NEWB conversion ponderings

czgunner

New Member
Region
USA
Hey everybody.
My wife and I moved away from the West coast and now live in beautiful, quiet, WY. I can't express how much we love it here.
I bought a couple of pedal bikes last year for us.
My wife had a quick, flat ride to her work, but she is being transferred a few miles down a very steep hill. She asked about converting her bike to electric. It has v brakes and I decided instead to buy her a new Ride1up Core 5. I'm sure she'll be able to get up the hill much easier now. She doesn't expect to throttle up the hill, rather she wants to still get a workout with some assist.
That got me thinking about maybe converting my Rock Mountain Fusion 10 29'er. There are so many kits, and to be honest most look a bit shady. I look at some of the "high end" kits and they exceed the value of my bike. Not sure if it's worth converting mine or not. I was an auto mechanic for 11 years and wouldn't have any problem installing one.
Any thoughts would be appreciated.
 
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indianajo

Well-Known Member
The cheapest kits are direct drive. Those are not suitable for climbing steep hills. They will do it but consume way too many watthours compared to geared hubmotor kits. Geared hubmotor kits will not climb 1000' in an hour without risk of overheating. You live in WY, be warned. I climb 80 hills with mine in 3.7 hours, but none longer than 100' rise.
Sleaze in the kit regime involves parts falling off or rubbing. I haven't run into it, but others have.
Corners cut include heat not transferred from the controller transistors to the beautiful aluminum heat sink. Also capacitors that leak like sieves. So far the latter, they all do it. The worst panasonic/nichicon/rubicon/kemet capacitor sold at newark or digikey is miles better than the garbage that comes in ebike controllers. The newest feature is potted controllers, so when the capacitor finally burns through, you buy another controller. New for 2022 at grin. I've taken my screwed together controllers apart and replaced the capacitors so they don't spark the battery connection the 2nd time when I unplug and replug them. I've also added heat sink compound between transistor bar and the beautiful, previously non-functional aluminum case.
Here is a thread the discusses semi-reliable kit vendors.
I'd add to that list leaf & greenbikekit . Both have retreated to Asia, so if you want one you have to give aliexp your birthdate. Grin is expensive and in Canada, which got some shipments held up in customs for 13 weeks for one ebr poster.
 

czgunner

New Member
Region
USA
My wife loves her Ride1Up Ebike.
I'm pretty sure I want to convert my RM Fusion 10 to a mid drive.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
My wife loves her Ride1Up Ebike.
I'm pretty sure I want to convert my RM Fusion 10 to a mid drive.
If you're in an area with a lot of hills, that's very likely the better plan. Mid drives are pretty versatile with little downside if you enjoy doing your own work.

If going DIY, my choices would be between the Bafang BBSHD for it's rock solid reputation and the TSDZ for it's torque sensing ability.

I've built a couple of successful bikes, but have been riding e-bikes (daily) long enough now where there is little doubt I'll be riding as long as I'm able. Point being, it's pretty easy for me to justify the money spent on "just the right bike". I now prefer the clean look of a bike with a built in battery, and disk brakes are an absolute must. I bring this up, because I would buy a production bike chosen for it's good bones (motor of choice, battery size, frame size, and wheel size), with plans to change it to my 'druthers (spoiled rotten - whatever it takes!). Tire brand and size, seat, suspension seat post, handlebars & grips all will be added or changed. Bike WILL have a throttle. Not negotiable..... -Al
 

m@Robertson

Well-Known Member
Region
USA
If you are doing hills, go with a mid drive. Its the motor type that is not at an inherent disadvantage in that terrain. I looked up your bike. Framewise it appears pretty much perfect for a mid drive conversion, but you are going to want to look at the chainstay root since its a 1x drivetrain. You need a certain amount of clearance to get the secondary gear housing tucked in.

More details on that are here:

I would recommend a BBSHD, and then dial it back via a programming cable/laptop or config tool. You'll have an overbuilt motor running at a fraction of its capacity, so it will last forever.
 

EMGX

Well-Known Member
Consider measuring the chainline (middle of seat tube to your chainring) and compare to the chainline you will get with an aftermarket mid drive. Here is quote from eco-ebike
"Note: The Stock 42T w/ Guard is dished/offset 5mm for a chainline of approx 51mm. With out the stock chainring, the chainline is approx 56mm on the inside, and 61mm on the outside if you have a double"
I haven't seen a bafang mid drive in person but it seems that the chainline displacement must be similar(ly bad) with cross chaining in the lowest gears. I don't see this mentioned as much as (I think) it should. something to look into if you plan to use the lowest/largest few cogs of your cassette.
 

czgunner

New Member
Region
USA
Here are some pics.
I'm concerned about the chainring. I'm not sure I can go much bigger than what I have now. Anybody who knows mid drives might have some input?




 

tomjasz

Well-Known Member
Region
USA
City
Minnesnowta
The cheapest kits are direct drive. Those are not suitable for climbing steep hills. They will do it but consume way too many watthours compared to geared hubmotor kits. Geared hubmotor kits will not climb 1000' in an hour without risk of overheating. You live in WY, be warned. I climb 80 hills with mine in 3.7 hours, but none longer than 100' rise.
Sleaze in the kit regime involves parts falling off or rubbing. I haven't run into it, but others have.
Corners cut include heat not transferred from the controller transistors to the beautiful aluminum heat sink. Also capacitors that leak like sieves. So far the latter, they all do it. The worst panasonic/nichicon/rubicon/kemet capacitor sold at newark or digikey is miles better than the garbage that comes in ebike controllers. The newest feature is potted controllers, so when the capacitor finally burns through, you buy another controller. New for 2022 at grin. I've taken my screwed together controllers apart and replaced the capacitors so they don't spark the battery connection the 2nd time when I unplug and replug them. I've also added heat sink compound between transistor bar and the beautiful, previously non-functional aluminum case.
Here is a thread the discusses semi-reliable kit vendors.
I'd add to that list leaf & greenbikekit . Both have retreated to Asia, so if you want one you have to give aliexp your birthdate. Grin is expensive and in Canada, which got some shipments held up in customs for 13 weeks for one ebr poster.
OFFS! I’ve sold and ordered a number of kits from them. Never a problem, with MANY ORDERS!
Expensive? Not if you don’t want to spend hours online looking for help.
 

tomjasz

Well-Known Member
Region
USA
City
Minnesnowta
You’ve been busy searching! All I can find in my lists are older version of RM conversions. With either a BBSHD or BBS02B a small chainring shouldn’t preclude a conversion. IF it’s a 73mm bottom bracket a conversion chainring of the same size oughta by fine. There are some BBSxx conversion measuremen charts out there. I’m looking for my copies. I’m thinking I posted them here on EBR...

All I have logged is a BBSHD on 2006 Rocky Mountain Element 50.

Id stick with the same size chainring. The BBSHD is a tough motor. Capable of still being a great performer with the OEM size chainring.

Google BBS02 installation measurements

bbs02 installation measurements - Google Search.png
 
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PedalUma

Well-Known Member
Region
USA
City
Petaluma, CA
The right chain stay kicks out quickly to accommodate the wide tires. If spacers are added that means more offset in the wrong direction. I had one last week that did not need spacers to the left but it couldn't hit cogs 1 and 2. A 10mm offset chainring took care of it by bringing in the chain line. But then on your bike it could rub the chain stay. This is a tough one for me to call online. Look up ^ to see the red circles. This is not a perfect example but you still get the idea.
 

PedalUma

Well-Known Member
Region
USA
City
Petaluma, CA
I relooked. A key number is 60mm. The motor needs to be at a flat at 90 degrees from the R and center of the bb shell towards the back of the bike for 60mm. That is the distance of three outer chain links. Counting back three links it hits. You can test by removing the cranks and bb and laying a straight edge on the R shell of the bb. How far back before it hits the chain stay from the rotational center of the bb? Please others join in. I don't want to go out on a limb with this.
 

czgunner

New Member
Region
USA
I relooked. A key number is 60mm. The motor needs to be at a flat at 90 degrees from the R and center of the bb shell towards the back of the bike for 60mm. That is the distance of three outer chain links. Counting back three links it hits. You can test by removing the cranks and bb and laying a straight edge on the R shell of the bb. How far back before it hits the chain stay from the rotational center of the bb? Please others join in. I don't want to go out on a limb with this.
OK cool. I have a BB socket coming Monday (what happened to Amazon prime 2 day delivery?) and I'll pull it apart and check it then.
 
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PedalUma

Well-Known Member
Region
USA
City
Petaluma, CA
@czgunner, This is not a perfect example. The bike is dirty. It is a different mid-drive. But, it does illustrate the issue. In this case three inner links of chain (60mm) back from the center of the bottom bracket, the motor housing cannot hit the chain stay. This particular motor is slightly smaller than the BBSO2. Again, it is only the concept illustrated and with a different bike than yours. Having a white bike sure helps the the contrast problems with black on black. Why do they always put the black S on the black S with the Black S? It happens all the time. Even when you shine a light, it is a F-ing black hole to try to work on. Then some bitty black screw drops down lost. A forever rattle?
 

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