HyperStem

 

Bolt tightening

The special M4 bolts of HyperStem at 2Nm pull about the same of a regular M6 bolt at 4Nm.
Note also that we recommend those mild tightening torque values in order to protect the steer tube and handlebar surfaces that are often very weak due to the fully absence of transversal fibers.
HyperStem bolts can withstand over 5Nm but do never tighten them that much for a number of good reasons.
Degrease well all contact surfaces, then lube only HyperStem bolts and tighten as for manual sequence.

 

Bar & fork combo

HyperStem stiffness is excellent and bench measurements show it well.
In the last 12 years it has been used by several world team athletes and by MTB world-champion too, and as many athletes of several other racing categories they have regularly purchased every Extralite part.
Additionally HyperStem is one of the most "carbon friendly" stem on the market since it features rounded edges at every joint.

However note that handlebar (especially its clamp area) and fork tube materials play a major rule on the stiffness and integrity of the whole combo. In-facts the construction of composite handlebar and fork tubes can be more or less reactive under clamping forces.
The reactivity under clamping forces is mainly supported by the presence of transversal fibers and unfortunately these are often fully absent on the majority of industrial products, including famous ones.
This will be even more important in case of lightweight handlebars.
When looking for weight reduction we can only recommend these Schmolke, Darimo for a proper fit and durability, very few hi-end lightweight products are made that properly and with the correct positioning of cross fibers at the clamp area.

 

Bar rotation

Handlebar type of construction and the conditions of contact-surfaces are the primary reasons of unwanted rotation when setting a lightweight stem-handlebar combo.

How to solve it:
- De-grease well bar and stem contact surfaces and precisely follow the tightening procedure of HyperStem manual.
- Do not use "grip pastes", under bench tests these proved to be totally useless, we do not recommend them.
- Remind to re-check clamp bolt torque after few test rides, as manual explains, that handlebar paint and surface may have shrunk under clamp pressure.

Never get tempted to over-torque the front clamp bolts
- That may easily ding and damage a weak handlebar surface.
- HyperStem can handle 50% overtorquing that may be applied to stronger alloy handlebars.
- When the over-torqueing get truly exaggerated it could bend even the HyperStem clamps and bolts.

HyperStem proved to work well for years with all properly made super-light hi-end handlebars.
Lightweight handlebar combos
- We warmly recommend to use only bars that feature crossed fibers at least at their central section (see Schmolke, Darimo and Extralite as best examples).
- That because the most common (and cheaper construction) methods employ only UD fibers and those react very poorly under clamping forces.
Those handlebars may work well only with conventional heavier stems.

 

100% made in Italy