UKC

I have a 3-4 year old Specialist bike and thinking of upgrading it to an eBike. Anyone got any views/experience?

converting?

dont.

if you want an E,  go buy an E.

 

Bafang mid motor.

It’ll take a couple of hours of your time but you’ll end up with a very capable e bike.

Hardest bit will possibly be trying to find somewhere to mount the battery.

I also used a Bafang Mid drive and it's worked fantastically.

The kit cost me £400 and the battery roughly the same although I suspect they are more expensive now.

At least with the Bafang you stand a chance of being able to fix it yourself without manufacturer's software. 

A conversion will always be a poor compromise. Sell your old bike and buy a bike that has been designed to be an e-bike.

Surely you mean downgrading it to an eBike?

I converted my 80’s Muddy Fox with a Dillenger kit about 2 years ago. Installation was easy and I’m very happy with it. One advantage to a conversion is that button only operation is an option as the regulations only apply to manufactured ebikes. The kit  currently costs £599.

Have done this to a Trek. The thing I would say you need to be careful is the battery mounting. The Bafang kit is pretty damned easy to fit, BUT the battery is heavy with a capital H. In my view, the standard bottle cage mounts on an Aluminium frame are just not man enough and if you actually use it with the battery mounted to the cage mounts off road, you stand a fairly decent chance of bending or breaking your frame. On the road, sure, no problem. Off road I'm dubious. hat said I was impressed with how well the motor kicked in and how powerful it was. The one I fitted was the most powerful, and I was able to do 30kmh down the road  with it derestricted. Obviously after that experiment I turned the restrictor back on.

check out TongSheng for alternative mid-drive kit. it has torque-based pedal assist rather that cadence-based..

https://www.cyclingnews.com/features/best-electric-bike-conversion-kits-giv...

I'd that right?

So I could mount a kit o n my bike and bazz around at 20mph?

Shirley Knott?

Not. You can buy off road ebikes that aren't road legal, or make one as Mark suggests. But if you do get collared it will be a fine and points on your licence if you have one. 

Got a job with deliveroo?

Legally, only on private land.

20MPH sounds about right, to keep it legal (then there is the 250W limit) and I checked the regulations (some months ago) concerning the button only limitation. Something I noticed with my kit was that out of the box the 20MPH limit didn’t seem to rigorously enforced, as I usually get about 24MPH on the flat (but that could be speedo inaccuracy), before you even consider hacking the controller or telling it you are using much smaller wheels. OK, from a purely cycling perspective, it’s cheating. But when you are 62 with a heart condition and am ‘cycling’ uphill home from the supermarket, with a backpack full of shopping, on a hot summers day, the option to just press the button and watch the scenery go by is a great way to get home.

Oop’s, it seems 15.5MPH is the legal limit.

Or not, if it goes to a jury and they somehow manage to acquit: https://www.bbc.co.uk/news/uk-england-london-51707616 - as well as the main charge, he was also found not guilty of various offences under the legislation surrounding the use of motor vehicles on public roads, despite riding a non-EAPC-compliant e-bike.

Not strictly correct.  The "Kit Motors" section here: https://www.pedelecs.co.uk/forum/threads/pedelec-law-the-details.37594/ states:

...both individuals and suppliers operate in a legal vacuum in which all* try to supply and/or use as closely conforming to the complete e-bike law as they can, trusting that is acceptable. That has always worked throughout all of Europe and the UK without any mention of a possible prosecution, providing the three main points of the law are adhered to, i.e. 250 watts maximum assist, 15.5 mph maximum assist speed and power only when pedalling.

It then goes on to explain how one might go about ensuring that one's home-brewed e-bike definitely is a road legal EAPC, by following the Single Vehicle Approval (SVA) process.  What's particularly relevant to the question of having a throttle is that it goes on to state:

However, if you get and accept SVA approval as well at the same time...you will be able to have a fully acting throttle on a post December 2015 pedelec with it still considered a bureaucracy free pedelec, a bonus.

There is further explanation of the above para in the "Getting legal permission to have a fully acting 'Twist and Go' throttle on a pedelec" and the related "Grandfather Rights" section further up in the same post.

TBH, though, so long as you don't take the piss e.g. blatant speeding, I suspect you're more likely to get done for riding without lights (or pedal reflectors, if the police officer feels like being really picky), than you are for having an illegal throttle, given that it is theoretically possible for an e-bike so fitted to be perfectly within the law.  (In much the same way, I suppose, that it is theoretically possible to park a car on the footway without actually committing the offence of driving it on the footway e.g. if you have access to a crane.)

* This strikes me as being a somewhat starry-eyed view of the home-brew e-bike market.

Swytch front wheel kit is good*, but expensive

They send you a replacement wheel of whatever size you need. Downside is that it only works on drop-outs, not thru-axle.

Fitting is pretty simple, and will fit most bikes (note - definitely doesn't fit a Trek XCalibur 7 2021 due to BB/pedal/chainstay combo). It requires either clearance between the BB and the non-drive crank, or clearance between the crank and the chainstay for the cadence sensor to fit.

Battery is small and portable, but still gives a 50km range on the lowest assist setting.
3rd party batteries and connectors can boost this more

*Had issues with the battery bracket failing (electrical, not mechanical) 3 times over 3 years. While in warranty, not a problem, but gets expensive afterwards. Will need to pull apart one of the failed ones to see what the issue is.

Hmm... Probably not selling this well...

My understanding is that the front wheel hub motors, while about the easiest conversion to actually do and fine on the flat, aren't actually that great on steep hills, as the weight distribution can limit the traction?

Have a look at this website - loads of info:

https://ebiketips.road.cc/content/advice/features/how-easy-is-it-to-convert...

This is all really helpful, thanks folks. Lots of homework!

I'd agree with that: if the OP is intending to use their converted MTB on proper MTB-type trails then I think a front wheel drive conversion is probably the last thing they should consider.  As well as the traction being compromised on steep inclines, trying to put propelling torque through the front wheel is likely to reduce the effectiveness of the steering as the weight moves towards the back - not ideal on a technical climb.

Hi, I hadn't considered that ambiguity in my OP. For the record, the bike (actually my wife's, not mine) has never - and is unlikely to ever - be on anything more challenging than a mild bridleway.  

For the most superficial of reasons I'd not convert one, every single ebike conversion looks bloody ugly.

I don't mind ugly with a purpose like a cargo bike, but the cabling is always a snake's wedding and batteries look perched and unbalanced.

I understand it's an easy route to a powerful ebike but it's just too much for me! Something designed to hold the battery in the downtube and route all the cables internally looks better.

Make sure you also consider an e-gravel bike.

One of my friend has one of these and totally rates it for road and easy gravel/BW:

https://www.ribblecycles.co.uk/ribble-gravel-al-e-apex-1x/?utm_source=googl...

On the road (and compacted trail) I've done 20% inclines without any traction issues (even with the power ramped up to the max)

On loose gravel, yeah... wheel spins at a certain point.