Converting a mountain bike into an e-bike, worth it?

[JohnE]

I have just done a conversion on my old Marin Rocksprings MTB which was being rarely used. I fitted a TSDZ2 48v motor from Whoosh with a 48v 17ah battery. It was a bit of a challenge to fit on a full suspension MTB - I had to fit the battery on the bottom of the downtube, and had to improvise the fitting of the bridge plate. Mine is pedal assist only, no throttle, so I still get a work out. I have done 3 short rides so far amounting to 47 miles and nearly 2000 feet of climbing, and still have 5 of the 6 bars on the battery still remaining, so am expecting to get over 100 miles from a full charge. This may be optimistic as I'm still experimenting with the power assist level.

It's great fun. I now use it more than my road bike ! It's a lot heavier than the road bike (I think the disk brakes are essential) but it's faster !!

 

[confusedcyclist]

@JohnE Well, it's certainly something to behold. Nice job getting it all to work on such an awkward frame! Are those velcrostraps? Other than gravity, what's stopping the battery orienting around the down tube and whacking you in the knee/shins? Also, no fouling of the battery on the front wheel/guards during rough stuff?

 

[JohnE]

Yes they are velcro straps. However there are 4 rivnuts holding the battery mounting plate securely in place. Feels rock solid to me. The velcro straps are just overkill really as I wasn't sure how much weight the rivnuts would take. The battery is a bit of a beast. Didn't want it dropping off as I went over the first pothole.
No fouling on the front wheel ... yet. I've bounced on the forks several times and haven't managed any fouling. But, I'm an old git pensioner and don't do real rough stuff any more ... my off road these days is generally down converted railway tracks on relatively smooth surfaces. Also the front forks are adjusted so there's minimal travel. The mudguard is plastic with a bit of give in it. Hopefully fouling won't be an issue.

 

[confusedcyclist]

Sounds like you've thought this through

 

[Phil Fouracre]

And by using a kit you get round that crappy 15mph max limit on the assistance. Mine is set at 20. Oh and the kit has a trigger that you can't get on UK stock e-bikes.

Agree about the trigger kits! Are you sure about the ‘crappy limit’? However you do it, if you exceed the 15.5 mph assist ‘tis illegal🙈

 

[Wyn Davies]

Thank you, I'll probably go for 9ah or somewhere around there then just to give me a bit more flexibility if there's particularly strong headwinds which do happen around where I live. I'm only 52kg (weighed today) so I'm guessing I'd be alright, pretty strong cyclist as it is.

My ebike has three modes Eco sport and Power it's claimed 205kl in Eco how do you culcalate what sport mode will do

 

[CXRAndy]

My ebike has three modes Eco sport and Power it's claimed 205kl in Eco how do you culcalate what sport mode will do

Best way, start fully charged, ride it hard in sports mode till it stops.

 

[Wyn Davies]

Best way, start fully charged, ride it hard in sports mode till it stops.

Brilliant why didn't I think of that .

 

[samsbike]

this is interesting, as I want my mtb to be able to be used as a mtb and contacted Whoosh.

My understanding of their response was that it would not be worth the conversion (to use as a proper mtb) as the rear hub motor, would impact handling, and the mid mount may impact clearance.

Also would need a much better battery solution as the frame is not designed to have that weight thrown around.

 

[CXRAndy]

this is interesting, as I want my mtb to be able to be used as a mtb and contacted Whoosh.

My understanding of their response was that it would not be worth the conversion (to use as a proper mtb) as the rear hub motor, would impact handling, and the mid mount may impact clearance.

Also would need a much better battery solution as the frame is not designed to have that weight thrown around.

If I was going to convert a MTB to an Ebike. I would use a steel frame bike, weld brackets to hold battery more securely.

I would use a Bafang BBSHD 1000W motor.

I do have a hard tail Kona Honzo donor, one day I'll convert.