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This week we’re joined by Race Face, RideFarr, Ritchey Logic, Hope Tech and Fasst Co to answer your questions on carbon handlebar technology. Do you need to replace your carbon bar every time you crash (we sure hope not)? Is there a minimum width? What level of vibration damping does carbon offer over an aluminium bar? These question and more are answered by the following contributors:
How much vibration damping does a carbon bar provide over its aluminum counterpart?
Easton Cycling / Race Face: This depends a large amount on the design of the bar, and the intended purpose. While carbon handlebars can be more readily designed with vibration damping thanks to the nature of carbon fiber layups, shape, wall thickness, etc., it would depend on what layup and design was implemented in the bar.
A simple carbon fiber reinforced plastic bar would not inherently provide more damping than an aluminum bar, so check into the bar design. For Race Face and Easton Cycling, different product offerings provide differing levels of damping dependent on use.
Farr: There are a lot of variables to consider when asking this. Tube profiles, types of alloy as well as carbon lay-ups etc all can have a varied result. Generally speaking, carbon would offer improved damping (hence the attraction to use the material) whilst also allowing a lower overall weight. But again, depends on the carbon process and how exactly the material has been laid up.
Fasst Co: A composite bar will minimize vibration, however some will do this better than others based on wall thickness and composite layup, etc.
Ritchey Logic: Carbon provides increased damping over alloy, however we do not have a quantifiable number for this. We do static and dynamic testing, however we do not have a test which actually measures damping.
Hope Technology: If tuned correctly, a carbon fibre handlebar will provide more vibration damping than its aluminium equivalent. It is however very difficult to quantify this as fibre orientation, reinforcement (fibre) selection and matrix (resin) selection all play a part in the final laminated part. This is the beauty of composites. If done correctly, a component can be tuned for specific characteristics weather it’s stronger/stiffer or tougher/more compliant.
Do carbon mountain bike handlebars have a minimum width? I have very narrow shoulders and like to run my mountain bike bars no wider than 700mm. Also, if I cut the bar myself, does it invalidate the warranty?
Easton Cycling / Race Face: For Race Face carbon handlebars, we provide a specific cutting area that the bar is rated to, with convenient cutting guidelines. If you stay within the guidelines, your bar remains under warranty.
Cutting bars shorter than these recommended widths will invalidate your warranty, and would be dangerous as it changes the location of clamps for controls and grips to areas of the bar that were not designed for clamping. This would also result in non-optimal ride characteristics.
Farr: Our Carbon Endurance MTB handlebar is already quite narrow at 720mm. The industry “standard” is 180mm for the 22.2mm area, to allow for grips/brakes/shifters etc.
Our bar allows for 193mm in that area, so you could cut them down to 694mm if you needed the full 180mm. Grips at 130mm + Shifter/Brake at 40mm max would give you another 20mm to play with. So, down to 674mm? Given that you are decreasing the leverage on the bar, it should not be a problem to go even shorter… the bar actually becomes stronger.
Fasst Co: In our bars’ configuration we do not have a minimum width but trimming the bar will give it a stiffer ride and limit room for control mounting. Fortunately, with our technology, you can tune the bar to your preferences no matter the width. Trimming the bar does not void our craftsmanship or damage warranties, but would negate it from our 30 day money back guarantee.
Ritchey Logic: There is no minimum width. The min width will be sufficient length to install controls as needed on the 22.2mm round section of the bar. The length of this area should be shown in the sales drawings. All CF bars should now be without inserts and include cut marks. Note: the bars should be properly cut down and cutting voids warranty.
Hope Technology: Dependent on the manufacturer, most handlebars are to be run at specific minimum widths. This is usually designed into the shape of the handlebar depending on the discipline/characteristics required. The majority of handlebars have cutter guide markers on the ends for reducing the widths.
Cutting the bars yourself does not invalidate the warranty, however it is recommended that it should be done by a competent mechanic. If cut incorrectly this could cause delamination which would invalidate the warranty. We do our best to help prevent this being a problem by providing cut markers on the ends of the bar, increasing the wall sections on the ends and using a woven fabric to avoid splintering.
Do I need to replace carbon handlebars every time I crash?
Easton Cycling / Race Face: It’s important to take impacts and crashes seriously – they can result in damage to carbon composite products that may be difficult to see. Continued use of a damaged product may lead to product failure, serious injury, or death.
We recommend you stop riding the bar immediately and have a service professional with a local Race Face / Easton Cycling bike shop or retailer check for damage to the bar. Checking for evidence of delamination, or broken fibers, can help you determine if the bar suffered during impact.
Bending or impacts can cause delamination in the fiber layers, and cuts, scoring and abrasion can break fibers. If you have questions, reach out to our service centers – it’s always important to play it safe with the control points of your bike.
Farr: It is essential to check the surface for any cracks. That is the first tell-tale sign of damage and then of course you should replace it immediately.
You can also apply pressure on the bar to see if there is any deformation. You can typically hear a cracking noise upon applying the pressure if the bar has indeed failed or cracked.
Fasst Co: No, but at the very least you need to inspect the bar for any gouges, scratches, cracks, or abnormalities of any sort. Most carbon bars are strong enough to withstand the impact of a crash but you can never control how or what the bike hits in the event of a crash. It’s good practice to make inspecting any composite component part of your routine maintenance.
Ritchey Logic: I would advise inspecting bars after every crash, and any evidence of marring of the carbon should warrant a replacement.
Hope Technology: No. It is however recommended that you look for any tell tale signs of delamination or damage after any crashes.
Is it possible to overload a carbon bar with too many controls? With the stem, lock-on grips, brakes, shifters, Garmin mount and eBike display unit, I’m up to nine clamps. Do manufacturers’ tests take these things into account?
Easton Cycling / Race Face: The weight of controls alone will not overload a bar, but it is possible to compromise the strength of a carbon fiber or even an aluminum bar by installing controls incorrectly. Certain areas of the bar are built for clamping – round areas where controls and grips are installed are designed to handle manufacturer specified torque ratings for the levers, shifter and other accessories designed for bikes.
And, the round area at the stem has been designed to take the load associated with stems. However, areas that are outside this – riser areas on MTB bars, the aero section of a road bar, places that cable routing has been introduced through shaping or holes – are not designed for clamping as they have unique profiles and can’t bear the load cross the full circumference.
For items like E-Bikes, there are bars that are rated for the additional load required, and it is important to use E-Bike rated components. Finally, it is critical to ensure that any accessories are torqued to manufacturer specifications and in those specific areas of the handlebar. And yes, our handlebars are designed and tested with consideration of controls.
Farr: The control area – that 180mm area I mentioned earlier – is tested to roughly 30% above the torque requirements of the related items like lock-on grips/brakes/shifters etc. It is always a good idea to use a torque wrench to ensure correct torque settings are being applied.
With regards to the stem area, both our MTB and Gravel bars are reinforced to allow fitment of aero bars (like our Aero Bolt-Ons or more traditional Aerobar setups) in that area.
Fasst Co: In development we tested the effects of clamps and torques. With a Flexx Handlebar the clamps are distributed through three components; two handles and one center tube thus, isolating the clamp load. The most critical issue always comes down to properly torquing the controls, no matter the number of clamps.
Ritchey Logic: As long as torque specs are adhered to, this should not be an issue. We conduct static and dynamic testing that far exceed ISO requirements and although we do not specifically test with additional devices, we do test with significantly higher static and dynamic loads.
Hope Technology: Your limiting factor with any handlebar is whether there is enough room to mount all your controls. This is one of the reasons manufacturers are trying to integrate more controls together. Lab testing on handlebars only requires a stem to be mounted to comply to industry standards.
All our handlebars are real world tested out in the field for many months (sometimes years) using all types of disciplines. Much of this proves out any knock-on effects controls have on the product.
Manufacturers should take these abundance of controls into account as space needs to be provided for them at the initial design stage. There is also a certain amount of clamping force to account for on each individual control which should be taken into consideration for the laminate design.
I’ve over-torqued the brake clamp on my carbon handlebar. On the clamp area, the finish of the bar looks different to the finish elsewhere. It’s gone shiny. Have I written the bar off or will it still be fine to ride?
Easton Cycling / Race Face: Unfortunately, this isn’t a simple answer as it depends on how over-torqued as well as the clamp design of the control. Depending on the clamp design and the extent to which it has been over-torqued, there is a range of possible consequences.
They may have only altered the cosmetic finish of the bar and it would be structurally unaffected and OK to continue using. However, they may have caused visible or invisible (internal) damage to the carbon fiber structure resulting in a bar that is not safe to ride and should be replaced.
Shiny does not necessarily mean the bar is damaged as this can be a change to the cosmetic finish and this can often happen with standard torque spec, but it would still be best to contact a service center or shop.
Farr: Assuming you are referring to a Matte Carbon finish on the Carbon product, the shiny finish is just the removal of the Matte Clearcoat that was applied to create the finish. It is non structural and purely cosmetic. The bar is still fine to use.
Fasst Co: The most important thing to keep in mind with a carbon bar is not to over tighten the controls. Over tightening the controls, whether the bar is crushed or not can create a stress riser that will likely become a failure point.
The Flexx Handlebar wall thickness is thicker than industry standards as we don’t want any movement out of the handles. We want all that energy going to the pivot pin of the Flexx Bar. With that said, it takes a serious effort to over tighten our controls and crush the carbon but it can be done. We ship our composite bars with a sticker on the handles indicating the max torque spec for the handles.
Ritchey Logic: If a bar has been over torqued and there is a noticeable variance to the finish, I would immediately discontinue use and reach out to the dealer/manufacturer for comment.
Hope Technology: Any product should have a certain factor of safety built into it. Slightly over torquing the brake clamp shouldn’t have any detrimental effect on the bar, but it’s worth checking to see if any damage has been caused. A shiny surface underneath the controls does not mean the bar has been written off.
This is very common on most carbon handlebars which have a Matt lacquered finish. Lacquer is applied to most carbon fibre products to protect them from UV degradation which, long term, could cause a failure. Matt lacquer is applied as a very fine mist coat and has a very rough surface at a microscopic level.
By clamping onto that rough surface you are leveling out the peaks and troughs creating a smoother surface more like you would find on a Gloss lacquered component. This does not have any significant effect on the mechanical structure on the handlebar.
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