The conversion is not hard it’s just a little time consuming and awkward to do. It will test your patience
Please note that the following is for informational purposes only. It is what we did to convert our ELF to the newer Updrive 3-chain system because our NuVinci axle broke when it was on the Rear Wheel. We assume no responsibility for any installations to correct the NuVinci Axle breaking problem.
The Updrive is a 3 chain system. It is the current standard on all newer ELFs. In the updrive system the motor and geared hub (NuVinci CVT) are mounted under the seat. This up drive system has 3 bolt on cogs. They are available online and made by Surly or Problem Solvers.
Two additional ELF “Sliders” are needed to make this conversion. They can be purchased new from Organic Transit. Many times you can find used Elf parts for sale from the classified section of Anyone Can Bike. Always check there first.
The motor connects to the right side of the rear wheel with a 3/32″ chain. The rear wheel has a 22 tooth ACS Crossfire freewheel on it. The cog on the motor is an 18 tooth bolt on cog.
Geared Hub Chain
The mid drive geared hub (NuVinci) is connected to the left side of the rear wheel with a 3/32″ chain. The rear wheel has a 20 tooth bolt on cog and a spacer to keep the chain away from the rotor of the disc brake. The chain is goes to an 18 tooth bolt on cog on the left side of the NuVinci. There is a spacer between the cog and the NuVinci.
Inorder to use the motor from the rear wheel hub setup it will need to have the cog removed and placed on the other side or have the motor reverse directions. The motor and chain drive will be on the opposite side from where it currently is and spinning the opposite direction. We happened to have another motor and just placed the new cog on it instead.
The right side of the NuVinci has an 18 tooth threaded cog with a 3/32″ chain that goes to the pedal chain ring.
Assuming the NuVinci still has its 18t freewheel Cog, remove the Bolted on Freewheel. Ours was a 27t DICTA.
1-Surly Single Cassette Cog 3/32”22t freewheel for the right side rear wheel- Bikeman.com
1-Surly Single-Speed Kit, Spacers and Lockring- Bikeman.com
1–Single Speed 20t Bolt on Cog for the left side rear wheel – Problem Solvers
1- Booster Conversion Kits – Problem Solvers
1- Single Speed 18t Bolt on Cog for the right side of the Motor (remove and discard the old screw-on Cog) – –Problem Solvers
1-18t Bolt on Cog for the left side of the NuVinci
1-12 x 142 TA 36-hole cassette Hub – Bikeman.com
1-12mm x 190mm Bolt- Bikeman.com
1-Bumax 88 M12 stainless nut- Bikeman.com
1-set M12 shim washers – Bikeman.com
4-sets of SRAM PC1 Nickel 114 Link/330g Single Speed 3/32 Bike Chain , other chains can be used –Performance Bike
Organic Transit made an Updrive Kit at one time. This shows the parts for it including Motor and NuVinci. This kit is no longer sold by Organic Transit.
Remove the seat.
Disconnect and remove the Disk Brake, Wheel Slider, Body Mount Sliders (You will need to suspend and support the body when you remove the sliders), Wheel Tensioner, Cross member Bracket and Motor Slider.
Remove the Tray. It will have to be shortened and put back.
The pair of sliders that mount the new rear wheel and 12mm bolt will probably need to be drill out and enlarge to accomodate the new 12mm bolt.
Then install the new Slider for NuVinci, then Body Mount Sliders, the Motor Slider with Chain Tensioner attached, the Cross member Bracket and finally the Wheel Slider.
Cut the Battery Tray to the size you need at the back end and replace the tray.
Re do spacing on Disk Brake Mount for proper alignment
Mount the Second Chain Tensioner for the Pedal Ring to NuVinci at the Tray.
Our Diagram for the Updrive
12 x 142 TA 36 hole Cassette Hub
(Note, we had a bike shop drill out the hub and wheel then relace it with 13 gauge spokes. We hope this will add more strength to the rear wheel.)
Our Up Drive Conversion 3-Chain Images
Tray Cut for Up Drive. The Tray needs to be Shortened to accommodate the NuVinci
Overall NuVinci, Motor and Rear Wheel
Close up of NuVinci mounted ahead of the Motor
Brackets and NuVinci and Motor mounts
Right side of Rear Wheel with Freewheel Left side of Rear Wheel
This is not a difficult modification, but it is time consuming. The uniqueness of the ELF makes the modification awkward and tests ones creativity to the limits at time, but the outcome is amazing. Our ELF “Shelby” runs better, faster, and has far less problems or repairs after this conversion.