Geometry question for the people who ride multiple types of bikes
What professional road racing team you riding for this year Jonsey?
@Wuffles Same question to you.
Plus...
Care to explain the hordes of disc brake spec'd roadbikes produced and sold by major manufacturers in the year BEFORE discs were finally allowed in the UCI handbook?
2. What? Why is it steeper?
Maybe they knew UCI will allow them.
Total seat-of-the-pants point of my part, but: compare roadie headtube angles now to those from 50 years ago. Older road-bikes are slacker, which was probably because the road conditions were crappier. However, as road conditions improved, it was possible to optimize geometry by steepening the angles for better power transfer and hard cornering performance.
Again, anecdotal, but I am pretty sure that my current Taiwanese crabon roadie is quite a bit steeper than my first roadie, which was a mid 80s steel Pullaghi or something like that. My current -steeper- ride handles much better for the type of stuff it is meant to do.
EDIT: Looking at images on the google it appears that older roadies just had more rake. <shrug>
Motorsports analogy (of questionable validity): just because 30 inches of wheel travel works great in a Trophy Truck, doesn't mean you need it on an F-1 rig.
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then ban them again... then allow them again... then...
Or bag the racing crap and just ride your bike...
Not sure if any of you are aware. but plenty production road racing frames use different head and seat angles throughout the frame sizing. not just the longer toptubes, seat tubes and head tubes that you generally find in mtb frame design.
Dude. I'm well aware of how many folk buy roadbikes with zero intention of ever racing them. nevermind UCI ranked racing. Vs number of folk who will actually buy a racing licence.
How is steeper head angle better for cornering? They do it to increase the weight over the front wheel? I didn't think that was a problem with the position that roadies use and I don't see any other reason to do so. Faster steering at 90kph seems like a bad idea. I just don't see the benefits of not going slacker.
Yeah I know it. I just don't understand the reasoning behind super steep head angles when you already have a ton of weight over the front wheel and the gradients both up and down are smaller than in XC racing so you don't really have to worry about front wheel getting jiggly
eh?
What makes you think there's a ton of weight over the front wheel?
What makes you think there's a ton of weight over the front wheel?
Er.. you really should re-think that statement.
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Yeah a road bike with a 73° STA and short stays. A lot of weight is in the rear. With reach getting longer this has lighted the front wheel.
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I never bothered to think about WHY this is the case, but my experience indicates that current geometry is better for road riding. Racing crits on modern road bike geometry feels right. It's comfortable, it's efficient and it's predictable. I can -though don't often- push the speed in corners till the tires chatter and I know that my tires are gonna be equally weighted without having to move my COG forward. On my trail bike I change my COG constantly depending on where I want traction bias. The thought of racing a crit on my touring bike gives me visions of understeer in hard corners and imprecise steering in the pack. In order to compensate for that, I'd have to move my COG forward on the fly, which would completely fack up my pedaling efficiency. That said racing cyclocross on my slacker touring bike would be doable and possibly an advantage for rougher courses. I dunno what else to tell you.
Fwiw, I don't think anyone is saying to make the head angle steeper than it is now.
this thread makes my head hurt.
Clearly a result of your malfunctioning geometry.
The bars are really low.
As for the bars getting jiggly - seriously? I've done a few famous climbs from Euro Tours and they don't have those super steep sections that sometimes popup on XC racing tracks.
Why are you talking about pedaling efficency when we are talking about downhill cornering? I get that modern road bikes feel comfortable I just don't think that's a really strong argument since for many people old steep as shit downhill bikes also felt comfortable and new ones were "too slack". Not saying we should go slacker on road bikes. Just trying to understand.
@Cerberus75 isn't this offset by the low bars? At least to some degree?
Most of the extended "technical" discussions in the DH forum make my head hurt.
Gary no reason to get so emotional. I know what is road bike wobble. Yeah I have seen roadies torso but I don't know the exact weight distribution on road bikes. As someone else has mentioned - short cs + long reach means the front has relatively little weight on it and since roads aren't super steep slack head angle may be a problem all other things being constant.
Still one thing makes me wonder (I know it's annoying for you but then again - what isn't?) why are short stays popular in road bikes?
Also what's wrong with me being curious about road bikes? Is it better we only post pics of our bikes and argue who hates the bike industry more?
@Cerberus75 isn't this offset by the low bars? At least to some degree?[/QUOTE]
Not really with a slack STA your weigh is pretty planted between the rear axle and Bottom bracket. Even in the hoods I dont have my weight in them unless standing. I can remove a hand or both while seated. And I'm more top heavy than most guys on a bike.
On my MTB the STA is 77° this changes a lot for me. During long peddly rides my hands would go numb (I do have nerve damage from powerlifting and martial arts so this happens easily) didn't stop till I slammed my seat back. So I'm going to get a set back post. So I Can still slide it forward on days where I'm only in the saddle while climbing.
Not really with a slack STA your weigh is pretty planted between the rear axle and Bottom bracket. Even in the hoods I dont have my weight in them unless standing. I can remove a hand or both while seated. And I'm more top heavy than most guys on a bike.
On my MTB the STA is 77° this changes a lot for me. During long peddly rides my hands would go numb (I do have nerve damage from powerlifting and martial arts so this happens easily) didn't stop till I slammed my seat back. So I'm going to get a set back post. So I Can still slide it forward on days where I'm only in the saddle while climbing.
Team Basic Economic Logic. Our kit is covered in dolla' bills. Whose yours?
As far as disc brakes go, the UCI flat out told everyone they were going to allow discs on the road at some point in the future, and since they already took over CX the writing was on the wall for all to see. Team Basic Economic Logic strikes again.
So that they’re easier to manual, duh
(Unless you’re Gary, for whom all bikes manual equally well.)
I don't consider them especially short. (and you can but roadbikes with longer chainstys). look at the whole bike's geometry. The entire bike is short. most meduims are sub 1000mm wheelbase.
There's nothing wrong with being curious. But go and ride one. infact, a few (probably for a few years) before thinking you've worked out how to improve the handling of them by simply stealing ideas from downhill mountainbiking and throwing them randomly at the design process.
Now... now.. .@toshi... That's not really what I said and you know it.
I'm not emotional. Unless you find a *sigh* a highly emotional state.
Ps. This is the exact opposite of "make it stop!"
for the amount of resources it takes to make a high end road race frame these days - engineering resources, FEA, prototyping, wind tunnel time, etc - do you honestly think it makes financial sense for a bike company to make a road race bike UCI compliant and then not release it to the public for sale? seriously, where do you honestly thing that R&D money is gonna come from? e-bikes? how do you expect them to recoup those costs?
first that by eliminating the need for braking surfaces on the rims, it opens up huge possibilities in terms of aerodynamics and lightweighting since rims won't have to withstand the forces and temperatures associated with rim brakes. and both know roadies eat that shit up like hotcakes, and second (speculation) was to pressure the UCI to allow them for competition.
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Well, I am going to ride up Teton Pass tomorrow, and see if I can break 55 on my new bike.
But I don't have a computer....
But I don't have a computer....
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As of right now, disc setups have a 'tad' more wind drag than rim brakes...but I am sure they are working on it as we type.
and they will slice you up when the peloton crashes
no more than bladed spokes will. Or, you know, crashing in the pavement at 25mph+and they will slice you up when the peloton crashes
What's the reason for short roadbikes then? It's not like they need to be super agile or am I missing something? Seriously I have no clue about roadbike geometry.
Also I have never said I worked out how to improve handling. Remember I wasn't the one who started this topic. You have misplaced your annoyance here. I'm just curious why the proposed ideas won't work. Also I ride road bikes. I use one to get to work. I just don't think about them too much.
Also a *sigh* is as emotional as brits get, isn't it?
The one claimed by a crashed rider and then hyped by the media event turned out to be a normal racing accident with chainring involved. Strangely enough the media was not reporting that as loudly as the disc cut story.and they will slice you up when the peloton crashes
Ever seen one of those drunken footbal bois?