Tor Zenith

Introducing the Tor Zenith!

On show for the first time at the Handmade Bicycle Show Australia in Melbourne on May 7-9.  

A Trail Bike

 The design of the Zenith was inspired by the lengthy group chat discussion preceding our regular Wednesday night group ride. Where are we riding? How long are we heading out for? What bike should I ride? These rides can be anything from an XC loop , a climb up to a summit for a view, DH laps or sometimes all of it! We think this bike allows you to ignore the pre ride banter and pick up the same bike week in, week out and have a blast!       

The Basics (custom show bike)

29″ wheels front and back

130mm rear travel with a 140mm fork

66° head angle

75.5° seat angle

175mm dropper post

Handmade steel frame using a mix of Reynolds and Columbus tubing

Custom Large Sizing

Suspension Design

Yep, it’s a single pivot. Simple, reliable and easy to maintain. At the beginning we had some goals in terms of kinematics and were prepared to try different suspension platforms but were able to achieve our goals with the humble single pivot. There are no standards when reporting MTB suspension kinematics so we’ve kept terminology and methods simple and inline with what we believe is industry standard. 

 

With 0.9% progression at an average of 2.2 the leverage ratio is very linear. This provides a predictable feel throughout the range of travel and allows for a straightforward tune. Volume spacers in the Fox DPX2 shock can provide a range progression and firm up the bottom end.   

 

 

Contrary to internet stereotypes, a single pivot can pedal really well! With a 32T front chainring and 46T rear cog the anti squat is 110% at 0mm of travel, 104% at sag (30%) and finishes at about 87%. Keeping that number above 100% through the pedaling zone means you always have support from the bike. Keeping anti squat close to 100% means suspension isn’t compromised when it gets chunky and won’t stiffen up and skip around. On long flat climbs the pedal platform switch is useful and will ramp up compression and help increase efficiency.

 

Our goal with anti rise was to keep the number around 100% through the range of travel. At 0mm travel the figure is at 110% and at bottom out it is just below 90%. At mid travel anti rise hovers around 100% so under braking there is very little pitching or diving caused by braking and weight transfer.

 

Pedal Kick Back is a pretty polarising topic and single pivot suspension systems can often be criticised for having high levels because of the elevated pivot location on older designs. Modern single pivot designs have much lower pivots and low levels of kick back. We’ve chosen a 32T/19T chain combination which shows about 8.5° of kick back at full travel. It’s often argued that pedal kick back is irrelevant and isn’t noticeable at low levels which we think is the case with our design.  

The Frame

Made from a selection of Columbus Zona, Reynolds 853 tubing and 1/8″ 4130 plate, this frame displays the compliance and grip that steel frames are known for. The pivot bush and hardware contact points are made from stainless steel to prevent corrosion and ensure ease of maintenance. A straight 44mm headtube, 73mm wide English threaded BB and full external hose and cable routing will keep bike mechanics happy and prioritise reliability. Dropper post routing is internal to the Ø31.6mm seat tube and exits neatly on to the downtube. The suspension and geometry is designed around the Fox Float DPX2 shock and Fox 34, 140mm forks. Rear post mount brakes with  8” rotor compatibility, 29” x 2.5” tyre capacity and boost hub spacing front and back.

Availability and Customisation

The Zenith will be offered as a tig welded frame in 4 standard sizes with a powdercoat finish. Sizing and geometry charts will be available soon. Custom builds will also be offered as a premium product with options a such as fillet brazed construction, custom sizing, custom geometry, varied frame finishes and customised componentry. All frames are built to order in our workshop in Beechworth, Victoria.

Pricing

Framesets (frame and shock) will be available for $5800inc GST. Current lead times are at approximately 3 months. Complete bikes well also be on offer so please get in touch to discuss options.