Originally Posted by
idiq
I don't think that the road bars will wholly get what you're looking for. For instance, the plain ones will have cable guides. Also, you'll need something to deburr the carbon after you saw it. Plus you're paying a lot of money to hack bars for 3-degrees, not worth IMO. I'd still recommend finding 31.8 carbon bars and using those with the Thomson X2 stem. The bars will taper in enough where you won't have much to worry about in the way of scratching (although what grips you use will matter, or tape) even if you marginally loosen the bolts.
The problem is that while it's easy to see that an unswept bar will provide the most margin for error, I'm not entirely sure how much that margin will be compromised by a 3 degree sweep.
3 degrees amounts to a 5% change in rise over run on average. I'm not sure how wide the face plate is on the Thomson, but assuming it's around 2 inches, in the worst case scenario (all the sweep from a single kink) I'll need 2.5mm of extra play in the loosened stem clamp just for the sweep which doesn't leave much room for tape on even a 31.8/22.2 tapered bar. This is, of course, the worst case scenario, but I like to have a margin of safety when dropping hundreds on parts sight unseen.
It depends on where exactly the bar bends and how much clearance I'll be able to get with a QR bolt in the face plate without compromising consistent clamping force.
Originally Posted by
rudetay
I think you're missing a vital point here. If you have the Thomson stem you can just completely remove the front plate and the sweep/size/grip whatever about the bar is completely irrelevant. That way you can make choices based on fit and comfort, not on some strange limiting idea that won't end up saving time at all. You won't even need a carbon bar with this set-up because you could just wrap up the entire bar. Or, you could just use gloves and the warmth element won't matter.
In response to the QR again, I can assure you that the bike did not come designed with QRs intended to be used with carbon parts. It might work fine for you so far, but when it does fail it will either be a crack that will make your expensive carbon bars unsafe to use, or it will just snap. It may never happen, but when there is a very easy way to do things as it is intended, why not follow the instructions? I can't imagine the difference between screwing two bolts and doing a QR is more than a minute or two. I can't even imagine how you would get a QR to work with a Thomson stem, let alone any other modern oversized stem. If you have a method, I'd love to see it.
You proposal of cutting down road bars is equally as weird, you're going to have a very narrow bar that will likely have cable grooves and other "features" and even after that will likely not match your perfectly straight requirement. A 3 degree sweep bar cut to the width you'd get from road bars would have such a small sweep it wouldn't even be noticeable.
Just because you have devised an overcomplicated and convoluted solution to a very easy problem doesn't mean you need to continue making it difficult when easier solutions are presented to you.
But, you mention it uses a quill stem...so will any of this even be possible? You'll end up running a quill extender to a quill to threadless adaptor, to a threadless stem, to carbon bars? And, finally with a QR on that? Seems like if weight is a concern there's lots of other areas you could drop it.
The "quill stem" is really a "quill stem riser"; that is a straight 1" tube (for 1-1/8" steerer) with expander wedge at the bottom. It's basically like a quill to threadless adapter except it doesn't taper. The expander bolt is also QR.
A threadless stem is attached to this riser which is attached to a short (maybe 6"?) 25.4mm diameter bar. This bar has no taper, a 22.2mm internal diameter, and a QR collar on each end into which two additional 22.2mm bars are inserted (one on each side) with grips, levers, etc attached. To "fold" the handlebars, the left and right QR clamps are opened and the two 22.2 bars are extracted, leaving just the middle 25.4mm bar and the QR collars.
So while what I'm proposing may sound overcomplicated or convoluted it is still far simpler, easier, and more standard than the stock setup. The main thing enabling the simplification is that I run only a front brake and am willing to compromise on the grips, allowing the single middle stem clamp to perform the same function as the two QR collars and eliminating the three-piece handlebar entirely.
The total time to fold the bike is well under 30 seconds including the handlbars and, in fact, most times I don't even fold the bars at all because it takes too long. So switching to something that would take a minute and incurs the risk of losing small parts (like the face plate or bolts) is unacceptable, although I would be willing to just loosen a single bolt with an allen key if I can't make a QR setup work.
I don't want to discuss what components are or are not designed for because I have a history of using components as they are not designed with great success and for someone reason that makes people really angry and gets my threads locked, which destroys my chances of picking the brains of forum members.
I'm also hesitant to post that my end goal is actually "folding" because I don't want to be told to ask in the folding forum when 0 sweep bars are, for some reason, marketed as fixie bars.
Originally Posted by
axcxnj
you could always just buy some carbon fiber tubing if having 0 sweep is so important
There's two reasons why I can't use untapered tubing like that:
1. I'm running a front brake so the bar needs to taper down because the diameter a handlebar needs at the stem clamp is too wide for any kind of lever.
2. I'd like to use at least a thin layer of tape for wet grip, so I also need some taper for it to slide through the stem clamp.