What makes an efficient on road e-bike?

[coops]

Coops - This project of yours is contagious...

Hehehe! Its infectious, definitely! But its not mine, nor a project - yet - John! More just a "radical" Torq radical "idea"! And the idea/concept itself is flecc's: the "Torq radical principle" if you like (correct that if its wrong flecc! )

Yes, I thought the same, I really do seem to have kicked off a movement. Wouldn't it be good if an enterprising frame maker put on the market a frame with rear of seat tube space for a battery and a choice of forks, standard or wide in both rigid and sprung formats.

Yes, it would be great for skilled workers and "tinkerers" alike - I had the same idea about the frames - I guess most companies would prefer to keep mods & improvements "in-house" if you like, but if the parts you describe were available separately, great! Pedelecs brand, what do you think, eh?!

I appreciate that it could be seen as an unnecessary extra expense just to modify an already "premium" price bike, shall we say, but for the cost of the mod, if I've got it right, you might have nearly all the parts to kit out another bike - except for a battery & fixture, but I've an idea for that too:

Personally, I'd quite like to build a sort of short-range "stealth" bike (call it an urban shopper ) which could, but not necessarily, combine aspects of both the Q & T mods i.e. find a suitable 20-24" bike to fit the replaced motor to, either in front forks (if they are wide & strong enough, and accepting the implications of front mounting - could use suspension, if wanted) or rear-mount like the T bike, and an "experimental" low weight, capacity & removeable lithium battery of, say, around 1kg for every ~100Wh or so, ~8miles at 15mph: handy for those short shopping trips you don't want to get the car (or the commuting bike ) out for, good low load carrying capacity for carrying it home & with mini battery removed while shopping, rather inconspicuous & "ordinary/boring" looking so good for security too .

EDIT: These are all just ideas, so feel free to add or criticise, since I don't have the knowhow to plan nor the skill to undertake any major project like this, so if it was ever going to happen, it could only be by a sort of collaboration I guess .

Good design principles should always be learned from & imitated, eh flecc?! I openly say all these ideas are inspired by & derived from your projects and your experiences so helpfully posted here - hope you don't mind; I just hope any projects which follow on from yours do them justice, and I'm definitely willing to improve or scrap any ideas for new ones, based on advice!

I'd have to rename the "urban shopper" though... any suggestions? Must be converse e.g. the "marathon racer" (clearly does neither, race nor marathon distances!)

P.S. Sorry John, your threads sort of mutating a bit! If the ideas seem feasible and are not inadvisable, then I could start a new thread on this new modding "movement", or at least the spin-off (i.e. the "marathon racer") .

Stuart.

 

[Ian]

Ian

I think I was thinking of connecting them the other way, which would make each bank of 5 roughly 6 inches wide?

I've seen too many Ezee batteries in which the cells are end to end, I was forgeting there are other ways.

 

[Ian]

I'd have to rename the "urban shopper" though... any suggestions?

Ask Leonardo to come up with a snazzy Italian name

 

[flecc]

And the idea/concept itself is flecc's: but I've an idea for that too:

Personally, I'd quite like to build a sort of short-range "stealth" bike (call it an urban shopper ) which could, but not necessarily, combine aspects of both the Q & T mods i.e. find a suitable 20-24" bike to fit the replaced motor to,

Stuart.

At the time of conceiving the Q bike, I looked around for 22" rims, since there was the odd Chinese e-bike marketed with those, but none available, and tyres for that size were too restricted. It was possible to squeeze the 22" into the Quando II frame and that would have been a similar compromise, giving a touch more speed at the cost of a little of that immense hill climb capability. As it turned out I'm happy I didn't succeed, since the Quando spins up to 18 or more mph on a fully charged battery, plenty fast enough for an all purpose bike.

However, the Quando motor would be great in a 24" wheel, easily climbing as well as most mid power e-bikes and with 20 mph as well. Since most Quandos sold at around £745 at most and they've been out for well over three years, there are second hand ones about, and one member, Cocoabeans, bought one recently. Also, Team Hybrid had some Quando motors in stock a few months back and may still have some.
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[flecc]

Ask Leonardo to come up with a snazzy Italian name

How about this Italian name for it: "Whatamistakatomaka"

(With apologies to the cast of 'allo 'allo) (and Stuart!)
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[coops]

However, the Quando motor would be great in a 24" wheel, easily climbing as well as most mid power e-bikes and with 20 mph as well. Since most Quandos sold at around £745 at most and they've been out for well over three years, there are second hand ones about

I've asked the same question on the T-bike thread flecc, so please excuse the repetition, (and the engineering ignorance ) but which would you say is less technically difficult: adding a freewheel to the already rear-mounted Quando motor, or moving the Torq motor to the rear and adding a freewheel to that, and so which is easier to achieve in that respect: the Q freewheel motor, or rear-fitted freewheel T motor in, say, a suitable 20-24" frame?

How about this Italian name for it: "Whatamistakatomaka"

Hehehe! I like it! (I think I saw that, the other day!) (but what are you trying to say? I hope that's a (at least partially) "converse" name! )

P.S. Might have to lengthen the frame/downtube - just to fit the name on!

 

[JohnInStockie]

bespoke frame builders

Just been doing a bit of surfing, and it seems that there are indeed a number of bespoke frame builders that will build it whatever way you want for reasonable prices too.

The first I saw was this and this

So if this 'project' for an efficient ebike, that is designed not to lose any rider input but remain relatively comfortable (sorry Coops those sus-forks have to go ) then one could design the frame based on expert advice perhaps?

John

 

[coops]

sorry Coops those sus-forks have to go

That's ok John, that bit was just a suggested "leisure/comfort/utility" spin-off idea anyway... .

 

[flecc]

The Torq motor to the rear is more difficult in some ways, since it means turning a spigot with steps for the DMR hub end and the motor end plate to ensure absolute centering when attaching. Also grinding off the steel side plate end is a dangerous operation and must be accurately done so the motor bearing is brought into the motor just enough, a fraction too far and you'll need a new motor.

Using an angle grinder to that degree of accuracy is tricky, and I did it by using the Torq as a capstan lathe, the bike upside down with the motor running flat out while I ground against it with the angle grinder. It was the stuff of manufacturer's nightmares, but it gave me an accurately flat enough face to attach to. The DMR hub is a whopping £59 odd, and you need to be able to do tricky things with a lathe, both for adapting the hub and to make the support sleeve for the weak motor spindle. There's the short spindle problem too.

Using the Quando motor means getting someone to make the thread adaptor. I used Highpath Engineering as they are cycle stuff specialists. They have to buy a BMX hub as a template and work from that. Once made, you'll still need a lathe and have to do a delicate bit of paring 2 mm from the inner internal thread and 2 mm from the outer external thread for it all to assemble. The alloy thread adaptor is a job to "run in" on the steel hub thread as well, and you could get an irrevocable lock up part way on when assembling. The cost will be about £80 including the BMX hub charged to you. You still need to make the spindle support adaptor but at least the spindle is a bit longer on the Quando version.

As you will have gathered, neither is to be attempted lightheartedly, and if you don't have a lot of engineering experience of some relevance, probably not advisable. Definitely not for the average DIYer.
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[coops]

I think I'd struggle to mod an existing bike, John is your idea to really design & build an ebike from start to finish? do you really think that's do-able?! (I'm open to persuasion, & no harm brainstorming )

Which type of motor do you think would be best/easiest/most economical i.e. best "bang for buck"? (hopefully no bangs though... )? I guess hub motors are simplest?

Stuart.

 

[coops]

Thanks flecc I suppose at least you still have a potential front hub motor if you replace the Torq's & lack those skills... maybe not ideal but useful nonetheless?

 

[flecc]

Just been doing a bit of surfing, and it seems that there are indeed a number of bespoke frame builders that will build it whatever way you want for reasonable prices too.

John

Yes, I knew of those sort of makers John, but the standards are too high, mainly for sporting types. You said reasonable prices, but starting at about £600, but which would be higher at probably £800 upwards for a battery frame variant they weren't experienced with, would make the finished bike very expensive indeed. Think motor/control side at £300, battery at least £250, decent wheels/tubes/tyres and wheel building at £180, derailleur parts, chainwheel and chain, crankset at the very least £90, then brakes and all the little bits, probably £100 or more, that's £1720 at least, and for mainly low priced components, so it could go well over £2000 for a higher standard.

I had in mind someone knocking out a batch to sell from stock at around £300 which would keep the price down.
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[flecc]

Thanks flecc I suppose at least you still have a potential front hub motor if you replace the Torq's & lack those skills... maybe not ideal but useful nonetheless?

Yes indeed, it's a great motor for 20" to 24" wheels, and has some use in 26" for speed but not to good hill climbing, but the 28" wheel of the torq went too far for anything other than fairly flat country, or elsewhere in a lightened and boosted version for use by a fairly light rider, like my T bike.
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[coops]

Thanks flecc.

I had in mind someone knocking out a batch to sell from stock at around £300 which would keep the price down.

Maybe, if there was sufficient demand, we could get hold of a batch of the sort of frames (if they're of good quality) that are used to make many of the lookalike electric bikes we see for sale all over Europe, and maybe even more widely?

Still rather radical though . Hey, that has a kind of ring to it for a name?

pedelecs radical?!

EDIT: On second thoughts, maybe not the wisest choice of terminology...

Stuart.

 

[flecc]

Maybe, if there was sufficient demand, we could get hold of a batch of the sort of frames (if they're of good quality) that are used to make many of the lookalike electric bikes we see for sale all over Europe, and maybe even more widely?

Stuart.

The Chinese wouldn't entertain any order for less than £10,000 probably, so not really an option, though it seems an attractive idea. The only way it might work is if a supplier of existing bikes got in a batch of frames as spares for the bikes he handled, but he'd have to be nuts to do that, conceivably doing himself out of sales.

There'd still be the forks problem as well, no choice of width and sprung/rigid.

Second hand e-bikes will become an increasingly attractive source of suitable frames as their electrics fail and they are left useless, so we have that to look forward to.

Maybe a Grandad cartoon of vulture like e-bike types following others around waiting for them to fail?
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[coops]

Second hand e-bikes will become an increasingly attractive source of suitable frames as their electrics fail and they are left useless, so we have that to look forward to.

Maybe a Grandad cartoon of vulture like e-bike types following others around waiting for them to fail?

Well, waste not, want not . The pedelecs "recycle" then?

 

[flecc]

The pedelecs "recycle" then?

Yes, or the Recyclagain, or the Againicle, or "I thought I'd thrown that away!"
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[coops]

Or, if you salvage it from the tip, "freewheels"! (working parts, batteries etc. not included )

 

[coops]

Just been reviewing the battery discussion earlier... (can't think on two things at once ). To whet your appetite a bit more John, see what you think...

Just thinking hypothetically at the mo. Each of those D cells weighs 166gms, so 20 would be 3.3Kg, 30 is 4.9Kg, 40 would be 6.6Kg, and 60 is a wopping 9.8Kg!!! (for ref, I carry the charger everywhere with me on my Twist, and I dont want to do that).

If I had a 36V motor like the puma (if theres a 250W version or one that can be adapted to 250W), then I would need at least 30 cells in series (or 60 in parrallel) and I would get power and range (esp from the 60).

So NiMH gives: (battery weights only)

20 x 11Ah (1 x 24V) is ~ 264Wh ~ 3.3kg+
40 x 11Ah (2 x 24V) is ~ 528Wh ~ 6.6kg+

30 x 11Ah (1 x 36V) is ~ 396Wh ~ 5kg
60 x 11Ah (2 x 36V) is ~ 792Wh !!! (but weighs ~ 10kg as you say!!!)

Current eZee batteries: 36V 9Ah ~324Wh NimH; 37V 10Ah ~370Wh Li

Since newer Li batteries are about 2/3 weight of NiMH for same capacity, roughly 3/2 (i.e. 1.5) times the capacity gives the same weight.

So how about "expanding" a battery case (like the T-bike case) as far as is practical to take as many Li batteries as possible, hopefully giving around 1.5 times the current NiMH capacity for the same weight i.e. around 500Wh for ~4.5 - 5kg.

That should give around 1.5 times the current range, and be less reduced by hills due to good motor gearing, so conservative possible ranges, even in mixed terrain, could be ~20-22.5 miles at 20mph (if delimited for off-road) ~ 25-30 miles at 17-18mph and around 40-45 miles at 15mph (3 hours trip), close to 50 miles at 11-13mph if you want a really long, slow "potter" for 4 hours .

Might be worth carrying the charger though, if they can be recharged in ~15-30 mins . This would cost a bit, mind, and I think I'd keep using my NiMH till I'm confident that these new Lithiums pass muster but its a possibility - I'm seriously considering a severe stress test, as I've said before, of a small capacity, portable lithium, say only a few Ah & 36V, to assess their performance. Hopefully by then we'll have a better idea of their rate of degradation over time, so it'll be more a question of performance.

Tempted? enough range for you? Are all the ideas converging?

One more thing - the tyres could be swapped for M+ similar to the T-bike's 2nd biggest performance enhancement, for better efficiency, which would just leave the biggest performance improver...

...think how well it'll perform for an optimum weight rider .

I think that's a contender, what do you think?

Stuart.

 

[prState]

Wouldn't the ideal E-bike frame be made (aside from low center of gravity, with a space to run different configurations of batteries), strong in necessary areas, like the motor to wheels, but still light in other areas? Or maybe that's a minimal change from what's already available?