miles from the battery to justify carrying it. Also with many road bikes 15mph is really easy to reach so the motor will be off lots, on my single speed I ride 46/18(for most it will be top gear on the front and about half way on the back) and at 80 cadence with not much effort I'm going 17mph.

I would be really careful too, lots of the ebikes with "that look" are marketed to say they can do huge jumps at crazy speeds and stuff like a motocross bike but when it comes down to it they aren't motocross bikes.

 

[hod]

Try your local Xmart style shop, the thick frames seem popular on BSO's you could use the frame and junk anything on it that was to low end.
Can I ask why you want to use a direct drive hub?

Geebee,

Thanks for your help. That sounds like a good idea or someone, but I'm not gonna be utilizing any bicycle shaped objects from Walmart.

A direct drive hub will offer me the 40 mph top speed I'm looking for without any bulky installations.

 

[hod]

I wouldn't assume a bike is stronger as it has thicker tubes. Often it means the tubes are aluminum which isn't as strong, thinner tubes will be steel/cromo or titanium, anything overly curved is normally carbon fibre.

It really depends on your intended uses. I wouldn't advise an ebike made from a road bike as it will only have clearances for slim tyres and with the extra weight of battery and motor it will just be a nightmare to keep it going, if you go with a small battery to offset how flimsy some road parts are then you won't get enough miles from the battery to justify carrying it. Also with many road bikes 15mph is really easy to reach so the motor will be off lots, on my single speed I ride 46/18(for most it will be top gear on the front and about half way on the back) and at 80 cadence with not much effort I'm going 17mph.

I would be really careful too, lots of the ebikes with "that look" are marketed to say they can do huge jumps at crazy speeds and stuff like a motocross bike but when it comes down to it they aren't motocross bikes.

Clockwise,

Those are some good points. I'll keep that in mind.

The appeal of the Grace "One" and other e bikes has zero to do with any desire to jump or go off-road. I'm looking for a modest electric bike to use casually around town. I just have a preference about the way the frame looks.

-N

 

[trex]

a road bike with short wheel base?

Royal-H:

Grace 1:

 

[Alan Quay]

Mike,

Thanks for your input. Certainly a hard-tail mountain bike could satisfy me. However, it would need to look the way i described. I don't care about categorization. All the mountain bikes i've looked at thus don't have the form i'm looking for.

Its difficult to explain what i have in my mind's eye. The closest example is the image of the Grace "One" i attached. I'm not finding any frames that resemble it. I like road bike-esque frames, but the rear drops are too narrow for a direct drive motor and too weak for the torque.

I know I'm being very particular here,
but i know what i want.

Thanks.

-N

By 'Flat top bar' do you mean horizontal?? If so, many older steel MTB frames are more like that, especially Claud Butlers:

If you could find one of these in a 23" frame, would that be closer? With a respray and thick tires?

 

[sheffieldmike]

Hi,
Sorry to but in, I have the Claud Butler shown. If I undertand right, this frame would be strong enough for a rear hub, better than a big alloy frame? ta mike

 

[Deleted member 4366]

It should be very easy to fit a motor in a steel-framed road bike. You don't have to worry about the width because a simple heave-ho on the frame should adjust it to whatever you want. There's not a lot of meat around the drop-outs, so I wouldn't go too high on the power unless you can find someway of strengthening it. The other problem you have to overcome is the brakes. If you wanted to fit a sizeable direct drive motor, you'd need disc brakes.

 

[Alan Quay]

Hi,
Sorry to but in, I have the Claud Butler shown. If I undertand right, this frame would be strong enough for a rear hub, better than a big alloy frame? ta mike

Yes, I would have thought it would make a really good donor bike, although as D8veh says above about the road bike, brakes are important.

My own personal minimum is V-Brakes. That Butler looks to have cantilevers. If it was me, I'd try to upgrade them to a set of quality V-brakes (Tektro as an example).

Better than a big alloy frame? I don't know, its all about personal preference. I suspect it'll be heavier, but that may not be important to you.

 

[sheffieldmike]

Thanks for advice, I will try it. I will sort the brakes out even though I am not a speed merchant, I just need more help with hills. I bought the bike at a car boot, the decalls had been taken off. It looks like a 531 label on your frame in your pic? The drop outs do look a bit thin but then looking at the big alloy frame I have, they do also.
Just tried the hub on the bench and another puzzle to work out? The wheel turns without the throttle connected. When I connect it and twist the throttle it stops?

 

[D8ve]

40 mph about town? You need a strong frame and brakes.
And me off the thread

 

[Alan Quay]

Thanks for advice, I will try it. I will sort the brakes out even though I am not a speed merchant, I just need more help with hills. I bought the bike at a car boot, the decalls had been taken off. It looks like a 531 label on your frame in your pic? The drop outs do look a bit thin but then looking at the big alloy frame I have, they do also.
Just tried the hub on the bench and another puzzle to work out? The wheel turns without the throttle connected. When I connect it and twist the throttle it stops?

Sheffield Mike,

Sorry, its not my bike, just a pic from the web.

Its not a big deal, but I don't want to hijack this thread, so would you mind posting a new thread about your build please. I'm sure you will get plenty of help.

Thanks

 

[pn_day]

Hod, if you want a road frame I'd recommend a cyclocross - space for bigger tyres than a standard road frame.
I've just finished my build using a Surly Cross check and managed to squeeze 700c 42 wide tyres plus mudguards in. With no suspension bigger tyres are very useful for a comfortable ride considering all the extra weight you'll be carrying.
Regards
Phil

 

[sheffieldmike]

ok thanks