XC rider looking to electrify a DH mountain bike

[Liquidbarrel]

Hi guys, I have been riding an XC mountain bike for 12 months but have recently purchased an old downhill bike which I think/hope is suitable for conversion to an ebike.
I am not really sure what I am doing but plan to have fun researching, building then riding the outcome.
Would appreciate any advice on motor and battery selection for my DH ride. I bought a 2002 banshee scream freeride because it’s built tough, has large triangle for battery and has good brakes & suspension. I am not so mechanically inclined so not really sure where to start. I am not looking for speed but need power to get my 100kg plus bike up some steep inclines. Also would be good to get 50km ride distance out of battery. My initial research points toward a mid drive bbshd Bafang. But is there anything else out there (maybe cheaper) ? Or is a hub drive an option. Note: I am based in Australia but can import most gear pretty easily.
Any suggestions appreciated.

 

[R120]

not that many self builders on the forum. @Mabman is (I think!) our most experienced self building member, so he may be able to help

 

[Gary]

Being brutally honest. You're wasting your time and would be throwing money at a dud.
The Banshee had pretty terrible DH geometry and mediocre suspension characteristics even back in 2002, more like something from 1998-2000 than 2002. DH bike design and geometry has come an awful long way since then. infact any off the shelf enduro bike these days will outperform your scream in every way. Adding a heavy motor and battery to it's already considerably heavy weight is also only going to make it even worse handling. Especially if you plan on fitting a big enough battery for 50km of DH based riding (20km and ~4000ft elevation is about all you'd get out of a 504wh battery from all the popular mid motors on dedicated Emtbs ). Not to mention a 17yr old Aluminium DH bike being well past it's durability window.There's no way I'd want to ride one fast down anything gnarly or off any big jumps nevermind with 15lb of battery and motor bolted to the frame.
IMO Hub drive would be pretty horrible regarding handling on a DH bike too.

You'd get far better performance just buying almost any longer travel Emtb off the shelf. a Specialized Kenevo, Vitus ESommet or Commencal Meta power are all far better performing descenders than the Banshee.

Interesting as a project I suppose if you have money to throw at a turd or happened to already have the motor/kit at your disposal but that's about it.

Sorry.

 

[Janluke]

Many years ago a I converted a Marin full suss with a cheap kit(I'm a below knee amputee and struggle on big climbs). It did work but it's a world away from the capabilities of a modern ebike

 

[MattyB]

Being brutally honest. You're wasting your time and would be throwing money at a dud.
The Banshee had pretty terrible DH geometry and mediocre suspension characteristics even back in 2002, more like something from 1998-2000 than 2002. DH bike design and geometry has come an awful long way since then. infact any off the shelf enduro bike these days will outperform your scream in every way. Adding a heavy motor and battery to it's already considerably heavy weight is also only going to make it even worse handling. Especially if you plan on fitting a big enough battery for 50km of DH based riding (20km and ~4000ft elevation is about all you'd get out of a 504wh battery from all the popular mid motors on dedicated Emtbs ). Not to mention a 17yr old Aluminium DH bike being well past it's durability window.There's no way I'd want to ride one fast down anything gnarly or off any big jumps nevermind with 15lb of battery and motor bolted to the frame.
IMO Hub drive would be pretty horrible regarding handling on a DH bike too.

You'd get far better performance just buying almost any longer travel Emtb off the shelf. a Specialized Kenevo, Vitus ESommet or Commencal Meta power are all far better performing descenders than the Banshee.

Interesting as a project I suppose if you have money to throw at a turd or happened to already have the motor/kit at your disposal but that's about it.

Sorry.

We may need a "Mic drop" emoji for posts like that... I do agree though - strapping on a heavy aftermarket kit to a frame and suspension components that old would seem to be asking for (potentially very painful) trouble.

 

[Standingwaves]

I agree with the posts here. Huge pain, poor performace and $$$$ by the time you are done. Check out the endlesssphere site for DIY info.

 

[Kernow]

I looked at converting my wife’s hardtail cube , but I was well over a £1000 before I even started , selling the cube and buying vitus hardtail ebike made more sense in that case , especially if you factor in the resale or residual value of a decent mtb compared to a conversion .
I was lucky in the end all she wanted was new running shoes , don’t like bikes ?

 

[Julio]

A local bike shop soes eBike conversions for NZ$1650 (about £850). He uses Bafang motors. Battery is usually mounted on a rear carrier, but can be frame mounted. I had considered doing this conversion on my hardtail 29er commuter, but instead bought a Trek Powerfly LT (whole lotta fun!). I might still do the Bafang conversion on my commuter one day when funds allow, but the extra weight on a hardtail commuter is a lot different from on a DH or Park bike.

(I have no opinion on the Banshee ?).

 

[Mabman]

Thanks for the shout @R120 but I don't think I can be of much help here. Converting heavy old DH bikes with heavy motors like the BBSHD and the heavy battery that it would take to haul everything around for 50k is out of my scope of experience.

I would suggest the Endless Sphere forum for you Liquid Barrel as that type of build has been going on there for years and plenty of info on how to get it done.

 

[Liquidbarrel]

Thanks for all the responses guys...good to get feedback. I certainly appreciate that I could spend 5k-10k on a purpose built and it would ‘probably’ be a better outcome. But I got the banshee cheap and the thing is built like a tank. Yes it does not have capabilities of modern downhill bikes but I don’t have capabilities of modern downhill riders either. I don’t really care too much for downhill performance but the bike should have sufficient braking, suspension and frame strength to support a motor.
I will ponder my ‘experiment’ options and in the meantime wait for the price of purpose built ebike to come down...
PS. Have been on endless sphere forum and the mindset is certainly different to this forum with regards to diy versus off the rack

 

[R120]

You can spend 2k on a new purpose built EMTB and have a better outcome, but I get the appeal of building one yourself.

Bare in mind that this forum is pretty much dedicated to Class 1 Pedelec bikes, i.e those that you have to peddle, have no throttle, and are limited to 250w/Speed limit in your area, and whilst I and many others are not anti the more extreme electric bikes out there, they are not really the kind of bikes that many of us would ride, as most of us are looking for a bike that is as close as possible to a regular MTB with a helping hand from the motor, and the self build options just don't do that.

No converted bike will ever come close to a properly designed purpose built one, even a basic one, when it comes to Mountain Bikes, simply because of key elements.

Namely that the purpose built bikes are designed to accommodate the battery and motor in a way that doesn't compromise the handling, or get in the way of riding the bike - you don't want weight high up on an MTB, and you don't want a motor sticking out in front of your BB right in the firing line of trail debris and logs etc. Purpose built bikes have geometry that takes into account the addition of a motor, and help mitigate it, but also maximise the benefits of it. Finally they are usually specified with components such as brakes etc that are designed to handle the extra weight and power.

With a normal bike, or one for just cruising on fire roads and tracks, I can see conversion as an option, but for proper trail riding I would not consider the option. I am not saying you cant build a perfectly rideable home build bike, but you won't build one that can perform aas well as a purpose built one.

 

[Gary]

Thanks for all the responses guys...good to get feedback. I certainly appreciate that I could spend 5k-10k on a purpose built and it would ‘probably’ be a better outcome.

Er... sorry. there's no probably about it. I've ridden a few banshee screams.

But I got the banshee cheap and the thing is built like a tank.

Sorry, but tanks aren't built from 7005 series aluminium for a very good reason.
A mate had one and snapped his frame right infront of me at my local DH spot a few years back. He's not exactly a gnarly rider either.

Yes it does not have capabilities of modern downhill bikes but I don’t have capabilities of modern downhill riders either. I don’t really care too much for downhill performance but the bike should have sufficient braking, suspension and frame strength to support a motor.

It's a second hand 17 year old Aluminium DH frame. Even if you knew it's full history there's no way it's still a suitable candidate for adding a motor to. If you're determined to go down this route I'd advise you least use something newer. S/H 5 yr old one previous owner 26" wheel DH bikes sell for pennies and it's far more likely you'll be able to get a true idea of the sort of use it's had

PS. Have been on endless sphere forum and the mindset is certainly different to this forum with regards to diy versus off the rack

With respect not one of those guys even mentioned the age of your frame, it's fatigue life, the terrible frame geometry and not one of them seems to have any experience with either your frame or fork.
There's only one reason anyone ever fitted a Marzocchi Super Monster fork to any frame
FYI It's because they wanted to emulate this guy

 

[Liquidbarrel]

Glad to have the devils advocate here...genuinely appreciate everyone’s input. Incidentally, I just hired a Specialized Kenevo Comp and rode some trails in New South Wales (Tathra). Really nice bike except for two things -cost $7200 AUD and fact that motor cuts out at 25km per hour (legal limit). Felt heavy to walk it up and down steep hills but felt balanced to ride. The main advantage was that I could easily pedal up hills and enjoy more downhill and sightseeing.

 

[Kernow]

Glad to have the devils advocate here...genuinely appreciate everyone’s input. Incidentally, I just hired a Specialized Kenevo Comp and rode some trails in New South Wales (Tathra). Really nice bike except for two things -cost $7200 AUD and fact that motor cuts out at 25km per hour (legal limit). Felt heavy to walk it up and down steep hills but felt balanced to ride. The main advantage was that I could easily pedal up hills and enjoy more downhill and sightseeing.

Both those problems cost and cut out are easily cured , there’s a section for derestricting on here , as for cost your looking at the most expensive brand check out vitus, canyon , commencal among others , other brands that are expensive here may not be there , such as Merida

 

[Krisj]

Being brutally honest. You're wasting your time and would be throwing money at a dud.
The Banshee had pretty terrible DH geometry and mediocre suspension characteristics even back in 2002, more like something from 1998-2000 than 2002. DH bike design and geometry has come an awful long way since then. infact any off the shelf enduro bike these days will outperform your scream in every way. Adding a heavy motor and battery to it's already considerably heavy weight is also only going to make it even worse handling. Especially if you plan on fitting a big enough battery for 50km of DH based riding (20km and ~4000ft elevation is about all you'd get out of a 504wh battery from all the popular mid motors on dedicated Emtbs ). Not to mention a 17yr old Aluminium DH bike being well past it's durability window.There's no way I'd want to ride one fast down anything gnarly or off any big jumps nevermind with 15lb of battery and motor bolted to the frame.
IMO Hub drive would be pretty horrible regarding handling on a DH bike too.

You'd get far better performance just buying almost any longer travel Emtb off the shelf. a Specialized Kenevo, Vitus ESommet or Commencal Meta power are all far better performing descenders than the Banshee.

Interesting as a project I suppose if you have money to throw at a turd or happened to already have the motor/kit at your disposal but that's about it.

Sorry.

Dude you are a legend ??????
My thoughts exactly on the project.

 

[Liquidbarrel]

Krisj instead of just back slapping someone who actually had opinions/reasons for his comments how about you provide some value yourself. From there I will try and determine you are anti ebike conversions or just don’t like old banshees...

 

[R120]

I dont think anyone is anti conversions, just making the point that if you are going to sink some money into something there may actually be off the shelf EMTB's that are viable for the riding you want to do, closer to the price you want to spend.

The main point I would make/question I would ask, is are you looking to put together a bike that is similar to a Class 1 Pedelec EMTB or are you looking to build a faster de restricted bike which also has throttle control? They are two very different things.

 

[Gary]

Yeah I'm in no way anti DIY ebike conversion or anti Banshee. Banshee have made some pretty decent bikes since their ropey old huck bike days.

Kernow and R120's advice above is good on the cost and assist limit issues you mentioned putting you off the Kenevo.

 

[Liquidbarrel]

I dont think anyone is anti conversions, just making the point that if you are going to sink some money into something there may actually be off the shelf EMTB's that are viable for the riding you want to do, closer to the price you want to spend.

The main point I would make/question I would ask, is are you looking to put together a bike that is similar to a Class 1 Pedelec EMTB or are you looking to build a faster de restricted bike which also has throttle control? They are two very different things.

I am not a downhill rider I just wanted to convert a bike that can sustain a motor, some bumps and has decent stopping power. Ideally I would like to ride more but living on top of a 10% gradient hill has discouraged me from riding. So Basically I just want a boost to get up hills so I can ride on roads and on some XC. Doesn’t need to be quicker than 25kph (which is the Aussie limit)....but ultimately I need enough power to get me (100kg) up a hill.

 

[Liquidbarrel]

I am not a downhill rider I just wanted to convert a bike that can sustain a motor, some bumps and has decent stopping power. Ideally I would like to ride more but living on top of a 10% gradient hill has discouraged me from riding. So Basically I just want a boost to get up hills so I can ride on roads and on some XC. Doesn’t need to be quicker than 25kph (which is the Aussie limit)....but ultimately I need enough power to get me (100kg) up a hill.

And just to clarify . I didn’t have problem with actual speed itself being 25kph. I just didn’t like the way it felt i.e. the dragging effect I noticed on the Lenovo. Maybe you get used to it but it almost felt like it was applying brakes...

 

[njn]

Years ago, I built a 2009 giant glory with a cyclone drive before proper bikes were available. That said, I would never use a kit again with today's ebikes easily available.

 

[Krisj]

@Liquidbarrel dude I have no problem with the old downhill bikes I used to race them back in the 90’s and back in the day they were the bomb , but hence(( back in the day )
Today as technology has moved on hugely
There is surely an off the shelf bike out there today which would be exactly what your looking for ,which would save you money and pain staking hours trying to convert an old down hill rig
Hope you find what your looking for and good luck if you choose to attempt your project. ??

 

[Gary]

And just to clarify . I didn’t have problem with actual speed itself being 25kph. I just didn’t like the way it felt i.e. the dragging effect I noticed on the Lenovo. Maybe you get used to it but it almost felt like it was applying brakes...

The Brose motors used in Kenevos completely de-couple when they stop assisting and as such have no drag. What you felt was the sudden difference between blissfully being assisted and no longer having any assist. All the drag you felt was down the weight of the bike and drag of the tyres. Try pedalling your Banshee on the flat or uphill above 25kph. it'll probably feel even worse.

 

[CreativeSource 9]

Hello Bubby
Yeah I agree with the chaps, You need to buy a reasonable donor bike. You usually get a bigger triangle for that big powerful battery if you choose a hardtail. I'll post a photo of the build I've just completed, and if it's of any interest to you then get back to Me with any questions. But as for power and range, My bike will do 40mph, with 130mile range, and I'm 89kg in weight. Cheers man

 

[khorn]

In Denmark we are allowed to go up to 45 km/h with our Pedelecs so I took an old Specialized Enduro Pro and converted it with a Bafang mid drive. I’m using it for a 60 km commute to work every day. I have an endurance of around 130 km and it works just beautiful on tarmac and fire roads, as an EMTB it is utterly useless.

Karsten

 

[Liquidbarrel]

Hello Bubby
Yeah I agree with the chaps, You need to buy a reasonable donor bike. You usually get a bigger triangle for that big powerful battery if you choose a hardtail. I'll post a photo of the build I've just completed, and if it's of any interest to you then get back to Me with any questions. But as for power and range, My bike will do 40mph, with 130mile range, and I'm 89kg in weight. Cheers man View attachment 9600 View attachment 9601

Thanks creative source...could I ask which motor and battery you went with? Also approx cost (not including bike)? Cheers

 

[CreativeSource 9]

Thanks creative source...could I ask which motor and battery you went with? Also approx cost (not including bike)? Cheers

Hi mate
(Motor) - is a standard DD1500watt. £270
(Battery) - 52v 28ah LG MJ1 cells in hard triangle plastic case 45amp BMS. £450
(Speed Controller) - Sine Wave 45amp. £50
And about another £150 for
Throttle
Pas censor
Re-gen brake kit
KT lcd3 display
Torque arm
£380 donor bike
Hope this helps buddy

 

[Dax]

I've spent a bit of time playing with home builds, had one planned out but never built it in the end. Theres a bunch of pros and cons to home built conversions vs an off the rack emtb.

The bafang works really well for building an electric motorbike, thumb throttle, no limiter, complete giggle. I've taken a mid-drive with the old 750w out in the mud having a hilarious time on stuff that would be no fun on a emtb, throttle open wide, rear wheel sliding around, big rooster tail. The big issue with the bafang is reducing the bottom bracket height, leaving the fragile motor exposed to rocks.

The kenevo rides much more like a mtb than an electric motor bike, much more capable than any frame you'll manage to lash motor and batteries onto, much subtler, better balanced and lots more fun to ride down trails.

I would suggest test riding both types before investing time and money into a home build, it depends what will suit the sort of riding you want to do. At some point I'll build an electric motorbike, but I'm certain that it wouldn't get anywhere near the amount of use that my emtb does.

 

[Janluke]

There are some great builds here and for fireroads, forestry access tracks and mild single track green/blue routes they would be fine. The OP mentions a DH bike. Using a kit on a DH bike to give yourself a powered uplift then hurtling down proper DH routes and I think you'd spend more time rebuilding the kit than riding