joshuadn11

Hi all,

i recently purchased one Control Tech Viento SC Ergonomic handlebar Ø:31.8mm and a TT Profile Design Legacy Aerobar.

The aerobar is compatible for 31.8mm but the thing is only my Control Tech handlebar's stem part is 31.8 and both part next to the stem part is much thinner than 31.8..

I even tried using the clip-on attachment to make my handlebar "thicker" so the aerobar will be fully attached/unmovable when i place my arms/elbow on it....

should i just use some handlebar tape and wrap it several times to make the handlebar "thicker" in order to create resistance for aerobar to stay in place?

sorry still new to the forum and all helps are greatly appreciated!! since i dont want to return the aerobar or replace my handlebar

Amazon.com : Control Tech Viento SC Ergonomic Bending Road Handlebar : Bike Handlebars : Sports & Outdoors (this is the handlebar i got and you'll see the "thin" part next to the design/logos)

https://www.amazon.com/Profile-Design...+design+legacy (this is the TT aerobar im referring to)

seedsbelize 

Since you don't want to ditch either of them, it seems shimming is your only option. Maybe use something that glues to the bars to reduce the possibility of slippage.

hueyhoolihan

i've only had success attaching aerobars that needed shimming was with an alloy handlebar and a couple of pieces of another handlebar that i had to cut lengthwise to fashion as shims. any kind of non-metal shim ended up being a waste of time.

BTW, there a few road bars that do not have a wider OD at the clamp than elsewhere on the bar. how far it extends beyond the actual clamp's width is not standard, AFAIK. i've had to clamp aerobars on RIGHT NEXT TO THE STEM CLAMP in order for the aerobars to be secure enough for riding. if i wanted or needed them further apart for some reason i had to use a shim. some come with shims for this purpose, i believe.

e_guevara

The 31.8 mm refers to the diameter of bar clamp section, not the entire handle bar. Some bars are marketed as "compatible with clip-on aero bars" that have a longer clamp section. The regular diameter of road bars (past the clamp area) varies from 23.9 mm to 26.0 mm depending on the manufacturer.

My Profile Design T1+ came with shims for 26.0 mm and 31.8 mm bars.

I wouldn't use handlebar tape to thicken up the bar. Even with an adhesive backing, it will just slip due to the torque of your arm placed on the aero bar. Further, handlebar tape deforms, changing the effective clamping diameter.

You could buy shims from Wheel Manufacturing or Problem Solvers for 25.4 mm/26.0 mm to 31.8 mm. Do note that are intended for shimming the stem clamping area. If your handlebar's diameter past the clamp area is smaller than 25.4 mm, you may need to use a DIY shim such as an aluminum can.

joshuadn11

yeah the shimming provided by Profile Design is just like a plastic clip....but it twists whenever i put my arm onto handlebar; seedsbelize: should i just use some glue like you suggested?

hueyhoolihan: i tried fitting my aerobar right next to the stamp clamp and it's only like 30-40% on the clamp....quite scary and hard to to do it

Thanks for alternative suggestion guys!! i guess ill give them a go and see how it goes.
(https://www.bikeforums.net/singlespee...ebar-shim.html) like that < i guess....sounds unsafe but seems like people have success w/ it

fietsbob

Know any Machinists? they can make the perfect thing, just for You.


you trying to fit it on a taper off the center bulge ?

or the 23,8 ish part for the rest of the handlebar ?
is it even round there?

e_guevara

The shim is for a 26.0 mm diameter bar. Measure your bar's diameter at the narrow section and see if it is 26.0 mm. If it is, then you probably aren't tightening the clamp on the aero bar enough. Use a torque wrench (if you have one) to tighten to spec.

If the bar's diameter is less than 26.0 mm, you have to use a shim.

Don't do it. The clamp is designed to spread the clamping force over a given area to provide a safe clamping pressure on the bar. Reducing that area increases the clamping pressure beyond what the bar can probably handle. The Viento is aluminum though, but I would still advise against it.

It works. It's not rocket science.

Not a good idea ...

hueyhoolihan

i hear ya. they didn't give you much room to work with on the clamping area of that handlebar, did they?

like i said, i've used shims to good effect. in fact, it's a Profile Jammer set of aerobar that i have.

they came with a set of plastic shims, i cut two, two inch, sections of old mtb bars and split them, as i mentioned before to fashion some shims and then used them together with the plastic shims that came with the bars. when mounted (not easy with two sets of shims, each set having two shims!!) they performed well on a tour, carrying a light load strapped to them like a front rack, in addition to my weight.

you might, and i do mean might, be able to do the same with an old road bar. good luck.

BTW, did you get a set of plastic shims with that bar? if not, it must have been a mistake. i don't see how it could be advertised to work with two different diameters without them, unless they have some other mechanism to reduce the diameter of the clamp.