Is anyone else having problems with clip-on’s by having to use adaptors to put them on 31.8 bars? Syntace offers an adaptor, but it adds nearly 1/2 inch to the height of the arm rests (not to mention having cracked carbon bars by trying to torque down the adaptor assembly).
I’m looking at Profile’s site and it says it has a Multi-Fit system, but it looks like there is only 1 part number, which leads me to believe there is an adaptor for one of the 2 sizes, not sure which one.
Profile’s clip on bars are made for 31.8 bars. Included are shims to allow them to fit on the standard 26.0 bars.
Hope that helps explain the Multi-Fit system. We sell a lot of their clip on bars and have been happy with how they aren’t specific to any one bar diameter.
The problem with 31.8 generally isn;t the total outside diameter, it is usually the taper from the 31.8 mm section to the normal handlebar diameter section. A bolt-on aerobar will not tighten adequately or safely on the tapered section.
In general, if aerobars are going to be used, I use 26.0 mm outside diameter cockpits for our customers. The variations in the construction and configuration of 31.8 bars generally mean they were not designed for use with bolt-on aerobars in mind.
Unfortunately, I don;t know a good solution to that problem. There may not be one. I don’t like shims, it is another place for a failure to start. I have seen and had them let go when nailing a bump on the aerobars. I had one let go on a pair of Profiles I was test riding for a customer in the parking lot yesterday. They came off and Visiontech went on.
I don’t know that there is a solution for 31.8 mm aerobar mounting on drop bars right now. If there is one, I would like to hear it. Whatever you do, don’t clamp to the taper- it is dangerous. That’s why with aerobars, it’s 26.0 drop bars for my customers.
Thanks Tom - that actually helps a lot. What you described is EXACTLY what happened. Trying to install Syntace C-2’s from an older Trek with 26.0 to a new Madone with 31.8. Couldn’t get them tight enough to stop slipping then all of a sudden - CRACK! I’m thinking aluminum 26.0 for the bars and carbon clip-on’s.
What would you recommend for a good 26.0? This is my girlfriend’s bike. I have Profile pursuit bars on my Aegis and have not seen a problem whatsoever.
I have 31.8 and use Carbon Strykes. It depends on how far inward you put the clamps toward the stem. A correctly placed clip on on a 31.8 however is going to be right on that slope you are talking about.
The way I deal with that is that I go ahead and put one 26mm shim on under the top oval right on the slope, even though I have 31.8.
Tom is right, though. I was told this over and over here not to buy 31.8 oversized bars if I intended to use clip on aero bars. I looked around at both Syntace C2s and Streamliner and PD Carbon Strykes and since they had the adaptors, I didn’t think it is a big deal. However, its the adaptors that give you the problem, its exactly what tom is saying about the “taper” or slope on the oversized bars. You can get a good grip on the 31.8 by moving the clip ons closer to the headset/stem, but I don’t like my aero bars that close together. On Ritchey WCS OS 31.8 for example, the best place for the clamps is right on the edge of the taper. So, i’ve got some part of the clamp on the OS and some on the 26 part of the tube. I therefore I’m forced to use the shim.
If you are weight bearing pretty good on the extensions and you hit a bumpty bump, there’s not enough tension to keep those bars from loosening with shims on a 31.8. You just have to to tighten every trip. And expect the worse.
Hmmm. When I checked back in on this thread I was hoping there would be some insight I hadn;t heard of. It is amazing how, in this industry, so many products are relleased and distributed before much though is given to whether or not they really work.
Wouldn;t you have thought that a few of the aerobar manufacturers who were making a 31.8 clamp diameter aerobar would have bought a bunch of popular brand drop bars and then tried to bolt their aerobars on them to see if they actually worked? Maybe they did and they know something I don’t- that was what I was hoping to see in this thread, but we haven’t had that yet…
Another plug for my favorite aerobar guys at FSA/Visiontech: The 31.8 clamp on FSA/Visiontech is so narrow it will butt right up against the stem and occupy very little clamping space. That is a nice design. Also, there is no shim stuff going on with regular FSA/Visiontech aerobars (the shorties use shims) They make different clmap sizes for 26.0 and for 31.8- no shims. That is a huge commitment on their part since it doubles the amount of SKU’s the company has to produce and distributors have to stock.
What is the absolute word on using clip-on aero bars on carbon road bars. Not for extended use, just for the odd Triathlon race or TT - say 3 - 4 times a season for short triathlon races and TT’s. Assuming bar shape is round at the traditional point of contact.
It is said up and down that this is a no-no, but then the same people who are saying this are saying that the carbon road bars are bomb-proof and “stronger than aluminum”.
We should note that 31.8 bars can taper in (2) different areas. Some taper right out of the stem, others taper after an 1 inch or so…
The bars that taper out of the stem are pretty much a no-no to clip on bars, mostly due to clampable (did I think of a new word?) real estate. The bars which allow room for taper have basically been engineered to accomodate clip-ons.
Take for example Easton’s Pro Bar…“thumbs up” for Clip on aerobars (31.8 clamp). The trick would then be to find an aerobar with can have a narrow clamp, but allow for a wider elbow placement.