Moulton conversion

[Elmundopalladio]

Hi there
I'm looking for some expert guidance in the world of bike conversions. I have recently moved job and am finding the public transport options frustrating as it appears to take an abnormal time to travel 6 miles through the city centre. I have a Moulton FX8 sitting in the garage and I was wondering what the best way of converting this to give a pedal assist up hills and so I don't arrive at work too flustered - whilst the full suspension should provide a smoother ride through Edinburgh's cobbles?
I have seen a conversion using a front hub motor (by Jerrysimon several years ago) and also one from Perth Cycles with a bottom bracket motor. I have also seen the ARCC system, but this does come with a hefty price tag for an complete system (around £3k) The round trip every day will be 15 or so miles, so I don't think I will need too large a battery pack (although I am quite large myself at 105Kg so this will obviously have an impact on battery life). I'm not sure how pedal assist works with a front mounted motor - are these designed to push the bike along and you are merely peddling with little force to keep up with the motor speed?
Thanks in advance for any comments.

 

[Deleted member 4366]

I'd use a rear motor, but you need a cassette one to keep your gears. The 328 rpm Q100C should do nicely. 328 rpm is important.

https://bmsbattery.com/ebike-kit/617-q100c-cst-36v350w-rear-driving-e-bike-motor-wheel-ebike-kit.html?search_query=Q100c&results=7

You might have to stretch your rear subframe a bit so that you can add a spacer to the left side of the axle to get the rim central because the motor's spoke flanges are a little off-set.

Use the S06S controller with S-LCD5 display, any PAS and a basic thumb throttle.

For a battery, I'd get Jimmy (Insat International/BGA Reworking or whatever he calls himself these days -someone provide a link please) to make you up a custom 10S2P 36v pack using Samsung 30Q cells, which will give you 6Ah. That should be enough for 15 miles. He can make it any shape you want, like triangular to fit in one of the frame triangles. Make a little 3mm plywood box for it with brackets to fix it to the frame.

That kit will only weigh about 3kg, so you'll hardly notice the weight. It's quite powerful, and has lots of features in the LCD.

The motor will go whenever you pedal and will stop when you stop pedalling. The power is adjustable on-the-go via the lcd thumb switch, or you can get whatever power you want on-demand by using the throttle, which takes precedence over the PAS.

 

[D8ve]

You can't argue with d8veh's advice above

 

[Elmundopalladio]

Thanks - I have done some online looking and the Q100 only seems available as a US import? Do you know of any UK importers (I would prefer some sort of guarantee for a first time build!)
Other builds have used a mid motor - it looks a bit more expensive and fiddly to put together, but has the advantage of being integrated and keeping bike weight low.
Battery pack is a great idea - I was previously measuring the seat post for a bottle type.
Not too sure about stretching the rear subframe - they are pretty strong and too much movement would mis-align the sprocket with the chain. I'll go and measure the rear axel and cassette as it would be preferable to keep the gear ratio (I generally flip between highest and lowest during the commute)

 

[Deleted member 4366]

Stretching the frame is no problem. I've done loads.Yours is steel, which is the easiest of all. We're only talking about 10mm. That's 5mm per side, which is no problem for derailleur gears that move 30mm anyway.

Nobody in the UK sells the Q100C. BMSBattery is reputable. I've placed about 35 orders with them - something like £10,000. Problems are rare. I had one kit where the PAS didn't work, though that might have been settings. The individual items are relatively cheap, so if something were faulty, it wouldn't be the end of the world. A motor on its own is about £100. Even if you add £100 to that kit, it's still good value and perfect for your bike.

 

[5threeone]

Hi there
I'm looking for some expert guidance in the world of bike conversions. I have recently moved job and am finding the public transport options frustrating as it appears to take an abnormal time to travel 6 miles through the city centre. I have a Moulton FX8 sitting in the garage and I was wondering what the best way of converting this to give a pedal assist up hills and so I don't arrive at work too flustered - whilst the full suspension should provide a smoother ride through Edinburgh's cobbles?
I have seen a conversion using a front hub motor (by Jerrysimon several years ago) and also one from Perth Cycles with a bottom bracket motor. I have also seen the ARCC system, but this does come with a hefty price tag for an complete system (around £3k) The round trip every day will be 15 or so miles, so I don't think I will need too large a battery pack (although I am quite large myself at 105Kg so this will obviously have an impact on battery life). I'm not sure how pedal assist works with a front mounted motor - are these designed to push the bike along and you are merely peddling with little force to keep up with the motor speed?
Thanks in advance for any comments.

Not sure how you got on with this intention. Have a look at my (5threeone) post on a similar project. In its embryo stage as of December 15th but aiming to be completed by Dec 21st. I will post then and be glad to pass on my findings. Its completely DIY with a kit.
http://www.pedelecs.co.uk/forum/threads/converting-a-birdy-folder.24828/

 

[orienteer]

Hi there
I'm looking for some expert guidance in the world of bike conversions. I have recently moved job and am finding the public transport options frustrating as it appears to take an abnormal time to travel 6 miles through the city centre. I have a Moulton FX8 sitting in the garage and I was wondering what the best way of converting this to give a pedal assist up hills and so I don't arrive at work too flustered - whilst the full suspension should provide a smoother ride through Edinburgh's cobbles?
I have seen a conversion using a front hub motor (by Jerrysimon several years ago) and also one from Perth Cycles with a bottom bracket motor. I have also seen the ARCC system, but this does come with a hefty price tag for an complete system (around £3k) The round trip every day will be 15 or so miles, so I don't think I will need too large a battery pack (although I am quite large myself at 105Kg so this will obviously have an impact on battery life). I'm not sure how pedal assist works with a front mounted motor - are these designed to push the bike along and you are merely peddling with little force to keep up with the motor speed?
Thanks in advance for any comments.

Had an ARCC system retrofitted to my Moulton ATB tandem conversion, I have only used it in tandem form so far, not solo. It is an excellent, progressive system, unlike some which noticeably cut in and out. Conversion of an existing bike is about £1800. If commuting you can offset this against travel costs.

A new front wheel with a hub motor is fitted, plus a removeable control unit/battery on the steering tube, and a bottom bracket with a sensor.

It uses Bosch a power tool battery and charger. I bought the fast charger, lighter than a spare battery and charges in 30 minutes.

 

[Elmundopalladio]

Had an ARCC system retrofitted to my Moulton ATB tandem conversion, I have only used it in tandem form so far, not solo. It is an excellent, progressive system, unlike some which noticeably cut in and out. Conversion of an existing bike is about £1800. If commuting you can offset this against travel costs.

A new front wheel with a hub motor is fitted, plus a removeable control unit/battery on the steering tube, and a bottom bracket with a sensor.

It uses Bosch a power tool battery and charger. I bought the fast charger, lighter than a spare battery and charges in 30 minutes.

Wow - it looks like a really interesting system, but that is a steep price to pay for it - it would take several years to pay off a the commute!
I did have a look at your tandem and was very impressed - does the central section demount?

 

[orienteer]

Yes, it can be used as the original solo. I use it as my off-road bike since it takes larger section tyres than any other Moulton, and I had a Rohloff 14 speed hub gear fitted when the tandem conversion was built. I have other Moultons for road use.

 

[Elmundopalladio]

Thats an impressive set up - although a rolloff hub coupled with an ARCC system on a Moulton would not last long as my commuter - I would be afraid to use it and I couldn't leave it anywhere in Edinburgh! My FX8 is the rigid frame - I never saw the point of splitting the frame for my usage.

 

[Elmundopalladio]

Stretching the frame is no problem. I've done loads.Yours is steel, which is the easiest of all. We're only talking about 10mm. That's 5mm per side, which is no problem for derailleur gears that move 30mm anyway.

Nobody in the UK sells the Q100C. BMSBattery is reputable. I've placed about 35 orders with them - something like £10,000. Problems are rare. I had one kit where the PAS didn't work, though that might have been settings. The individual items are relatively cheap, so if something were faulty, it wouldn't be the end of the world. A motor on its own is about £100. Even if you add £100 to that kit, it's still good value and perfect for your bike.

I'm still swithering between a rear hub or a mid drive (i'm not going to start messing with the front forks due to the unique suspension system). The torque sensors on a mid drive are more likely to suit my riding style and I have some long hills on my route to work. They are a fair bit more expensive though.

The Q100 looks like a more affordable option. I'm not sure how easy it will be to pull out the wheel to fix punctures (the bane of my life - I've gone for the most bullet proof tyres with goo inside, but I suspect my bulk coupled with high pressures and the liberal scattering of sharp things in Edinburgh means this is a loosing battle!)

How does the peddle assist work - do the cadence sensors kick in after a rotation and then adjusts the motor accordingly? Also - does the drive power just the wheel and peddling gives an extra assist?

Thanks