My New Build

[Waspy]

Thank you Tony.

Saneagle gave me some guidance on label making.

 

[Tony1951]

I'd need mud guards on it mind.

 

[Waspy]

I'd need mud guards on it mind.

The thought has crossed my mind.

It would make a change from buying nuts and bolts

 

[Peter.Bridge]

I've tried the short plastic ones and the full mudguards - I wasn't sure about the short ones, but they seem to do a job. I don't really ride in very bad weather though

 

[Tony1951]

I've tried the short plastic ones and the full mudguards - I wasn't sure about the short ones, but they seem to do a job. I don't really ride in very bad weather though

View attachment 64420View attachment 64421

That's a nice build too.

 

[saneagle]

How do you find the front wheel drive?

I built a Brompton in 2015 using a Q85 motor, which Is a bit smaller, but quite strong on torque. IIRC, I ran it at 36v and 12A. On the flat. you don't really notice the motor apart from the slightly more noise compared with a rear motor. The Brompton's long wheelbase and low profile helps a lot to eliminate any handling differences. Those Crosscities would be similar. The one thing you can't get away from is the lack of traction on steep hills. When I took it up my 14% (measured) test hill, I could get up without pedalling, despite the relatively low power, but there was a small amount of slipping and skipping on the very good tarmac surface. That's because of the huge torque you get from a motor in a 16" wheel. If the surface is compromised in any way, like gravel or mud, on a steep hill, it'll slip a lot. So, you get the advantage of the extra torque, but the disadvantage of less traction. the traction is only a problem on the steepest hills and ones with bad surface.



The effect of small wheels on torque is very profound, as you've probably noticed on your folding bike, where the very low power is still enough to get you up fairly steep hills, though slowly. The Brompton was doing about 4 mph up that 14% test hill, and quite happy to maintain that speed - when it wasn't slipping. It had a Marathon Plus on the front, which is not noted for good grip, so that might have been a contributing factor. If you had a motor giving 40Nm in a 29" wheel, it would give nearly 80Nm in a 16" one using the same battery and controller. Now that we're all sticking to 15 mph, heavyweights, like me, can get away with much less power by using a bike with small wheels, as long as you don't need to go too far. That's why I'm building a compact bike for local journeys.

 

[Waspy]

That's a nice build too.

Peter's builds have been the inspiration for my latest conversion.

 

[Waspy]

That's why I'm building a compact bike for local journeys.

How's that progressing by the way?

 

[saneagle]

How's that progressing by the way?

I now have nearly everything I need for the project. I'm struggling to get the motor in the frame because the frame is so stiff. Every time I tap one side down, the other side comes up, and if I bolt one side down, the other side won't go down. The drop-outs must be narrower on the side closer to the mudguard than the side closer to the ground to cause that. I've been feeling a bit rough the last few days. Between that and this problem, it demotivated me a bit. I will sort it out, but I need to wait until I feel a bit better.

 

[Tony1951]

I now have nearly everything I need for the project. I'm struggling to get the motor in the frame because the frame is so stiff. Every time I tap one side down, the other side comes up, and if I bolt one side down, the other side won't go down. The drop-outs must be narrower on the side closer to the mudguard than the side closer to the ground to cause that. I've been feeling a bit rough the last few days. Between that and this problem, it demotivated me a bit. I will sort it out, but I need to wait until I feel a bit better.

Sorry to hear you are feeling rough. Get well soon. We are waiting to see the new bike.

 

[Waspy]

I now have nearly everything I need for the project. I'm struggling to get the motor in the frame because the frame is so stiff. Every time I tap one side down, the other side comes up, and if I bolt one side down, the other side won't go down. The drop-outs must be narrower on the side closer to the mudguard than the side closer to the ground to cause that. I've been feeling a bit rough the last few days. Between that and this problem, it demotivated me a bit. I will sort it out, but I need to wait until I feel a bit better.

Get well soon. Good idea to take a rest for a while. Most problems seem easier after ignoring them for a few days.

 

[saneagle]

Get well soon. Good idea to take a rest for a while. Most problems seem easier after ignoring them for a few days.

One of my rules for life: All problems go away after a time.

 

[Tony1951]

I built a Brompton in 2015 using a Q85 motor, which Is a bit smaller, but quite strong on torque. IIRC, I ran it at 36v and 12A. On the flat. you don't really notice the motor apart from the slightly more noise compared with a rear motor. The Brompton's long wheelbase and low profile helps a lot to eliminate any handling differences. Those Crosscities would be similar. The one thing you can't get away from is the lack of traction on steep hills. When I took it up my 14% (measured) test hill, I could get up without pedalling, despite the relatively low power, but there was a small amount of slipping and skipping on the very good tarmac surface. That's because of the huge torque you get from a motor in a 16" wheel. If the surface is compromised in any way, like gravel or mud, on a steep hill, it'll slip a lot. So, you get the advantage of the extra torque, but the disadvantage of less traction. the traction is only a problem on the steepest hills and ones with bad surface.

View attachment 64422

The effect of small wheels on torque is very profound, as you've probably noticed on your folding bike, where the very low power is still enough to get you up fairly steep hills, though slowly. The Brompton was doing about 4 mph up that 14% test hill, and quite happy to maintain that speed - when it wasn't slipping. It had a Marathon Plus on the front, which is not noted for good grip, so that might have been a contributing factor. If you had a motor giving 40Nm in a 29" wheel, it would give nearly 80Nm in a 16" one using the same battery and controller. Now that we're all sticking to 15 mph, heavyweights, like me, can get away with much less power by using a bike with small wheels, as long as you don't need to go too far. That's why I'm building a compact bike for local journeys.

This tempts me to start interfering with my Brompton. I like the way you mounted the battery.

AKM85 with a speed of 328 rpm, sounds about right. I also like the way Waspy mounted his battery in that camera bag thing. Looks neat and tidy.

The only problem is - I already have more bikes than I know what to do with.