Browneye
Well-Known Member
In another thread here - Turning Your bike into an Electric Bike - I posted a lot of detail and got a ton of questions answered in making this conversion. And I often get inquiries and comments, and it seems there are others doing the same to this or similar pedal bikes, so let's have a thread just for this - I'll post what I learned, and some pics and then we can have a Q&A place for this project for any newcomers.
I had a lot of questions when contemplating this conversion and @stanmiller and @Thomas Jaszewski and @harryS were a great wealth of information. And due to Stan's success with importing from China from the same company, it gave me the confidence to jump into it.
The Roll is a particularly good candidate for a conversion due to it's relaxed ergos, balloon tires, disc brakes, and it's a really solid bike. Plus the Bafang geared hub and wheel assembly simply drops right in without any modifications or challenges.
I got this kit: https://www.amazon.com/gp/product/B07P736XGM/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&th=1&psc=1
Just to fill in details for when or if it becomes unavailable, this is a Bafang 500w geared hub, the larger housing - 170mm overall diameter. There are a lot of kits out there with the smaller 158mm hub. My thought was the bigger hub would have bigger gears and over all more heavy duty, so more appealing. I don't know for sure or not, but seemed logical. My assumption is this larger hub is the same one they use for their 750w offering. Hailong 11.8ah battery with Panasonic cells, C961 display, 27.5" wheelset with Freewheel cassette.
This amazon/ebay/aliexpress seller - Greenergy whom is a distributor for Bluenergy products. The latter sells on AliExpress. The advantage with the former is they have a warehouse/office and support line in Las Vegas, so state-side, but no one is clear if they actually answer the phone and/or can provide actual assistance or warranty coverage. Seems like a good idea though, lends confidence.
They also purport to spec Panasonic cells in their batteries which lends confidence to usability and performance. So far we're more than thrilled with our setup. We got the Hailong ('tube') battery in the 12ah size - seems to be good for about 40-50 miles or so. If you're looking for longest range the 17ah battery is a good option and relatively inexpensive when spec'ing it up front. The Hailong case bolts right up to the bottle carrier bosses on the downtube on the Roll - easy-peasy. The rear rack battery is another option, but frankly the way the Hailong sets up on the downtube I would recommend it. The Hailong case has been updated with better battery connection contacts, and a more sturdy metal mounting plate.
I opted for the plain-jane C961 display, it's the cheap one, and really, it works just fine. Some of the fancy color displays are over-kill in my opinion - all you really need is your charge level and a quick look at your assist level, and then speedo and odo - they all do this. The trends are actually moving away from a fancy display - kind of overkill for an ebike. In any case, choose which one you think you would like for your kit. The Hailong case does have a USB port for charging your phone on your ride.
The Roll has a 7-gear Freewheel cassette, so if you're spec'ing another kit keep this in mind. The one linked above has a Shimano cassette in the box - you simply screw it on to your geared hub, and change the disc from your stock hub to the new hub-drive. They provide different (shorter) screws - use those as the stock ones are too long. If you get a hub without a cassette you'll need a chain-hold tool and freewheel socket tool to remove your stock one and install on the new hub. I liked the idea of a complete wheel and gear assembly so if something happened to the hub drive I could simply just swap the whole thing back to stock.
It is pretty well accepted that disc brakes are a necessity for an ebike, so the Roll models with either cable or hydraulic discs is recommended. If you have hydraulic brakes, or integrated shifter/brake lever units, you'll want to specify 'brake sensor cables' in lieu of bafang brake handles. They work fine, easy to install - as soon as you grab for either brake it kills the motor assist.
I have one setup that way because our Roll has integrated shifter/brake all in one. I did remove the left shifter and used the bafang brake handle, sourced a single-chain crankset - it simplified the bar setup, got rid of the clutter at the crank. In our case the wife never shifted the front deraileur anyway, and now with assist it's a foregone conclusion. I can provide a link for that if you're interested - several options for about $50 for a nice single-ring crank set with 170mm arms (stock length). Otherwise setting it up with the stock gearing is just fine - the elite and sport models come with 28-38-48 chain rings - I opted for a 42T single and it's perfect for her. If you like a little more speed then a 44 or 46 makes sense. She's happy with about 20mph, mostly cruising about 16-18. I have also ordered a seperate Shimano 7spd trigger-shifter so I can use the other brake handle from the kit - ours has cable actuated discs. For hydraulic brakes you'll want the magnetic sensors for sure.
You'll also need a bottom-bracket tool so you can remove the crank, the crank arms and the actual crank, so you can install the pedal sensor - either will work once you get it apart, but really I think the metal ring sandwiched in the bottom bracket bearing set is a really clean setup. And it works really well. There are two tools - one removes the crank arms, the other the bearing rings in the bottom-bracket. I was able to tap loose the set rings without the spline tool, shade-tree mechanic style. The tools are pretty cheap and makes the job cleaner and easier. You could also have your LBS remove these for you for a fee. Same for removing a freewheel cassette.
The rim they provide is pretty narrow - so setting the balloon 2.3" rear tire up on it is a bit of a trick, but do-able and works fine once it's aired up. Also the spokes are black with bright nipples, whereas the stock (front) spokes are bright SS. Oh well, only YOU will notice it.
The whole hub and wheel assembly is a drop-in fit, right into the chain-stay axle tabs. Use the little keeper washers with the tabs to lock the new hub axle into the frame slots. Unfortunately you lose your quick-release skewers on the rear, so be sure to carry a 17mm wrench should you need to remove the assembly to replace or repair a flat.
I also sourced a smaller controller box and installed it on the seat-post tube - a suggestion from StanMiller. The one that comes with it is fine, but more bulky, and you end up filling in your step-thru space quite a bit. It still works, just a bit higher step. For a non-step-thru Roll this is a non-issue.
As far as performance, it's amazing, and very quiet. You can limit the top speed to whatever you want - I have hers set at 22mph max, which is plenty fast for her - she walks away from my Giant Explore, a Class 1 mid-drive. But you can set it all the way to 32mph max. 30mph on a Roll is mind-boggling LOL, but it will do it!
The only caveat so far is that when you turn it on it defaults to PAS level 1, which is about 10mph. So if you leave it there, as soon as you start pedaling it takes off. And I mean it TAKES OFF!! This is a common complaint with bafang hub drives, like the Aventon Pace bikes, so I have taught her to set it to '0', start pedaling, and then switch the control button to PAS 1. It only took her a few miles to get it down. You basically use the PAS level setting like a gear-shifter - the higher it is from 1 to 5 the faster it goes. Level 3 is about 15-18, level 5 is full power.
We've only put a few hundred miles on our bikes, but so far it works just dandy. A 25 mile ride with some pedaling uses about 40% of the battery. We have not run it all the way down. We used to ride about 10-12 miles with our pedal-only bikes, now easily doubling our range ability with assist. Just fantastic!
Shipping can take about 3-4 weeks out of China for these kits. The battery ships separately and they say can take longer, but we got our battery first, then waited another week for the kit. It comes nicely packaged with everything foam-packed. They really do a nice job on these.
The ROLL is such a great little bike, and this is a really clean install. Every bike shop we've been to, they have been really impressed with my install, and surprised it was a DIY conversion.
I had a lot of questions when contemplating this conversion and @stanmiller and @Thomas Jaszewski and @harryS were a great wealth of information. And due to Stan's success with importing from China from the same company, it gave me the confidence to jump into it.
The Roll is a particularly good candidate for a conversion due to it's relaxed ergos, balloon tires, disc brakes, and it's a really solid bike. Plus the Bafang geared hub and wheel assembly simply drops right in without any modifications or challenges.
I got this kit: https://www.amazon.com/gp/product/B07P736XGM/ref=ppx_yo_dt_b_asin_title_o05_s00?ie=UTF8&th=1&psc=1
Just to fill in details for when or if it becomes unavailable, this is a Bafang 500w geared hub, the larger housing - 170mm overall diameter. There are a lot of kits out there with the smaller 158mm hub. My thought was the bigger hub would have bigger gears and over all more heavy duty, so more appealing. I don't know for sure or not, but seemed logical. My assumption is this larger hub is the same one they use for their 750w offering. Hailong 11.8ah battery with Panasonic cells, C961 display, 27.5" wheelset with Freewheel cassette.
This amazon/ebay/aliexpress seller - Greenergy whom is a distributor for Bluenergy products. The latter sells on AliExpress. The advantage with the former is they have a warehouse/office and support line in Las Vegas, so state-side, but no one is clear if they actually answer the phone and/or can provide actual assistance or warranty coverage. Seems like a good idea though, lends confidence.
They also purport to spec Panasonic cells in their batteries which lends confidence to usability and performance. So far we're more than thrilled with our setup. We got the Hailong ('tube') battery in the 12ah size - seems to be good for about 40-50 miles or so. If you're looking for longest range the 17ah battery is a good option and relatively inexpensive when spec'ing it up front. The Hailong case bolts right up to the bottle carrier bosses on the downtube on the Roll - easy-peasy. The rear rack battery is another option, but frankly the way the Hailong sets up on the downtube I would recommend it. The Hailong case has been updated with better battery connection contacts, and a more sturdy metal mounting plate.
I opted for the plain-jane C961 display, it's the cheap one, and really, it works just fine. Some of the fancy color displays are over-kill in my opinion - all you really need is your charge level and a quick look at your assist level, and then speedo and odo - they all do this. The trends are actually moving away from a fancy display - kind of overkill for an ebike. In any case, choose which one you think you would like for your kit. The Hailong case does have a USB port for charging your phone on your ride.
The Roll has a 7-gear Freewheel cassette, so if you're spec'ing another kit keep this in mind. The one linked above has a Shimano cassette in the box - you simply screw it on to your geared hub, and change the disc from your stock hub to the new hub-drive. They provide different (shorter) screws - use those as the stock ones are too long. If you get a hub without a cassette you'll need a chain-hold tool and freewheel socket tool to remove your stock one and install on the new hub. I liked the idea of a complete wheel and gear assembly so if something happened to the hub drive I could simply just swap the whole thing back to stock.
It is pretty well accepted that disc brakes are a necessity for an ebike, so the Roll models with either cable or hydraulic discs is recommended. If you have hydraulic brakes, or integrated shifter/brake lever units, you'll want to specify 'brake sensor cables' in lieu of bafang brake handles. They work fine, easy to install - as soon as you grab for either brake it kills the motor assist.
I have one setup that way because our Roll has integrated shifter/brake all in one. I did remove the left shifter and used the bafang brake handle, sourced a single-chain crankset - it simplified the bar setup, got rid of the clutter at the crank. In our case the wife never shifted the front deraileur anyway, and now with assist it's a foregone conclusion. I can provide a link for that if you're interested - several options for about $50 for a nice single-ring crank set with 170mm arms (stock length). Otherwise setting it up with the stock gearing is just fine - the elite and sport models come with 28-38-48 chain rings - I opted for a 42T single and it's perfect for her. If you like a little more speed then a 44 or 46 makes sense. She's happy with about 20mph, mostly cruising about 16-18. I have also ordered a seperate Shimano 7spd trigger-shifter so I can use the other brake handle from the kit - ours has cable actuated discs. For hydraulic brakes you'll want the magnetic sensors for sure.
You'll also need a bottom-bracket tool so you can remove the crank, the crank arms and the actual crank, so you can install the pedal sensor - either will work once you get it apart, but really I think the metal ring sandwiched in the bottom bracket bearing set is a really clean setup. And it works really well. There are two tools - one removes the crank arms, the other the bearing rings in the bottom-bracket. I was able to tap loose the set rings without the spline tool, shade-tree mechanic style. The tools are pretty cheap and makes the job cleaner and easier. You could also have your LBS remove these for you for a fee. Same for removing a freewheel cassette.
The rim they provide is pretty narrow - so setting the balloon 2.3" rear tire up on it is a bit of a trick, but do-able and works fine once it's aired up. Also the spokes are black with bright nipples, whereas the stock (front) spokes are bright SS. Oh well, only YOU will notice it.
The whole hub and wheel assembly is a drop-in fit, right into the chain-stay axle tabs. Use the little keeper washers with the tabs to lock the new hub axle into the frame slots. Unfortunately you lose your quick-release skewers on the rear, so be sure to carry a 17mm wrench should you need to remove the assembly to replace or repair a flat.
I also sourced a smaller controller box and installed it on the seat-post tube - a suggestion from StanMiller. The one that comes with it is fine, but more bulky, and you end up filling in your step-thru space quite a bit. It still works, just a bit higher step. For a non-step-thru Roll this is a non-issue.
As far as performance, it's amazing, and very quiet. You can limit the top speed to whatever you want - I have hers set at 22mph max, which is plenty fast for her - she walks away from my Giant Explore, a Class 1 mid-drive. But you can set it all the way to 32mph max. 30mph on a Roll is mind-boggling LOL, but it will do it!
The only caveat so far is that when you turn it on it defaults to PAS level 1, which is about 10mph. So if you leave it there, as soon as you start pedaling it takes off. And I mean it TAKES OFF!! This is a common complaint with bafang hub drives, like the Aventon Pace bikes, so I have taught her to set it to '0', start pedaling, and then switch the control button to PAS 1. It only took her a few miles to get it down. You basically use the PAS level setting like a gear-shifter - the higher it is from 1 to 5 the faster it goes. Level 3 is about 15-18, level 5 is full power.
We've only put a few hundred miles on our bikes, but so far it works just dandy. A 25 mile ride with some pedaling uses about 40% of the battery. We have not run it all the way down. We used to ride about 10-12 miles with our pedal-only bikes, now easily doubling our range ability with assist. Just fantastic!
Shipping can take about 3-4 weeks out of China for these kits. The battery ships separately and they say can take longer, but we got our battery first, then waited another week for the kit. It comes nicely packaged with everything foam-packed. They really do a nice job on these.
The ROLL is such a great little bike, and this is a really clean install. Every bike shop we've been to, they have been really impressed with my install, and surprised it was a DIY conversion.
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I replied that was fine so maybe I'll have a handful of these as back up. LOL
