Contemplating...

[thirteen]

Hi all, from a 51 year old newbie to the scene. This is a bit of a non-committed introduction.

I used to be a regular cyclist, bit of mountain biking, 30 mile round trip commute 2-3 times a week, 6 months of the year, London to Brighton ride ever year, that kind of thing.

10 years ago I had a knee injury. Recovery from that affected my "good" knee leaving me with pain in both if I over-exert myself. Over the following 10 years I did on odd occasions have spurts of activity but ultimately it fizzled out. I sold my MTBs, but kept my old Brompton M3 and built a single speed with a 2.6 ratio from an early 90s Raleigh steel frame MTB and other parts that folk were throwing away.

I have read the excellent articles on this community site and browsed the forum. I have also test ridden a Haibike MTB and a Kalkhoff Dutch-style 8-speeder. Both were fantastic but a bit too rich for me. Perversely I'd like to take a hands on approach if I'm going to go down the e-bike road. Hence I'm thinking about converting my ratty single speeder.

"Why?" you may ask. For one I have a bit of a affinity with it. I like the frame size and how it fits me. I like the fact that it is low-tech and doesn't need constant fettling. It also doesn't look worth nicking. Mostly though, because I'm perpetually poor and using my current bike would hopefully keep any potential conversion costs down.

What I was thinking was maybe a simple front hub motor with a thumb throttle, and a rear rack mounted battery. I already have a suitable rack. Does that sound feasible? thanks in advance for any advice, even if it's just "Don't be so stupid!"

 

[hoppy]

Hi all, from a 51 year old newbie to the scene. This is a bit of a non-committed introduction.

I used to be a regular cyclist, bit of mountain biking, 30 mile round trip commute 2-3 times a week, 6 months of the year, London to Brighton ride ever year, that kind of thing.

10 years ago I had a knee injury. Recovery from that affected my "good" knee leaving me with pain in both if I over-exert myself. Over the following 10 years I did on odd occasions have spurts of activity but ultimately it fizzled out. I sold my MTBs, but kept my old Brompton M3 and built a single speed with a 2.6 ratio from an early 90s Raleigh steel frame MTB and other parts that folk were throwing away.

I have read the excellent articles on this community site and browsed the forum. I have also test ridden a Haibike MTB and a Kalkhoff Dutch-style 8-speeder. Both were fantastic but a bit too rich for me. Perversely I'd like to take a hands on approach if I'm going to go down the e-bike road. Hence I'm thinking about converting my ratty single speeder.

"Why?" you may ask. For one I have a bit of a affinity with it. I like the frame size and how it fits me. I like the fact that it is low-tech and doesn't need constant fettling. It also doesn't look worth nicking. Mostly though, because I'm perpetually poor and using my current bike would hopefully keep any potential conversion costs down.

What I was thinking was maybe a simple front hub motor with a thumb throttle, and a rear rack mounted battery. I already have a suitable rack. Does that sound feasible? thanks in advance for any advice, even if it's just "Don't be so stupid!"

Not stupid at all! On the contrary, easily and cheaply achieved, especially if you buy direct from China. Try the BMS Battery site. Best wishes. Throttles are great with bad knees as you can finely adjust the power to suit how much you can pedal. Some people don't seem to understand this!

 

[Kudoscycles]

Thirteen....interesting nickname!.... Whilst I respect your wish to DIY,it can be almost as cheap to buy a ready built bike,such is the crazy pricing structure of parts coming out of China and import duty additions.
Might I suggest a trip to the London Electric Bike Company at Hampton Wick,if only to go along with a camera and get ideas. They have a bike named the Vita Uno 26 priced at £695.00 ,that is really good value,also some ex demo bikes
KudosDave

 

[thirteen]

That's two very good suggestions that I will check out. Thank you hoppy and KudosDave.

 

[NZgeek]

If you're into fiddling, a kit can be a cool way to build a bike. Start simple, but work up to a better level of componentry as you go.

My first build is a 36V Direct Drive 500W hub, initially in the rear wheel, but I machined the shaft down and fitted it to the front. I got the kit without a battery from Vpower.hk, and a Golden Motor battery from a local supplier here in NZ.

I started with a 35 GBP 90's Diamondback, which was a pretty basic bike back in the day, but a solid thing too. I've since changed practically everything on it (including the paint!) and it's probably only cost 3X what a premade bike would have . Though to be fair, I don't do anything too cheaply, and have some goodies on it, like a Nuvinci hub, Schwalbe marathons etc. In reality, it's probably a better bike than the prebuilt one would be for the same money (here in NZ anyway!), but it's also setup the way I want it. It's probably not a spractical as a pre-built, because I had to make a mid mount battery bracket and use up the triangle space to carry it, rather than having it behind the seat or similar.

I wasn't sure if I'd use it (hence the cheap initial build) as I have NEVER commuted by cycle until last year, but I use it most days now. Initially I set it up just to see that I'd use it, then once I discovered I enjoyed the cycle commute, I replaced all the cheap nasty parts that were wearing out really fast!

I actually enjoy it so much now, that I'm hacking, cutting, bending and brazing myself a long tail cargo bike that I can strap the kiddies onto the back of! It's 450mm longer than a "standard" bike, and will have a bafang mid drive to start with.

 

[thirteen]

Thanks NZGeek. Actually that's reminding me of another reason why I'd favour using my existing single speeder. Although it is made from 90% used/discarded parts they were all half-decent at one time (early 90s Shimano XT etc).

I know that the single speed is a bit perverse, especially for someone with weak knees but in terms of regular bicycles it's what I prefer, heyho.

I'm OK with bike building after many years, it's just the electric side of it I have a steep learning curve to address. For that reason I won't rule out something like that Vita Uno 26, although I looked at it online and immediately started mentally stripping bits off it.

 

[Deleted member 4366]

What kit you need depends on your weight and the steepnwss of the hills you encounter. I guess that it must be flat where you are to use single speed.

 

[thirteen]

What kit you need depends on your weight and the steepnwss of the hills you encounter. I guess that it must be flat where you are to use single speed.

Not entirely flat, but not exactly Ditchling Beacon either. I'm 80-82kg depending upon how close it is to Christmas.

 

[Deleted member 4366]

You can probably get away with a nice Q100 kit from BMSBattery.com or the equivalent from Greenbikekit.com.
The Q100 is 201 rpm for about 15mph . The Q100H from BMSB is 260 rpm for about 19 mph. They're both on the road speeds. The Q100H is a pick-and-mix kit, so you can get a nice LCD and other stuff.

 

[thirteen]

Thanks for that. Excuse my ignorance but what would I notice as the performance difference between the Q100 and Q100H?

 

[berkobennie]

I had to go down the route of shortening crank arms, movement was so restricted, two replacement knees later and I have a full range of (painless) movement, might be an upgrade you factor in for the future!

 

[thirteen]

If it ain't broke (yet), don't fix it, bennie. Point taken. Hopefully I'll avoid that but ya never know. Cheers!

 

[thirteen]

Thirteen....interesting nickname!.... Whilst I respect your wish to DIY,it can be almost as cheap to buy a ready built bike,such is the crazy pricing structure of parts coming out of China and import duty additions.
Might I suggest a trip to the London Electric Bike Company at Hampton Wick,if only to go along with a camera and get ideas. They have a bike named the Vita Uno 26 priced at £695.00 ,that is really good value,also some ex demo bikes
KudosDave

This stuck in my mind and with other projects to complete on the outside of the house this Summer I figured I'd save valuable time by buying a Vita Uno 26...only to find that the price has gone up by 20% in the past couple of weeks and is now £835.

So, I'm probably going to go the build route but will wait until the weather is cooler. Hills aren't so much my issue these days as strong winds, something we get a lot on the coast.

Until then I'll continue cycling unassisted, reading on this forum and learning more. Thanks for your help so far and I'll be back.

 

[trex]

..
What I was thinking was maybe a simple front hub motor with a thumb throttle, and a rear rack mounted battery. I already have a suitable rack. Does that sound feasible? thanks in advance for any advice, even if it's just "Don't be so stupid!"

You may have described the £850 Big Bear:
http://wooshbikes.co.uk/?bigbear

 

[Cyclezee]

Also for £850, The eZee Sprint Primo GTS
http://www.cyclezee.com/ezee-sprint-primo.html

 

[Deleted member 4366]

Thanks for that. Excuse my ignorance but what would I notice as the performance difference between the Q100 and Q100H?

The Q100 maxes out at about 15mph, the Q100H at 19mph, so when you're pedalling along at 15mph, you get no torque from the Q100, while as the Q100H is right in it's sweet spot. You have to decide how fast you want to go.

The Q100H is supposed to be more powerful, so should handle more current without overheating. The Q100 can go up to about 18 amps, so the Q100H should be able to manage 20A, which will give it even more torque, which might be useful for a single-speed bike.

 

[thirteen]

Funnily enough, when browsing off-the-shelf bikes those two have caught my eye. With the price hike of the Vita Uno 26 I wouldn't even consider it against those two.

However, the crux of the matter is that my decision was based on a complete bike for under £700 versus a self-build. At under £700 it was touch and go but time constraints tempted me to buy.

At £850-ish it is out of the question. The self-build wins, even though I haven't got time at the moment.

Thanks d8veh for that explanation. Used to riding dumbed-down simple bikes like my single speeder I'd have said that I rarely reach 15mph if ever. However after cycling with my Daughter she assures me that I do, frequently and for extended durations.

So, perhaps the Q100H kit is the way to go.

Thanks again to everyone who has responded.

 

[trex]

if you've decided to convert your bike, check out the £330 CD kit:

http://wooshbikes.co.uk/?cdkit

 

[Deleted member 4366]

Trex, a crank-drive is no good for single-speed!

 

[trex]

true. Apologies, 13.