I’m in the market for a gravel road bike. I am looking at the Salsa Vaya Ti. Salsa is producing a gravel road “racer”, the Warbird, for 2013. One of the geometry differences is a shorter chain stay and lower bottom bracket. All other factors held constant can a calculation be made regarding the average speed given the same wattage with a specific geomotry variable?
To put it more plainly, how much inherently faster will the Warbird be than the Vaya?
Thanks for your thoughts.
Josh
No, of all the variables in bicycle design, chainstay length and BB drop would be two of the hardest to associate with speed differences. Basically shorter chainstays will change the weight distribution between the front and back wheels and the straight line tracking characteristics and lower BB will impact the center of gravity and things like pedal clearance but will not directly impact whether one bike rolls faster.
In general if everything else is the same in terms of head tube angle, fork offset, wheels and such you’d generally expect the bike with shorter chainstays and shorter overall wheelbase to be more lively and respond more quickly to steering inputs which also means twitchier but that doesn’t make the bike ‘faster’ in the sense of holding higher speeds for the same effort or power. Other than gross weight differences the biggest thing that will impact that is differences on how the rider fits on either bike and what that means in terms of position and aerodynamics and of course what wheels and tires you run on each bike. But if you’re going to ride fairly upright on either ‘gravel bike’ then it doesn’t really matter.
Buy the one that fits best or if you can get a good fit on either, the one you like the best after a test ride.
-Dave
Thanks for your thoughtful response. I appreciate it.
Josh
actually a lower bottom bracket will make the bike feel more responsive. there are several reasons for this from lower center of gravity and will be more pronounced if you rock the bike when standing on the pedals.
however, I agree with previous poster that overall fit and handling is more important. the vaya looks more like a touring bike which is more relaxed. I don’t see the warbird so can’t comment directly on that. There a lot of bikes now being made for gravel riding. For my two cents, I’d go with a Hampsten Strada Bianca.
In theory a lower BB should result in better aerodynamics. I believe thats been found true in a WT but couldn’t put my fingure on the figures. In practice its going to be tiny.
Lower bb feel is tricky. One the one hand it should feel more stable on downhill curves with the lower cg. One the other hand for tight crit type curves a high cg will make the bike feel tippy and more willing to turn. So depending on whay your individual preferences are it could feel better or worse.
For a fast gravel road bike I’d go low BB / clearance for big tires (at least legit 28mm, 32 mm would be better) and a slightly higher Headtube. Of course you have to make careful measurements as lowering the BB makes the stack height higher.
I have not heard of a gravel road bike. Wouldn’t a cross bike be pretty good for this purpose?
Why not just add some 28mm tyres to your road or CX bike?
Good questions, but realistically there will be no measurable differences regarding watts in/mph out (assuming all other things being equal of course).
Those geometry differences are going to have much more of an effect on tire clearances, your final fit on the bike, the bike’s handling, the quickness of the steering, how harsh the ride will be, and how much energy the bike will require of you to keep it going in straight line.
I also have a ‘gravel bike,’ but it was a custom build up (with a stock frame) and what I find makes the most difference regarding speed is fit on the bike, the tires you choose, and suspension (or lack thereof).
Once again, thanks for all the thoughtful responses. I looked at the Hampsten Strada Bianca. Beautiful bike!
I’m in the market for a gravel road bike.
My Cervelo R3 does a nice job on gravel roads and even some light CX use.
Read last paragraph of THIS blog post.
Picture of my R3 in gravel/dirt-mode with wider tires and MTB pedals.
My Cervelo R3 does a nice job on gravel roads and even some light CX use.
That’s a great bike.
But using an R3 in this kind of application depends hugely on exactly what kind of dirt roads you might be riding on. As there are some where riding a bike like that will result in all your fillings getting knocked out. :^)
Shorter chainstay will put more weight on the back wheel – good to lighten the front so it doesn’t dig into looser gravel, good to keep traction on the rear wheel. Of course going with a wider front tire would do much the same thing. But shortening the chainstays also shortens the wheelbase, which will quicken the steering.
Lower BB will make the bike less reactive to weight shifts when standing, so less squirming around.
But these wouldn’t have any affect on raw speed, I would think.
Thank you Steve. I actually emailed you a couple months ago and you responded, thanks. About that blog post, I tried gravel with my Soloist with the largest tires that would fit. It really didn’t cut the mustard for me.
I want to train up to do longer gravel races/rides so, I think a dedicated wide tire machine might be fun to ride. (It can also be an equalizer when I ride with my son.) I spent 3 hours on gravel yesterday on a Vaya TI with the goofiest handlebars. Other than the bars the gravel was a hoot! Much slower than any road riding and the rolling hills here in Iowa kept the heart rate up. Chased by one black lab twice saw 3 regular hawks and 2 black hawks.
My concern is that the new product from Salsa will be significantly faster than the Vaya. From what I gather, fit, tire choice, among other things will factor in to the inherent speed question.
Thanks a lot for the responses.
After looking at the Salsa website and what they’re pitching as ‘adventure bikes’ I’d just get a good cyclocross bike and mount it with tires appropriate for the surfaces you intend to ride. Cross bikes are fun, fast, can be ridden with slick road tires or aggressive knobbies depending on where you’re going and are available from many manufacturers across a range of price points depending on how much you want to spend.
No reason to limit yourself to a few defined ‘adventure’ or ‘gravel’ bikes which limits your choices and based on the posted geometries and components are basically cyclocross bikes but at least those equipped with caliper brakes are somewhat limited in terms of tire choices where if you go with a cantilver or disc brake model you basically have a cross bike.
-Dave
Dave,
Agreed.
These seem to be sub-sub specialty bikes. Nothing wrong with that, but a straight up cross-bike in the garage is never a bad thing. They can be ridden on roads - gravel, dirt or paved, on rail trails, even on light off-road trails and pushed pretty far. ( you should see how far I’ve pushed the R3!!)
Riding on gravel on a standard road bike even with 23mm tires is old hat for me. For some of the best riding in my area at home and out our recreational property, it’s a regular occurrence to ride at least 5 - 10k on good gravel/dirt roads. Heck, at the cottage we start and finish every ride on 1k of gravel.
Strangely this act ( riding on gravel) puts absolute panic in the hearts of many triathletes and cyclists. It’s a skill/art that is easy to get and will expand your skill set and where you can ride!
My Cervelo R3 does a nice job on gravel roads and even some light CX use.
That’s a great bike.
But using an R3 in this kind of application depends hugely on exactly what kind of dirt roads you might be riding on. As there are some where riding a bike like that will result in all your fillings getting knocked out. :^)
That’s not a gravel road and no road oriented bike should go there. Your best bet would a hardtail 29er with a lockout fork.
I have not heard of a gravel road bike. Wouldn’t a cross bike be pretty good for this purpose?
Was going to post almost the exact same thing.
Seems like the bike companies are inventing another niche market for which a solution has long existed.
I road some miles on the great divide bike route . Lots of gravel . Cross bikes are nice but still not as comfy as a big tire 29er ,low preasure tubeless. Buy both and have fun.
Thom
Cross bikes are nice but still not as comfy as a big tire 29er
Absolutely.
I had not been on a really great MTB bike in years - nor had much experience riding an MTB bike in real off-road terrain for a long time. At Interbike Demo Days last year, good friend Melanie McQuaid suggested that I join her on a ride with Specialized Dealers that she was leading, “for fun”! Mel, got me set up on Specialized top-of-the line full carbon, duel suspension 29’er in my size.( If you think tri-bikes are expensive, after-the-fact analysis revealed the MSRP on this bike to be $11,000!!) That bike could make anyone ride like a hero. I was riding up and over terrain that I had no right to be riding on given my limited experience riding MTB bikes. The thing was amazing and really opened my eyes as to what you can do on the state-of-the art MTB bikes.