Utah Trikes - Dennis' Custom Anura with Alfine Mid-drive

Winter Store Hours: Mon-Fri 10-5 (MST), Sat 10-4 , Closed Sun. | 40 S Main St., Payson, UT 84651
Call or email anytime for quick response: Toll Free: 866-446-2065 | Local: 801-804-5810 | trikes@utahtrikes.com

INTRODUCING THE CATRIKE COLOR FEST PROMOTION - SAVE UP TO $250 ON A CATRIKE!

Sitemap

Dennis' Custom Anura with Alfine Mid-drive

Get your own Greenspeed Anura SL
When Dennis called me he asked if I could make him a custom Anura with a bottom gear of 9 Gear Inches and no derailleur. Always up for the challenge, I said "you betcha!" We eliminated the derailleur by mounting a Shimano Alfine as the mid-drive. We got the gear range by using a Schlumpf High Speed Drive (27T).

Mid Drive
Mounting the Alfine as a mid-drive presented a few issues because it had to be placed above the rear differential. We wanted our mount to be able to slide on the main frame tube so the chain tension could be easily adjusted. With the transmission hanging at an ange over the differential we needed a torque arm to prevent the mount from flexing. The result was a rock solid mount.

Main Drive Chain
To make it easiest to mount the primary drive chain, we used the disc brake mounts on both the Alfine and the differential to mount our sprockets.

Shimano Alfine Transmission
The heart of our new drivetrain is the Alfine transmission. Our new favorite! This transmission gives us eight super smooth gears. The Alfine is Shimano's most efficient hub transmission.

Revo Shifter
We pair the Alfine with the Nexus Revo Shifter. It's a grip shifter that is very easy to turn with a good solid click for each gear.

Schlumpf High Speed Drive
To get the gearing we needed we went with the Schlumpf High Speed Drive. In low gear it gives us a 27T chainring. In overdrive it gives you the equivalent of a 68T chainring. Combined with the Alfine in the rear it gives us a total gear range of 9-69 gear inches.

Chainline
A modified chainline was needed to get the power from the Schlumpf to the Alfine. We moved the power idler to the rear seat bolt position. For the return side we are using an idler built into our mid-drive mount and some modified chaintube routing.

Green Greenspeed
The color just seemed right for the Greenspeed Anura. Anura is a species of frog which makes it even more appropriate.

Differential
One of the key features of the Anura is its geared differential. This works just like the differential in your car. It allows both wheels to be driven even when you take turns.

Fenders
The Anura fender system is slick. The fender stay clamps on to the rear axle frame and then the fender slides on the top. The fender is secured with a clamp.

With the seat off, you can get a clear shot of the chainline.

You can see the return idler mounted to the mount. This idler acts as the primary chain guide for the drive sprocket. Mounting the idler here also increases the wrap on the sprocket to lessen the need for high chain tension.

Clearance
Not the best shot for what I wanted to show, but with no derailleur hanging below the trike we now have lots of clearance.

Share your comments below:
Ashley, great pictures!!!, I should have delivery of the trike Friday. I'll stay in touch. Thanks for all of your hard work.

Dennis
Posted by Anonymous
03/04/2009 02:50:22 AM

For a Delta she looks Sweet, Great work, keep it up Guys.
Posted by ajelliottjr
03/04/2009 08:04:05 AM

For a delta?!? This Anura is one bad mutha!
Posted by Ashley

Congratulations on the new trike Dennis!
The Anura looks great Ashley. Utah Trikes has come a long way since I first became aware of the company. No longer just a dealer but an innovator of design ideas. Hats off to you guys and keep pushing the envelope!
Posted by mi7d1 --> Portland, Oregon
03/08/2009 08:30:34 AM

Very cool.
Posted by Karl
03/14/2009 08:56:36 PM

wow this is just what i've been wanting! What was the damage?

Posted by bob
03/23/2009 07:14:26 AM

We are considering making this a standard option, but in the meantime it is a custom deal, so give us a call or email us and we can go over the options and pricing.
Posted by Ashley

The only thing better than riding this is looking at it. I'm traveling by car and it will be some time before I can get to ride again.
Posted by Dennis
04/09/2009 05:22:41 PM

So how did he like it...hows it riding for him???
Posted by deRoland
06/27/2009 08:16:52 AM

All reports have been positive. We have several customers with this same configuration and everyone loves it.
Posted by Ashley

Anura owners with Alfine mid drive anyone interested in exchanging ideas? We could start here and perhaps move if there was sufficient conversation.
Posted by Dennis
08/14/2009 09:55:46 AM

Let's hear it guys! I know there are at least a dozen of you out there.
Posted by Ashley

I'll start the discussion with a question. What do you think about replacing the chain with a belt? I notice that Trek has that option.
Posted by Dennis
08/16/2009 01:23:49 PM

Comments:

Nickname:

E-mail (not published):

All comments are moderated by Utah Trikes staff. We reserve the right to remove or edit any comment that we deem to be inappropriate. After you add your comment it will not immediately appear until a moderator has read it.