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Cyclocross and Gravelbiking (Recreational) This has to be the most physically intense sport ever invented. It's high speed bicycle racing on a short off road course or riding the off pavement rides on gravel like : "Unbound Gravel". We also have a dedicated Racing forum for the Cyclocross Hard Core Racers.

Gravel Bike Geometry Analysis Paralysis

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Old 07-23-20, 01:31 AM
  #26  
Duende108
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Originally Posted by chas58
Huh, that is interesting. Does that come from test riding bikes, comparing geometry, or changing forks? Personally, I can't tell the difference in a couple of MM. Takes about 5mm for me to really feel anything different. But rake by itself means nothing.
yeah... I shouldn’t have been so dramatic in my wording. Not much of a change from 47mm to 50mm as an isolated change.

However, if you consider that along with the head tube angle change and other mods... I think the feel would be significantly different.
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Old 07-23-20, 08:57 AM
  #27  
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Originally Posted by HTupolev
A big part of it is that the wide stance on the handlebars gives the rider a ton of leverage on the steering. Geometries that are excessively weighty and floppy in road posture with 42cm drop bars can feel natural in an MTB posture with 80cm flat bars.
Well, I wouldn't put it past the marketers to push wide handlebars for quicker steering and then slacken the geometry to compensate. But I'm pretty sure they slackened the head tube for the reason I stated. The owner of my LBS got ridiculously wide drop bars for his gravel bike because he's used to the width.
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Old 07-23-20, 09:56 AM
  #28  
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Originally Posted by unterhausen
But I'm pretty sure they slackened the head tube for the reason I stated.
It's certainly a part of it. Another reason for achieving high trail with a slack head angle is to create a large front-center, to keep the rider feeling "behind" rather than "over" the front wheel without needing to use a problematically-low bottom bracket.
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Old 07-23-20, 05:55 PM
  #29  
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Originally Posted by HTupolev
It's certainly a part of it. Another reason for achieving high trail with a slack head angle is to create a large front-center, to keep the rider feeling "behind" rather than "over" the front wheel without needing to use a problematically-low bottom bracket.
Couldn’t you just lengthen the top tube and keep the steering angle the same, like Cervelo did with the Aspero? Front end geometry is the same on the Aspero as it is on the Stigmata, just with an extra 10cm added to the top tube.
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Old 07-23-20, 06:39 PM
  #30  
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Originally Posted by Phatman
Couldn’t you just lengthen the top tube and keep the steering angle the same, like Cervelo did with the Aspero? Front end geometry is the same on the Aspero as it is on the Stigmata, just with an extra 10cm added to the top tube.
If your only goal was increasing front center, yes. Although at a certain point you start to run into difficulties of what bars and stems are available.

But if you're intentionally trying to use a higher-trail geometry as well, and especially (if as unterhausen suggests) you want a slacker head angle for reasons of suspension behavior, then slackening the head angle is just one of many decisions that can all make sense alongside each other.
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Old 07-23-20, 06:50 PM
  #31  
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Originally Posted by Phatman
Enh, reviews aren't foolproof either. If the person paid for their bike, they won't trash it too much because it makes them look like an idiot for spending too much money on something that sucks. If they get it for free, they'll DEFINITELY not tell you if it sucks...because they want to keep the flow of free stuff coming.

Math and test rides, man. Math and test rides.
You are correct, reviews are just one tool in your fitness arseeenal. My biggest issue is always top tube length. I am 5 nine and a half with short stubby legs and a very long arms and torso. I will scrutinize the numbers but the big deal maker/breaker is top tube length. On most bikes that fit my stubby legs I am jammed up on the top tube. That is what I look for, reviews and I want to know how people fit relative to the stated top tube length. If I have enough standover clearance and top tube everything else is negotiable. This is for gravel bikes which tend to have a more relaxed geometry than road bikes.

Here is something I suggest: Don't fall in love with a bike until you actually ride it. Whenever I buy a bike over the internet I mentally prepare my self for the disappointment of it not fitting. Of course doing all your measurements, math, and due diligence are going to increase the chances that the bike will fit.

Of course a longer stem might do the trick, but you don't know for sure until you test ride.

Last edited by RadDog; 07-23-20 at 07:01 PM.
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Old 07-23-20, 10:08 PM
  #32  
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Originally Posted by Phatman
Couldn’t you just lengthen the top tube and keep the steering angle the same, like Cervelo did with the Aspero? Front end geometry is the same on the Aspero as it is on the Stigmata, just with an extra 10cm added to the top tube.
I'll admit, I don't have a total understanding of the finer nuances of geometry, and their effect of ride characteristic, but I do know that the Aspero is an incredible bike...Cervelo really nailed it. And I highly recommend you taking a hard look at it.

Another option is the new Cervelo Caledonia that was just release today...if you don't need/want massive tire clearance. If it was available a couple of weeks ago when I bought my Aspero, trying to decide between the two would have been quite the dilemma.
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Old 07-24-20, 07:03 AM
  #33  
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Originally Posted by melikebikey35
I'll admit, I don't have a total understanding of the finer nuances of geometry, and their effect of ride characteristic, but I do know that the Aspero is an incredible bike...Cervelo really nailed it. And I highly recommend you taking a hard look at it.

Another option is the new Cervelo Caledonia that was just release today...if you don't need/want massive tire clearance. If it was available a couple of weeks ago when I bought my Aspero, trying to decide between the two would have been quite the dilemma.
The Aspero is on the shortlist. Or long list. Or ever-lengthening list, as it seems. The only shop that sells them in town is only allowing "concierge" type shopping though, where you have to call ahead and they'll bring it out to you, I kinda feel bad if they prep this bike all up for me to look at and I don't like it. Maybe I'll just have to get over that.

Definitely not interested in the Caledonia at all, I want to run 42mm tires. It seems more aimed at the Euro crowd that doesn't have any gravel, but sometimes hits some cobbles as they ride through the small towns where they're going to stop at for "cafe" with their legs crossed at their thighs. Its a nice looking bike for sure though.
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Old 07-24-20, 07:39 AM
  #34  
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Originally Posted by Phatman
A few years ago, I bought a Toyota Tacoma because I thought it would be a perfect "middle" type vehicle, I could haul with it, but I could park it in the city easily, road trip with it, etc. I hated it! It got crappy gas mileage, rode and handled badly, couldn't carry a load of compost without the axle sitting on the frame, etc. Basically, it had all of the downsides of a full size truck with none of the upsides of a car. I traded it after 6 months and lost thousands of dollars.
A lot of people over think things
I can give some food for thought for this part.

A "compact SUV" that can tow 2000-3500 lbs which is pretty much all of them (Escape, CR-V, CX5, Suburu, Rav4 etc) and a utility trailer. You can avoid the pickup truck premium price. A 5x8 landscaping utility trailer is $700 and a little work you can put 16 inch sides on it. You can get your decent gas mileage and car like feel at other times and hook up the trailer and pile on 2 yds of mulch (averages 800-1000 lbs a yard), lumber, garbage, couch, washer/dryer etc. They are easier to load and unload because of their height and ramp, larger than almost any truck bed, you can leave the material in them not tying up your vehicle giving you some time, you can pull them around your yard with a garden tractor or push it with a second person, you don't have to worry about damage to your vehicle or bed when the front end loader drops a load of gravel in it from 8 feet high, no vehicle sag when pulling a load. Downside for some people, you need a place to keep a trailer and suddenly other people will want your help or to borrow it or the worst is they will ask you to help them move!!! You can take this concept a little further and use the roof rack and a hitch mounted cargo hauler for a lot of things too. You can turn that compact SUV into quite a utilitarian thing.

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Old 07-24-20, 11:21 AM
  #35  
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Originally Posted by Phatman
The Aspero is on the shortlist. Or long list. Or ever-lengthening list, as it seems. The only shop that sells them in town is only allowing "concierge" type shopping though, where you have to call ahead and they'll bring it out to you, I kinda feel bad if they prep this bike all up for me to look at and I don't like it. Maybe I'll just have to get over that.

Definitely not interested in the Caledonia at all, I want to run 42mm tires. It seems more aimed at the Euro crowd that doesn't have any gravel, but sometimes hits some cobbles as they ride through the small towns where they're going to stop at for "cafe" with their legs crossed at their thighs. Its a nice looking bike for sure though.
Yah, the shop that I purchased mine from was doing online sales only, so I didn't even get to see the bike before I bought it. I wouldn't worry about it...in this market, if you don't buy it, someone else will be right behind you.

I think that the Caledonia is capable of a lot more than that. Me, for instance, I've been running 35mm semi-slick tires for the vast majority of my gravel riding, so I could run the same setup on the Caledonia, and do the same rides, but get a bike that has a bit more road-focused geometry, is ~300g lighter, and has better aero properties. I also use my gravel bike (with road wheels) for my casual/zone 2 rides, which is basically what the Caledonia is designed for.

Overall, I'm very happy with the Aspero and don't have any buyers remorse/wish-I-would-have-waited thoughts, but if both bikes were available at the time of purchase, there definitely would have been some hesitation on my part.

But, yah, if you want bigger tires, then the Caledonia is a no-go from the start.
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Old 09-21-20, 09:46 AM
  #36  
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Well so after all of this analysis paralysis, I test rode 0 bikes, remained frozen in place, and then just ponied up and bought a Specialized Crux. First, I'll start with what it doesn't do. It is way too close for comfort using a Specialized 42mm tire on a 21mm internal rim. The space between the stays is 49mm measured, and a 42mm tire that measures ~44mm was just way too close for comfort. However, a Specialized Tracer 38 on a 21mm internal rim is right at 40mm actual, and fits in the stays nicely. I can pass a 4mm allen wrench around all sides of the tire, and I think that's probably okay.

As for the geometry, I've got no regrets on going with the lower trail. I did my favorite gravel loop, which is about 2600' of elevation change in 28 miles and is about 25% road and 75% gravel. Climbing was rock solid, no wandering, and while the handling was quick, I never thought it felt twitchy. Overall, its awesome awesome awesome, like a gravelly crit bike. I still need to cut the steerer, get the hoods/bar angle right, and see about getting my Easton's swapped over from my Kona, but basically I'm thrilled.

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Old 09-21-20, 04:12 PM
  #37  
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Sweet, that bike was my runner up. I didn’t get it, but got something similar. I love it. Climbs like a goat.

IMHO, bikes are not twitchy, stiff armed riders are. ;-) I do find a bike like that loves to dive into a turn – which is great on tarmac, but I need to consciously turn in slow on gravel. I don’t know what your fork clearance is, but you probably still can get that 42mm tire in up front (maybe bigger?)

I love a gravelly crit bike!!!
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Old 09-22-20, 06:47 AM
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Originally Posted by chas58
Sweet, that bike was my runner up. I didn’t get it, but got something similar. I love it. Climbs like a goat.

IMHO, bikes are not twitchy, stiff armed riders are. ;-) I do find a bike like that loves to dive into a turn – which is great on tarmac, but I need to consciously turn in slow on gravel. I don’t know what your fork clearance is, but you probably still can get that 42mm tire in up front (maybe bigger?)

I love a gravelly crit bike!!!
What did you end up getting? I tend to agree that a lot of the handling comes down to the rider. I'm not sure why I didn't think about this before, but having ridden on the road for so long, I'm used to quick handling bikes. I almost wonder if I was just half a beat ahead of the Kona, and it just wasn't responding quick enough, so was overcorrecting and that caused the wobbling on climbs? Or maybe it was the extra flop from the increased trail? Who knows.

And yeah, plenty of room in the fork for a 42, might swap the front to the rear when the rear wears out, and then put a 42 in its place on the front. Also, I didn't mention this before, but the Specialized Tracers are ******g awesome. Nobody seems to have reviewed these, but they're excellent tires, on par with Maxxis Ramblers for sure, and they use the same bulletproof casing as the Pathfinder.
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Old 09-22-20, 09:45 AM
  #39  
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Originally Posted by Phatman
What did you end up getting? .
I was looking at a used crux. Pretty high end - it was a the shop owner's bike, a couple of years old, and pretty sweet. I think it was $5000 new? I wasn't too fond of quick release with disk brakes though.
For about the same price, I got a new Canyon Inflite. It was about the same price as the used Crux as I recall. Riding wise, they have the same dynamic. Having a 17.5lb gravel bike is a lot of fun (its about 16.5 with my road tires/wheels). I love the way they both really pop on acceleration, and have handling that makes me smile. Getting down in the drops and ripping through some tight twisty single track is a new experience.

Two things that I had to get used to with the Inflite:
- the steering is razor sharp, and it would turn a lot tighter and more precise with the same input than I was used to.
- the rear is so compliant that at first I would get off the bike to check my rear tire to make sure it wasn't losing air. ;-)
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Old 09-23-20, 12:27 PM
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Originally Posted by chas58
I was looking at a used crux. Pretty high end - it was a the shop owner's bike, a couple of years old, and pretty sweet. I think it was $5000 new? I wasn't too fond of quick release with disk brakes though.
For about the same price, I got a new Canyon Inflite. It was about the same price as the used Crux as I recall. Riding wise, they have the same dynamic. Having a 17.5lb gravel bike is a lot of fun (its about 16.5 with my road tires/wheels). I love the way they both really pop on acceleration, and have handling that makes me smile. Getting down in the drops and ripping through some tight twisty single track is a new experience.

Two things that I had to get used to with the Inflite:
- the steering is razor sharp, and it would turn a lot tighter and more precise with the same input than I was used to.
- the rear is so compliant that at first I would get off the bike to check my rear tire to make sure it wasn't losing air. ;-)
Ah, gotcha. Well on the Crux, you definitely know there's air in the tires! Just kidding, it does ride better than my Kona, but its not a super duper cushy ride. Again, gravelly crit bike.

This one is the cheapest build, the Apex1. You get the Sworks frame with it though, just with lower end parts. It seems like a really good value at $2800. I swapped the crank from my Kona and I've got to file down the front hub endcap to get my Easton's on, but honestly, the Apex works really really well. An 11-42 cassette is incoming, I hope I can fit the cassette without swapping my chain!
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Old 09-27-20, 08:41 PM
  #41  
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Originally Posted by chas58
I was looking at a used crux. Pretty high end - it was a the shop owner's bike, a couple of years old, and pretty sweet. I think it was $5000 new? I wasn't too fond of quick release with disk brakes though.
For about the same price, I got a new Canyon Inflite. It was about the same price as the used Crux as I recall. Riding wise, they have the same dynamic. Having a 17.5lb gravel bike is a lot of fun (its about 16.5 with my road tires/wheels). I love the way they both really pop on acceleration, and have handling that makes me smile. Getting down in the drops and ripping through some tight twisty single track is a new experience.

Two things that I had to get used to with the Inflite:
- the steering is razor sharp, and it would turn a lot tighter and more precise with the same input than I was used to.
- the rear is so compliant that at first I would get off the bike to check my rear tire to make sure it wasn't losing air. ;-)
I love my inflite! I just swapped the 33s for 38s, didn't notice much difference tbh. Took it for a 50 mi mostly gravel ride today with 2900 ft. It climbs like a rocket and tears through descents, feels predictable and very lively.
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