16" folder electrification

[alban]

Hi Y'All - some help appreciated. have read around but can't quite find the info I want.
Embarking on what I hope will be a simple motorisation of a cheapo 16" alloy folder I already have in mind.
Why DIY? So I get more what I want for a decent price. Cheaper bikes tend to be 24V only.

Requirements
A folder that is as small as poss without costing a fortune in the first place i.e. not a Brompton etc as it's for occasional use but needs to be shipped abroad.
Able to do tracks as well as roads, but not too bumpy.
Able to do all of the work of shifting 105Kgs up inclines however slowly. Shortish rides.
Bike Compact Folding Bike.
16" to reduce size of package (not mine ! - but could have that effect!) - off-road may not be brilliant but only going slowly so doable d'you think? Alloy frame but steel forks so bendable. Front susp necessary tho'?
Motor kit
Sooo - thinking of a 36V kit from BMSbatt as they sent me stuff quickly recently and I have 36V batts. How long do you have to wait normally as I need it by 4 weeks time!
Front wheel as easier all round? Bike sellers do a front bag to stuff a batt in - so not too battered by lack of front susp?
Which motor? Bafang BPM too heavy? Q100 or 85 250W? - is that difference only the dropout width? 201 or 368rpm? I want climbing not speed (OK with top of 8mph!) so 201? They supply KU63 controller I think. I read d8veh saying some probs with that controller and 368rpm one?
Wheel likely to be compatible as Chinese? Torque arms too.
Any other probs?
I defer to experience as I just don't want hassle and fettling more than a wee bit. Vain hope.

 

[jerrysimon]

Hmm mees thinks you seek the holy grail

Some things to think about:

1. Dropout width if you go with a front motor most 16" wheeled bikes are likely to restrict you to 80mm wide motors to simplify fitting. These will mean you need to assist more though I guess you could look at rear wheel motor options.
2. Small wheels and comfort on bumpy surfaces just don't go together. Suspension or Big Apple tyres (which are only available in the smaller 305 16" size) will help.
3. Many small wheeled cheap bikes really have bad geometry and are not much good/comfortable to ride more than a couple of miles. Therefore not much point in adding e-assist.
4. Weight on the front (a bag) except if it is frame mounted will effect steering badly.
5. Its really hard to get gearing right on a small wheeled bike.

I don't mean to sound negative but I have tried and converted quite a few small wheeled bikes. If you require portability the only answer is a Brompton and if its light you require as well then its a Brompton Ti

Now if you were prepared to go up to 20" wheels I could give you more options.

PS the bike you linked to does not look too bad but at that weight with assistance added its going to be heavy.

Regards

Jerry

 

[RobF]

The bike you linked to is a cheap, and almost certainly, nasty device.

The only thing I would convert it to is a scrap bale.

Sixteen inch wheels are not ideal off-road - I have a Brompton, the best folder there is, but it's not much cop off-road, so nothing else will be.

Add the cost of the kit to the 'bike' you are thinking of converting, and I reckon it will be cheaper and better to get something ready made.

You say you need the bike within four weeks, conversion projects are notorious for hiccups which is another reason not to do it.

Hatti at Woosh has several ready made folders, including a crank drive which is likely to be better on hills.

All run on 20" wheels, which will handle light off-road no bother at all.

Electric Bikes | Woosh e-bikes | electric bicycles sales & hire

 

[Old_Dave]

If your reallllllllllyyyyyyyyyyy sure you want 16", I've got a couple of 20" folders and some times I think even they are a bit small when the going gets tough.

But you know what your use is going to be.. so you may well be right

Q100 with either KU63 or the KU65 with control / display is a great choice, available as front or rear (I wouldn't get the 85)

Front is easier to fit (although due to the small size of the wheels back would be less skippy)

I'd be inclined to go for the 368 due to the small wheel size.

But then RobF makes a good point

 

[flecc]

I agree with what the others have said above about the need for 20" wheels as a minimum for off-road. However, the bike you linked to does have one feature better than most of the cheap 16" wheel folders, it has a decent wheelbase length and good saddle-to-handlebars separation. Far too many folders and especially the 16" wheel ones have cramped proportions and over-the-rear-wheel seating which makes them wheelie prone when climbing and with steering too light on poor surfaces.

Whatever you chose is going to be compromised though, either bigger and heavier than you wanted or very poor off-road and limited in other respects.

 

[Deleted member 4366]

KU65 is normally better than KU63 because you get variable PAS, but with 16" wheels, it'll be slow or slower.

A 201 rpm motor will be very slow with 16" wheels. Top speed on the flat will be 11 mph, but hill-climbing speed will be only about 5mph or less - maybe as low as 3mph. For a 20" wheeled bike, the speeds would be 14mph and 6mph.

10 to 14 days is the normal delivery time.

 

[RoadieRoger]

Have a look at one of Hatti`s Folders . The Woosh Gale has plenty of volts and capacity . My brother has just bought the Woosh Sant Ana and it is fast , powerful and quiet . It has the same electrics as the Gale .

 

[alban]

Thanks chaps. OK 20" wheels then...!
What about GNG kit for good climbing at slow speeds and doesn't matter to me if top speed not great? On a similar 20" bike, say Explorer Folding Bike. Have read about Old-Dave's and d8veh's conversions. What likely problems with fitting (BB width 68mm etc), what kit (prob needs to be 250W as taking it to EU and don't want to fall foul of gendarmeria(?) - and what about the throttle and PAS required? - only brushless version for PAS? - I can't use Speedict) and is it really going to be better at climbing with 110KGs lump onboard in the real world than a hub?
Am I likely to get lucky and it be straightforward?!
Thanks

 

[Old_Dave]

If your not to far away... pop up and have a try, got a 20" brushed gng to 3 speed hub, and a 20" rear hub Q100.

Am I likely to get lucky and it be straightforward?!

That only comes on about the 3rd conversion, lol.. it takes 2 to find out how not to do it

 

[Deleted member 4366]

The GNG kits are not going to be strictly legal under EU law. This is the one I'd get if you want to take a chance. It has throttle only, which is the problem, but would they be bothered as long as you're pedalling?

This kit gives you the chance for a modified larger chain-wheel for more sensible pedal speed. These kits are very easy to fit, but look at the photos and check that whatever bike you get has similar frame arrangement so that the main bracket fits. Don't forget to ask for 36v version at the same price, and the cheaper air-mail shipping comes in about a week.

24V 250W middrive

 

[jackhandy]

I fitted the "new" 250w. brushed motor kit to my bouncer a while back, which is the one d8veh linked, except mine is 36v.

It's quite noisy, having steel gears & not particularly powerful. When I eventually got my speedict to report some sensible data,I found it was topping-out at 13 amps, although the controller seems to be marked as 16 amps (in Chinese!)

A bit of shunt soldering now has it reaching 17.5 amps. I got carried away with adding a bit too much solder & it reached 19.5 amps just before the 25 amps battery fuse popped

I appreciate you're looking at the brushless kit, but thought my experiences might be of some assistance, anyway.

Whether the gng kits are particularly suited to a wet climate remains to be seen.

Btw: This one comes with a 44t chainwheel

 

[jerrysimon]

These look quite good for a 20" folder. Pretty much a clone Dahon but at a great price. No weights ?

Dunlop Twist 20 inch Folding Bike - SportsDirect.com

They also do a 16" 305 wheeled one again very Dahon looking though the reach looks stunted.

Jerry