Upgrading from a Swytch converted Brompton

[jazzyr85]

Hello, I'm looking for something a bit more rugged and comfortable to ride than my Swytch-fitted Brompton.

I'm looking for something with fat tyres, small enough to fit into a small elevator (175cm diagonal) and/or foldable, and with an upright seating position. The battery should last for at least 25 miles and should be UK legal(ish).

Budget is no more than £1.5K

A few that have interested me are:

- Fiido M1/M21 - I really like the M21 with the torque sensor and it's got a 500w motor restricted to 250w. The only thing is the handlebars are quite low down.

- Radbike RadExpand 5 - The seating position looks better on this one but apparently it's a significant downgrade from their previous model.

I think if I could increase the handlebar height on the M21 it would be perfect. Has anyone had any luck with this on the M21 or M1 (Pro)?

 

[Bonzo Banana]

Two things that would be important to me is the legality of the ebike in question and how proprietary the parts are. Is it using standard components that can easily be replaced or serviced. I look at ebikes like the M21 and I think will I be able to get a replacement controller in a few years and will that proprietary rear suspension be replaceable for reasonable money. If you are going for a fat tyre ebike which in itself offers additional comfort why then add in more suspension on top which adds extra weight and complexity. Unless you have buttocks made of porcelain surely you can go over the top with regard suspension. Tyres can be inflated to the correct pressure so that they provide a suspension effect for your weight.

I've never ridden a Brompton myself but have heard its quite a comfortable bike, the steel frame flexes, it has a rear rubber block that acts as rear suspension, the extended saddle post will flex. A sprung saddle could add additional comfort to one.

 

[jazzyr85]

I'm really looking for something built as an electric from the ground up. The Brompton isn't it, even the electric Brompton seems like an afterthought.

I just need a bike I can either get upstairs easily enough or fit inside a smallish lift. I don't need to take it on a train or anything. Though it would be nice if it could fit inside my car boot.

 

[StuartsProjects]

I'm looking for something with fat tyres, small enough to fit into a small elevator (175cm diagonal) and/or foldable, and with an upright seating position. The battery should last for at least 25 miles and should be UK legal(ish).

My full size eBike conversion on a mountain bike would fit in a '175cm diagonal' lift although I would not want to be in there with it.

I also have an eBike Brompton, which is a lot smaller.

Whilst you might understand what a 'smallish lift' means or implies, I doubt anyone else does.

 

[jazzyr85]

My full size eBike conversion on a mountain bike would fit in a '175cm diagonal' lift although I would not want to be in there with it.

I also have an eBike Brompton, which is a lot smaller.

Whilst you might understand what a 'smallish lift' means or implies, I doubt anyone else does.

Yes, that's why I put the exact size in my original post.

What size is your mountain bike?

 

[StuartsProjects]

What size is your mountain bike?

172cm.

 

[cyclebuddy]

I think if I could increase the handlebar height on the M21 it would be perfect. Has anyone had any luck with this on the M21 or M1 (Pro)?

Adding riser bars is a common upgrade on those bikes. IIRC, it needs a 25.4mm diameter bar at the stem to fit the existing clamp. Most seem to use BMX riser bars to give it a cruiser look; there's plenty of choice in terms of rise height and bar width that'd work.

 

[jazzyr85]

I decided not to bother with the Fiido, I'm now looking for a full size bike that's light enough for me to tip up onto the back wheel so it fits in the lift.

Would a 50nm torque Bosch Mid-Drive be a noticeable enough improvement over the Swytch kit's 42nm front hub?

 

[matthewslack]

I decided not to bother with the Fiido, I'm now looking for a full size bike that's light enough for me to tip up onto the back wheel so it fits in the lift.

Would a 50nm torque Bosch Mid-Drivebe a noticeable enough improvement over the Swytch kit's 42nm front hub?

They are very different things. You already know Swytch from your Brompton, so a test ride on that mid-drive Bosch is probably what you need to help the decision.

I only have experience riding Shimano 40Nm mid-drive, and I cannot imagine that the Swytch would be anywhere near as capable or adaptable.

It comes down to the riding you want/need to do. The Swytch might handle my commuting, although I have doubts about the last hill on the way home - so it might do the needs, but the long distance adventures? Not a chance.

 

[cyclebuddy]

As Matthew says, there's a world of difference between a torque sensor mid-drive and a cadence sensor hub drive.

I have a Fiido D11 20" folder with 35Nm rear hub and cadence sensor, an Ebco hybrid 700c wheel TranzX 60Nm mid-drive with RPM sensor, and a Greenway hybrid 700c Bafang 80Nm mid-drive with torque sensor.

On paper it's the latter that has the most clout. I bought the Fiido specifically for a commute and deliberately chose the D11 with cadence sensor. It doesn't ride as if it has less power, and requires less effort than a torque sensor bike (which IMHO is what you want for a commute). All three bikes ride very differently and I really do enjoy riding them all. But perhaps oddly, because the Fiido is small and "chuck-able", I find I tend to ride it the most for practical purposes, and the other two for weekend leisure rides.

You really do need to test ride a few different systems to find what works best for you.

 

[Bonzo Banana]

I decided not to bother with the Fiido, I'm now looking for a full size bike that's light enough for me to tip up onto the back wheel so it fits in the lift.

Would a 50nm torque Bosch Mid-Drive be a noticeable enough improvement over the Swytch kit's 42nm front hub?

I didn't realise Swytch kit's were so high powered in torque. I guess I assumed that because they provide such weedy batteries they would have reduced torque. Maybe the motor is capable of that torque but the battery would struggle.

Anyway with mid-drive you have to calculate the real torque to compare to hub motors as the basic figures are not comparable. A mid-drive normally has the torque figure given at the crank which lets say is 50Nm but because its delivering its power through the chain you will lose some power maybe around 2-3Nm. Then you have to calculate the gear ratio. If you have a 42T at the front and your maximum cog at the rear is also 42T then you can state you have torque of around 47Nm peak however if you have a 42T at the front and a 34T at the back you have torque of 34 shared by 42T x the 47Nm so about 38Nm torque in the lowest gear.

Contrast that with a e-mountain bike with a 95Nm power at the crank and perhaps a 38T at the front and a 50T at the back and you have 50 shared by 38 and then times 92Nm which is 121Nm torque. A huge figure. Also the riders own power will be scaled by that same gear as well so probably achieving an easy 50Nm or more albeit at admittedly lowish speeds.

A lot of what people want comes down to perspective. I must admit I don't see much point in mid-drive when it has low torque output but another person might say they get the scaled power and nice feel without the excessive wear on the drivetrain and prolonged motor life compared to high torque mid-drive motors. So its a win. I'm very tight fisted and resent spending a penny I don't have to so go down the value route pretty much all the time unless I need the superior performance of mid-drive for a proper e-mountain bike.

 

[jazzyr85]

The Swytch Is surprisingly nippy but the battery is terrible and the Brompton doesn't feel the most stable at higher speeds, not to mention the potholes on the road and towpaths. I wanted a full size bike because I thought it might be more enjoyable riding in the evenings and weekends.

 

[StuartsProjects]

The Swytch Is surprisingly nippy but the battery is terrible and the Brompton doesn't feel the most stable at higher speeds, not to mention the potholes on the road and towpaths. I wanted a full size bike because I thought it might be more enjoyable riding in the evenings and weekends.

I have a Swytch converted Brompton and a DIY Titanium hardtail Mountain Bike conversion.

The Brompton is OK for short distances and for shopping. Whilst you can normally avoid potholes etc, it can be hard going on some of the roads round by me where maintenace seems to have been abandoned.

The mountain bike has a rear hub motor and is fitted with Schwalbe Plus Tour 1.75" tyres and is very much more comfortable to ride on roads and cycle paths, I was out for 2 hours yesterday, no problems. The mountain bike is not much affected by the holes and crevasses in the roads.

There are some long steep hills round here, quiet of traffic fortunately, and whilst the Mountain Bike is stable and secure at 45mph+, I would be scared going that fast on the Brompton.

As for the comment on the Battery, I find mine OK, but have been wondering what I would do if it needed replacing. Controllers, displays, brake and pedal sensors as seperate items are low cost and it might be possible to do a DIY conversion across to a 'standard' battery. There may be room on the Top Tube to take a bottle battery or small shark style.

 

[matthewslack]

The Swytch Is surprisingly nippy but the battery is terrible and the Brompton doesn't feel the most stable at higher speeds, not to mention the potholes on the road and towpaths. I wanted a full size bike because I thought it might be more enjoyable riding in the evenings and weekends.

Your horizons will be broader with the Bosch, I'd go so far as to say almost no limits. Certainly extends what you can do outside of commuting use. If you can get a test ride of meaningful length in representative terrain, you'll see what the possibilities are.

 

[jazzyr85]

I was thinking of getting a Gazelle Grenoble C7+, which has a Bosch Active Line Plus middrive. It weighs 24.4kg. Obviously I'm not going to be carrying it upstairs but do you reckon it would be manageable enough to tip up onto its rear wheel, so it fits in the lift?

 

[matthewslack]

I was thinking of getting a Gazelle Grenoble C7+, which has a Bosch Active Line Plus middrive. It weighs 24.4kg. Obviously I'm not going to be carrying it upstairs but do you reckon it would be manageable enough to tip up onto its rear wheel, so it fits in the lift?

I can tip my Ridgeback X2 easily enough, using the rear brake to help, don't have a lift to try the second part! It is similar in weight, 26kg I think.