Tips for commuter-to-ebike conversion using internally geared hub?

[MatthewLeonard]

Hi, I’m new here. Being new to ebikes, I’m wary of building one myself – seems like it could get too complicated and it would take a lot of time and research to make sure I do it right. I’ve found a few good deals on complete bikes, and I’ll probably choose one of them. But the main reason I’m considering building one myself is that I think I would really like to have an internally geared hub, so I don’t have to worry about cleaning and adjusting a typical derailleur over time. I’ve searched and found a few whole ebikes for sale with IGH, but none in the lower price range that I’m looking at (trying to not spend more than $1500 USD).

So…if I did build an ebike with IGH, I suppose I would do a conversion with my current bike: a 2014 Bianchi Cortina. I like its relatively lightweight frame, and I recently had a new fork put on it with suspension. I’m wondering how feasible this would be, what parts I would need to install/replace, and how much it would end up costing me.

Would I need new wheels to be compatible with a conversion such as this?

If I put an IGH on the rear wheel, does that mean the motor has to be mid-drive or on the front hub?

Would a battery mount on the tube using the same holes where my bottle holder is currently attached?

Would I be able to reuse the cable and shifter that currently connect to the rear derailleur? (and I guess just remove the cable and shifter for the front derailleur?)

Any more basic parts I would need in addition to motor, IGH, chain, wires, battery…? Probably a display to mount on the handlebar?

The bike I’m looking at now has a 350w 36v motor up to 20 mph with pedal assist (which I feel like would probably be good enough). So I’d want a system at least as powerful as that, but more power/speed would be nice.

I suppose I’d need to have a plan and make sure I have all the parts I might need delivered in hand, and then devote a weekend to getting it built, as I rely on my bike to commute during the week. I’ve looked at a few forums and instantly felt overwhelmed – I’m sure I could figure out how to do it, but it feels like I would be going down a huge rabbit hole that would suck up too much time and have my wife feeling like I’m not spending any time with her!

I’m sure it might be difficult to answer these questions without seeing the bike in person, but any advice you might have to get me started would be helpful!

Pic of current bike is attached.

Thanks!

 

[Ravi Kempaiah]

so I don’t have to worry about cleaning and adjusting a typical derailleur over time.

Entirely depends on how many miles you are going to ride/year. Derailleur systems have evolved a lot and the latest Shimano XT derailleurs don't need adjustments often. Perhaps once in 6-8 months or more depending on your mileage. I had Shimano Deore derailleur that was tuned only once a year at 4000 miles and it was a mid-drive.

If I put an IGH on the rear wheel, does that mean the motor has to be mid-drive or on the front hub?

That is correct, Only mid-drives or front hubs.

Would a battery mount on the tube using the same holes where my bottle holder is currently attached?

You may need to use RIV nuts and drill an extra hole to secure your battery more firmly.

but none in the lower price range that I’m looking at (trying to not spend more than $1500 USD).

IGH like Nuvinci can be purchased for $150: https://www.bike-discount.de/en/buy/nuvinci-n380-cvp-disc-drivetrain-36-hole-809130

and paired with something like Bafang BBS02 can be a good way to go: https://lunacycle.com/bafang-bbs02-750w-middrive-kit/

You will find several bike builds very similar to yours here: https://lunacycle.com/gallery/

 

[MatthewLeonard]

Thanks for the tips, Ravi. Good to know!

 

[harryS]

With an IGH, it's mid drive kit or front hub motor. Suspension would rule out a front hub motor for me. No need to add risk where none exited before.

Mid drive isn't too hard if you know how to remove cranks and axle on your bike. The subsequent install is straight forward, and the only creative thinking required is where to put the battery, so that it doesn't look like a wart. You'll need to either shorten/lengthen the chain, so a chain tool, master link and maybe some extra links are needed.

You need some electrical skills to connect the battery cable to the motor. like knowing how to either crimp or solder. Regular bike skills to move the brake levers, grips, and shifter assemblies around on the handlebars.

If you lived near Oswego, IL, Mike's E-bikes says he wil install a middrive for $100 if you buy his kit. That kind of shows the labor needed. Around two hours if you know how.

 

[MatthewLeonard]

On a related note, I read this over at https://www.sheldonbrown.com/no-derailers.html#vertical:

It is very desirable that a frame for use without a rear derailer have "horizontal" rear dropouts ... This allows you to move the axle back and forth as needed to adjust chain tension, making things much easier than if you try to convert a newer bike with vertical dropouts ... but there are workarounds with vertical dropouts.

Has anyone dealt with this issue? Looks like the best suggested workaround is adding a chain tensioner.

 

[MatthewLeonard]

he will install a middrive for $100 if you buy his kit. That kind of shows the labor needed. Around two hours if you know how.

Paying a local shop to install might be the way to go. If I did that, I guess my main concern would be making sure I have all the necessary parts to begin with...

So I'm wondering, what parts might I need that wouldn't be included in most kits?

 

[harryS]

Ahhh, I thought your red bike already had the IGH and the requisite chain tension in place. That does make it more work.

 

[MatthewLeonard]

Ahhh, I thought your red bike already had the IGH and the requisite chain tension in place. That does make it more work.

Right, I'm thinking of adding an IGH as well as converting to electric at the same time.

 

[MatthewLeonard]

I just called a couple bike shops in my area to see if they would do the install out of curiosity. One said no, they don't have the expertise. Another said their policy is they won't do a conversion with a bike that is not already designed to be an ebike - and one reason is that the frame may not be designed to handle the torque and wear over time...which is kind of discouraging me from doing this at all now, since my current frame is relatively light.

 

[harryS]

I would agree with the bike shops. Not a lot of money to be made and problems could arise.

Then again, I put a mid drive BBS02 750W on an old Diamondback Wildwood from Dicks Sporting Goods. Not worried about it busting up under me. Hardly ever use more than 300W.

 

[indianajo]

Lightweight bikes are not good candidates for electric conversion. Plus your schedule of one weekend is optimistic at best. Certainly won't fit into the schedule of a bargain job by a local shop.
For converting, I'd visit a charity resale shop or flea market and get a used steel frame bike, middleweight. You may find one with suspension for about $75. Without, about $50, around here. I'd still put torque arms on a hub motor. If you really want IGH I would not buy a mid drive. See grintech's video about doing a conversion up in general discussion. https://electricbikereview.com/forums/threads/why-an-ebike-kit.27333/ The only IGH he recommends with mid drive is the $1000 rohloff. If you get a 7 speed derailleur, you can fit in a rear hub motor in some cases. If the dropout (cleavis) is 130 mm. Note hub motors do not fit many slots, you may have to grind one out with a 4 1/2" angle grinder. Use safety glasses. I did. PAS doesn't fit one piece cranks without major mods, so look for something with detachable crank arms. Then if you don't like the actual used bike frame you can move up later after you know what you are doing. Carbon fiber and aluminum front forks are not candidates for hubmotors IMHO.
Batteries can be hung in a bag from a top rail, but I view that as an invitation to theft. Easy snap on, easy snap off. Mine is in a screw on aluminum frame mount on the front left. Doesn't look like a battery, does it? Stealth is good, IMHO.
I converted the bike left for $830 with a 48 v 17.5 AH luna battery. Direct drive 1000 w motor from e-bay. Do not buy a battery from e-bay or amazon, I received two boxes of garbage.
If you don't stretch the chain all the time with mid drive motor torque, you don't have to worry about it stretching all the time. I get more stretch in my shifter cable than the drive chain. Time to adjust it again, I'm missing 2nd some times. I usually wear the tips off the middle sprockets long before the chain stretches. About 10000 miles I guess.
I bought an IGH before the motor kit, and nobody would tell me which spokes to buy. Once I had the dimensions from the sheet in the box, the spoke calculator got it wrong too. I sent one set of spokes back to the people that sold me the IGH, and threw another away before I got it right. I could have gotten the LBS to lace in the IGH for $110, he has a spoke rethread machine. Nobody sells spoke threading dies. just a whole machine with electric motor for $1000. Use at a minimum Swiss DT spokes, not Wald. I have an opinion about steel tensile strength from a certain very common source of supply. I got 100 extra length spoke nuts from niagara but they went out of business. Modernbike competitive-cyclist and jenson-us don't bother with that useful stuff, just pretty accessories.
I've used ~1000 W up a mile long 10% grade in the next county. The faster one goes with a DD drive upgrade, the less it heats up. Plus no cars passed me.