We first caught sight of the Ibis Tranny 29 as it was being ridden to victory by Jefe Branham in the grueling Tour Divide this year. Today, Ibis released the full details as the bike is making it’s public debut.
The sleek new frame comes in at a weight of 3.08 lbs but also boasts a plethora of unique features listed below:
- 3.08 lb Carbon monocoque frame
- Designed to work with 100mm suspension forks at 44mm rake
- Also designed to work with 120 mm forks with 51mm rake
- Geared or Singlespeed compatible
- Gates Carbon Belt Drive compatible
- Internal routing for dropper posts
- Clean, versatile multi-option internal cable routing
- Tapered head tube (suitable for various Cane Creeks & Chris King InSet 3)
- BB92/Press GXP style integrated BB
- 142mm Maxle rear axle
- 160mm carbon fiber post mount rear brake mounts
- Headset: IS ZS44/28.6 | EC49/40
- BB height w/ 2.25″ tires: 302mm (11.9”)
- Geometry measured with 500.8mm axle to crown fork
The Tranny is all about versatility. It can be set up with a standard fully geared drivetrain, or if you choose to it can be set up as a single speed. You can even run the Gates Carbon belt drive and keep the bike extra smooth and quiet.
Chain tension is applied and adjusted via the “Slot Machine” – an adjustable box section tucked into the bottom bracket yoke.
SLOT MACHINE
The slot machine (pictured above) is the sliding box section behind the bottom bracket that allows us to convert this bike to a single speed. By changing the length of the chainstay, you can tension the chain (or belt) without cumbersome adjustable dropouts or heavier eccentric bottom bracket.
Take a close peek at the section behind the bottom bracket. There’s some hidden equipment down there we call the “Slot Machine”. It’s not really a machine, but it does have a slot that makes it adjustable. That allows us to lengthen the chainstays, so you can tension the chain (or belt), converting the Tranny into a bona fide single speed. Single speeds don’t have a derailleur, which is normally how a chain is tensioned. The slot machine takes care of that tensioning in a simple yet effective way. It’s lighter than an eccentric bottom bracket, cleaner than a chain tensioner, and unlike sliding dropouts, can be adjusted with one bolt.
As an added bonus, that same box of magic along with the gorgeous bit of teardrop hardware at the top of the seatstays allows you to take the whole rear end off of the bike. Two bolts and it’s in two pieces. Why would you want to do that? That makes the bike easier to travel with, and if you’re really nice to the people at the ticket counter, it just might be possible to fly with this bike, er, luggage, and not pay the exorbitant fees the airlines like to charge us to carry our recreational necessities. We’re not saying that you can always get away with this, but we’ve done it in the past and we’ll certainly try it again.
One other thing, the slot machine now has a nice little molded dust seal to keep dirt out.
CABLE PORTS
Another example of elegant simplicity and versatility is shown in the cable ports. There are many possible ways to route your cables on the Tranny 29.
For dropper posts, there’s internal routing that can be fed through the top tube if you’re not using a front derailleur, or through the down tube if you are. The front derailleur housing can be setup with either full housing or interrupted, minimizing the rattle potential. The rear derailleur is routed with full housing through frame. It’s very easy to route because the slot machine opens up, allowing you to route it both over the bottom bracket and back into the chain stays.
Additionally, all the ports come off leaving a larger hole to aid in routing.
There are three different ports to choose from. You can use the thru hole routing for full housing or one with an integrated cable stop for bare cable. We also have blank ports if you’re not running any cables. The internal post and rear derailleur have to be run with full housing, the TT can be interrupted.
The specs are as follows below:
For more information – Click Here
