Advice on a DIY conversion please..

[PhilYerBoots]

It's been interesting reading about different members DIY projects on here as I'm close to ordering a conversion kit myself to fit either to my older Scott Aspect 45 MTB or a new Giant Roam XR3, both with hydraulic discs.

I want to fit a pedelec sensor rather than throttle only but I don't really want to mess with the drivechain on either bike if I can help it (maybe on the older Scott...).
So with the ease of fitting the kit, a front wheel conversion is sounding best for my technical skills, or rather lack of them..!

Firstly anybody got opinions on which bike would be the best donor for an electric conversion, which I think will be a front Bafang either legal 250W or BPM 350W kit from BMS. Also not sure whether to go for the triangle mounted bottle battery for better weight distribution or a better power/range Ping battery in a rear mounted trunk bag.

I'll be mostly using it for a 10 mile round commute with rear rack and panniers (medium hills) and weekend jaunts on the Wirral coastal path trying to catch up with my wife on her Juicy Classic.

Any advice or opinions on my options would be welcome, especially any additional items I'm likely to need for fitting the kit, (torque arms for the BPM..?).

Thanks.
Phil.

 

[Scottyf]

The bottle battery would work well with a front motor and rear panniers still allowing the bike to have a equal balance.

Its also easier to setup and a little more straight forward. Fitting the pedelec sensor will require a little bit of fiddling on removing one of the crank arms. You will have to do that though as the sensors will not pick up your cycling movement.

If you can afford a ping in a battery trangle bag that maybe an option. It also gives you a nice place to hide the controller.

The bottle battery will be a nice clean installation though and still allow you to use your standard rack.


So long as your not running to high a power you should be able to avoid torque arms. Check if the front forks are aluminium. Mine where cromoloy which worked well and quite strong. Not as strong as steel but a half way house.

Kits are generally easier to install as they usually give you everything you need and then its up to you how you route the installation cables and mount various bits.

If in doubt there are members here always willing to help out.

 

[Deleted member 4366]

Starting with the bikes: I don't think it makes a lot of difference as they have similar layouts and features. The Giant's got a bit more room in the triangle for a battery, which might be useful now or later. It's a lot easier to fit the pedal sensor if you have the square shaft, so check for that. You can fit it on the non-drive side, so you don't have to disturb the drive chain. You only have to mount the magnet disk back to front. You don't have to unrivet the sensor like some have done.
Which motor 250w or 350w: Only you can choose. The 350w requires a bigger, heavier and probably more expensive battery (unless you want to use lipos), so you end up with a heaviier bike that can go up any hill without pedalling.

Bottle batteries are only suitable for the 250w motor and it's not easy to fit a 20aH Ping in the triangle. It might just fit. If you fit a 20aH ping battery on the rack, it upsets the balance of the bike a bit because it has a lot of momentum high up, which makes the bike a bit floppy as you lean it side to side, but I'm happy to put up with that.

The shaft on a BPM is bigger than the 250w motors so you have to do a fair bit of filing of the drop-outs and you definitely need torque arms, which are easy enough to make if you can weld. I can give you info on that later if you need it.

I summary, the 250w motors whether front or rear are a lot easier to fit and give more battery options and makes a lighter bike. If you're fit enough and don't mind puffing a bit up the steep hills, then one should be OK. The 350w motor has more than enough power for all circumstances, but is heavier and more difficult to fit. If you like lazy cycling - that's what you want.

You can improve the hill-climbing of the 250w motors a lot by soldering the shunt in the controller to go up to about 20 amps instead of the normal about 15 amps, but then you need a battery of about 15aH or more or lipos, and your motor probably won't last so long, but they're pretty cheap so that's not really an issue. Also they make a lot more noise like that so it's not so easy to creep up on the lycra boys. The BPM is nearly silent.

Let us know how your project progresses.

 

[PhilYerBoots]

Thanks for your advice Scotty and d8veh...its great to have so many options but it makes the kit and battery choice trickier, with motor power and battery position being the biggies I suppose.
I like the idea of extra hill-climbing power when needed, as I'm pushing 50 and not finding hills any easier to climb, but I do like to put some effort in to keep my fitness up and have been commuting most of the year unpowered.
For those reasons I think I'll be going for the easier fitting 250w kit with a bottle battery, avoiding the need for torque arms (as I can't weld..).
Bearing all that in mind would it be much cheaper to buy the components from BMS or better to go for a UK warranted 8-Fun kit..?
I'm still waiting delivery of the Giant but am favouring that for the conversion once I've had a chance to test ride it for a bit.

Thanks again chaps.

Oh yeah forgot to ask about motor cut-out options for hydraulic brakes...?

 

[Cyclezee]

Hi Phil,

You might wish to consider and eZee conversion kit as a possible option. They are particularly good value at the moment in our end of year sale. There is an eZee kit for almost every application and type of bike or trike.

Regards,

 

[Deleted member 4366]

Seeing as John mentioned it, the Eezee kit is nicely thought out. The motor is bigger and heavier than the average 250w, and I reckon that it'll easily give more power with thw right controller if you find out after installing it that you could do with a bit more.I've heard that the Americans run them at 20mph.

Anyway, you've probably already researched the different kits, so you pay your money and make your choice. To answer your question if the choice is between BMSB or 8Fun, I'd get it from 8fun because the kit is plug-and-play and you get full support. Juicy isn't much more expensive, so if they're nearer, it could be worth it.

Hydraulic brakes are tricky. My conclusion now is the best thing is to change the rear brake to a cable-operated disk and put the cut-out switch on the cable by using a bike computer sensor. You don't really need a hydraulic brake on the back. Alternatively you can buy the Magura brake switches for about £25 each, but I've heard questions over their reliability.

 

[Cyclezee]

Seeing as John mentioned it, the Eezee kit is nicely thought out. The motor is bigger and heavier than the average 250w, and I reckon that it'll easily give more power with thw right controller if you find out after installing it that you could do with a bit more.I've heard that the Americans run them at 20mph.

Just to clarify if I may, eZee kits can be derestricted, but only for off road use!
The latest up-graded eZee controller with a 4110 Mosfet as supplied with kits is capable of reliably handling more power and up to 52 volts.

Regards,

 

[PhilYerBoots]

Thanks again for the advice and suggestions.
I like the look of the Ezee kits John (especially their 'off-road' potential..!) but it would be pushing the budget a bit even at sale prices.
I've spoken to Bob about Juicy's kit but their hub doesn't take a front disc rotor so 'v' brakes only with their kit apparently.
I was worried you might say that about the brakes d8veh. I've always preferred hydraulic as they self-adjust and less hassle so that's thrown a spanner in the works. Doesn't the Daahub kit use switches you can attach to existing brake levers - would these be easy enough to replicate or source from Wisper maybe..?
Too many options and questions in my head...Doh..!
Can't wait though as my new Giant arrives today or tomorrow..just wish the wind would die down a bit or I'll get blown into the Mersey..!

 

[Deleted member 4366]

I forgot to mention that you normally need a disk of at least 180mm to clear the caliper from the motor, so if you have to go up from 160mm, you need a caliper adapter/spacer that costs about £4.
The Daahub kit had some reed switches that went on the brakes. They've delayed the kit and the only guy on the forum that has it has kept very quiet about all the problems with it, so maybe they don't work. They're not available yet anyway. It should be possible to make your own switches if your good at that sort of thing. You only have to make a holder for the switch that cable ties to the lever body.

I still think that the easiest option is to get a used cable caliper from Ebay or wherever and fit it on the rear with a cable switch, so you need a lever (supplied with the kit), cable, caliper and switch (off a bike computer) - £10 max!

 

[JuicyBike]

Hi Phil
We also sell hydraulic brake kits with levers that include hall effect sensor switches, callipers to fit your existing rotors and pipes and fittings. RRP £195, our price £149. Key feature is the very robust brake lever switches, but the price is somewhat more than Dave's £10, which is a great solution!

 

[PhilYerBoots]

Thanks chaps.
Think I'm preferring Dave's solution as well Bob due to cost, although using the Juicy kit I suppose I'd get a few quid back on ebay for my old hydraulic brake set if I did a complete swap out...
Well my new Giant's been delivered today according to my wife so I'll need to try that out first (once the gale force winds die down a bit..!) to decide on my donor bike before I order any kit.

 

[PhilYerBoots]

Quick update...
Unfortunately I think I'm going to have to return the Giant Roam. I wasn't able to find one of these in stock to try at any LBS so took a punt ordering online as Wiggle were selling them less than half price. I ordered a large as I was inbetween M or L frame sizes but the standover height is a bit tight to my gentlemans tackle..!
The larger frame also makes the top tube a bit of a stretch so it just doesn't feel comfortable, even if I were to change stems I think. Shame as its a lovely bike with great components and to get it for under £300 was what seduced me..!
Anyway looking around again I've seen a Giant Expression LX commuter/comfort bike going cheap as well, photo below. This is setup for comfort rather than speed, which I know my sore back would appreciate having commuted the past couple of days following a 2 week break.
Any opinions on the suitability of this bike for a conversion..?

 

[Cyclezee]

Hi Phil,

Sorry to hear the Giant Roam was a bit on the big side, obviously seat and handlebar heights can adjusted, but not the crossbar. Hopefully, Wiggle will take it back without too much hassle.

The Expression LX would be quite suitable for a 700c front or rear wheel eZee conversion.

Regards,

 

[banbury frank]

Hi Phil

I have a Ex demo Express For sale done about 30 miles on demos

It is a Raleigh Metro LX 18 inch frame 48Volt 10ah battery

Price £1100 £300 off rrp

Raleigh - Pioneer Metro LX Mens

Xipi Electric Bike Conversions > The Express - Ready to Ride

Please come for a demo ride we are open 7 days a week


Frank

 

[PhilYerBoots]

Wiggle have a 7 day returns policy, legally required for distance sellers I believe, but I'll have to pay £20 to return - you pays your money and takes your chance I suppose..
Your kits are still a bit above my budget John and although your Rayleigh is a good price and looks same spec as the Giant Frank (apart from fixed fork instead of suspension..) I'm still favouring doing my own conversion but keeping costs down.

 

[JuicyBike]

The Expression LX commuter looks OK to convert Phil. It's a 28" right? You just need to check the distance between the drop-outs.

 

[PhilYerBoots]

Yes it's a 28" wheel Bob. While I prefer disc brakes it ticks most other boxes and makes the fitting of a brake cut-off switch easier. I'll try and find some specs online for drop-out clearances if/before I buy it, maybe on fork manufacturers website, its an RST SOFI 50mm.

 

[Cyclezee]

If you haven't already checked Phil, the fork specs are here RST all that is apart from the one you need, dropout width .

You could ask the bike supplier to measure them for you. My guess is they will be 100mm, but better to be safe than sorry.

What ever kit you decide on, good luck with the conversion.

Regards,

 

[PhilYerBoots]

Thanks for the link John.
I suppose they don't see dropout clearance as a deciding factor when it comes to selling forks, which unless you are looking to convert a bike isn't that relevant I suppose...
Wiggle are collecting the Giant on Monday and we'll be happy to get our hallway back in time for christmas visitors so will be putting conversion plans on hold now 'til the new year.

 

[Cyclezee]

Hi Phil,

It is good that Wiggle are taking the Giant back.

Let me know in the New Year if you are interested in an eZee conversion, in the meantime have great Christmas

Regards,