Yet Another Cycling Forum

General Category => The Knowledge => Topic started by: nobby on 10 April, 2021, 01:42:29 pm

Title: Electrickery wheels - help please.
Post by: nobby on 10 April, 2021, 01:42:29 pm
If my Bacchetta Giro 20 isn't sold shortly I am going to give it an electric motor. I didn't like it with the mid drive motor stuck on the front so I will use an in wheel motor.

A front wheel motor (20" wheel) would mean no alterations to gears but for uphill assistance would a motor in the rear wheel (26") be best?
Any advice gratefully received.
Cheers.
Title: Re: Electrickery wheels - help please.
Post by: Kim on 10 April, 2021, 01:45:48 pm
A smaller wheel means you get more torque from the motor.  I don't have any experience of riding a FWD recumbent up steep hills, though.
Title: Re: Electrickery wheels - help please.
Post by: LittleWheelsandBig on 10 April, 2021, 01:47:52 pm
Electric hub motors are tuned to their wheel size. A hub intended for a 20” wheel has a different performance profile to the same make of hub intended for a 26” wheel.
Title: Re: Electrickery wheels - help please.
Post by: nobby on 10 April, 2021, 02:01:35 pm
Electric hub motors are tuned to their wheel size. A hub intended for a 20” wheel has a different performance profile to the same make of hub intended for a 26” wheel.
That makes sense so I'd have to make comparisons.
No rule of thumb to which is better?
Title: Re: Electrickery wheels - help please.
Post by: nobby on 10 April, 2021, 02:03:04 pm
A smaller wheel means you get more torque from the motor.  I don't have any experience of riding a FWD recumbent up steep hills, though.
From my one lunger motorcycle days torque was good, I seem to recall.
Title: Re: Electrickery wheels - help please.
Post by: LittleWheelsandBig on 10 April, 2021, 02:19:10 pm
I don’t have enough knowledge of the current state of the art to give any worthwhile advice.
Title: Re: Electrickery wheels - help please.
Post by: Diver300 on 10 April, 2021, 02:35:03 pm
At any reasonable speed, and unless there is a very odd weight distribution or very low grip, the maximum power allowed won’t spin either wheel, so either would be equally good.
Title: Re: Electrickery wheels - help please.
Post by: CAMRAMan on 10 April, 2021, 02:35:29 pm
I've a feeling that most of the weight of a recumbent is on the rear wheel, so you might experience traction issues on steeper gradients. I had similar issues on an upwrong with Dutch style bars.

You might be better off posting your question on pedelecs.co.uk/forum to get more experienced eyes to give you answers.

FWIW, I've had front-, rear- and mid-drive set ups. FWD was the least satisfactory of all three in terms of both performance and looks. The wiring can't be avoided, but is much harder to disguise on a FWD set up.
Title: Re: Electrickery wheels - help please.
Post by: Kim on 10 April, 2021, 02:53:28 pm
I've a feeling that most of the weight of a recumbent is on the rear wheel

*snork*

It's very much the opposite, though by how much depends on the geometry and how much luggage you're carrying.  As a general rule, (particularly for very front-heavy things like tadpole trikes and SWB bikes on start-off where the rider has to sit forward to get a foot down) a bit more weight over the rear wheel is a good thing.
Title: Re: Electrickery wheels - help please.
Post by: nobby on 10 April, 2021, 03:24:30 pm
I don’t have enough knowledge of the current state of the art to give any worthwhile advice.
Thanks for your help.
Title: Re: Electrickery wheels - help please.
Post by: nobby on 10 April, 2021, 03:40:59 pm

You might be better off posting your question on pedelecs.co.uk/forum to get more experienced eyes to give you answers.
thanks for that link. I went there and discovered I am a member! I blame age.


FWIW, I've had front-, rear- and mid-drive set ups. FWD was the least satisfactory of all three in terms of both performance and looks. The wiring can't be avoided, but is much harder to disguise on a FWD set up.
Useful to know. ta.
Title: Re: Electrickery wheels - help please.
Post by: nobby on 10 April, 2021, 03:42:11 pm
At any reasonable speed, and unless there is a very odd weight distribution or very low grip, the maximum power allowed won’t spin either wheel, so either would be equally good.
Thank you. I am expecting to be the only odd bit of weight.
Title: Re: Electrickery wheels - help please.
Post by: ppg on 10 April, 2021, 03:48:15 pm
I only have upright bikes so cannot tailor response to your specific needs, but for climbing hills RWD is definitely preferable.

On anything steeper than 15% both my 2 road bikes with FWD will lose traction, particularly on gravelly surfaces. Standing on the pedals and pushing down on the bars helps (obv not in your case!) but then invariably the rear starts spinning!

My MTB has RWD and is far better at climbing. The slight drawback is the faff of getting the wheel in and out with the derailleur and chain.

Ditto pedelecs.co.uk for better info
Title: Re: Electrickery wheels - help please.
Post by: nobby on 10 April, 2021, 05:34:12 pm

My MTB has RWD and is far better at climbing. The slight drawback is the faff of getting the wheel in and out with the derailleur and chain.

Ditto pedelecs.co.uk for better info
Thanks for that.
Title: Re: Electrickery wheels - help please.
Post by: fd3 on 10 April, 2021, 06:55:23 pm
Have you advertised your bike on bhpc and ctc forum?
Title: Re: Electrickery wheels - help please.
Post by: nobby on 10 April, 2021, 07:49:25 pm
Have you advertised your bike on bhpc and ctc forum?

No, not yet. I may but I am having second thoughts because someone has pointed out that the newish Bacchetta E bike is a Giro 20 with a Shimano Steps motor hung on the front.
I am starting to think there may be a flaw in my thinking!