Tuesday, December 1, 2015

Yeti Tree Frog (S/N 2) trials bike

I finished this bike some time ago and just haven't had a chance to post up the finished photos. This particular Yeti Tree Frog was the 2nd production (consumer) version of the rare trials bike from the fabled mountain bike manufacturer. While the total production numbers for both team and consumer bikes are not know, the number 10 is commonly thrown around by ex-Yeti folks.

I've had the fortune of working on two of these bikes and wanted to take the opportunity to not just showcase this bike but also to bring up a couple differences between this and the one team bike I worked on a little while back.

The basic look of this Tree Frog is similar to the team bike. One of the main differences is the oval top tube borrowed from a production FRO compared to the round top tube on the team bike.

Custom painted Bullseye Tandem hubs with with 48 spokes make for some very strong wheels.

Custom Accutrax fork with U-brake mounts and a Campagnolo Euclid brake. The pulley system adds extra leverage to the brake system, but is difficult to setup in the confined space.

Custom Yeti stem with a removal faceplate enabled the use of riser bars.

Like most Tree Frogs and trials bikes in general this one uses a U-brake in the rear with the custom Yeti cable hanger. For whatever odd reason the team frame was actually setup for cantilever brakes.

The spacing on this rear hub is the standard MTB 135. Perhaps this was done to accommodate the Bullseye tandem hubs without any customization. By comparison the team frame had 115mm rear spacing using a custom built rear hub.

The team bike has dual gussets reinforcing the chainstay to the bottom bracket shell and a much wider loop section (there was a spacer welded in the middle) to provide more clearance for the 2.5" rear tire. This combined with a narrower rear hub eliminated the bend in the stays and created a more compact and maybe stronger frame

The oval top tube on this bike is quote striking in contrast to the subtle round top tube on the team bike.

The 166mm Bullseye cranks were only of the few upgrades I made. According to the original owner the bike actually came with Bullseye cranks, but the bearings got sloppy and he changed over to Monty trials cranks. 

Another view of the very cool Bullseye tandem rear hubs. I really feel like the wheels on this Tree Frog set is aside among other trials bikes. Using a tandem hubs is a really clever way of making incredibly strong wheels, which is key for this type of a bike.

All in all this was a very cool project and significantly easier to complete than the highly customized team frame. I really wish I had any sort of trials skills, it seems like a such a shame to have had these bikes here and be unable to do anything more than just hop around my back yard with them.