Hi,
Wondering peoples thoughts on the compliance benefits of a carbon seat post and stem over alloy for a titanium gravel bike? I like Thomson products although they don’t do carbon in either of these (not a setback seat post). Any advice and/or alternative recommendations would be much appreciated.
Cheers,
I can’t talk much about the front end but in the rear carbon compliance is totally a thing. When I switched from alloy post to a carbon one (canyon vcls s13 vs. ritchey wcs both with setback) the difference was pretty huge over cobbles and rough terrain.
I would stray away from Thomson if you are looking for comfort. All lightweight aluminium posts tend to be pretty harsh and Thomson posts especially.
I’ve been running a Voodoo Juju gravel bike for somewhere around 5, 6 years now, as a daily driver, tourer, and go anywhere bike. Standing up and stomping on the pedals, especially when setting off from stop lights, you can feel the frame flex a little, as it soaks up the initial effort, before converting it into forward motion.
Swapping an older alloy seatpost for a Roval Alpinist, you can just about detect the seatpost flexing a little over the harshest stuff (i.e. deeper potholes, low height curbs, etc), without giving away too much stiffness.
Overall, I like the balance, where the overall package is still a biased a little towards the stiff end of the spectrum, but there’s still enough flex to provide some comfort so you don’t get too beat up.
Some days, I do wish for the frame to be a little stiffer, but overall, it’s a great bike for longer distance, get away from it all/clear your head rides.
PS. YMMV, but I’ve been told the Elita One Pro seatposts are pretty decent as well.
A carbon seat post can be significantly more comfy. I write “can be” simply because carbon can be engineered to have certain stiffness in certain directions. On my hardtail this makes a significant difference.
As for handlebars, see above for stiffness, but I can still perceive a difference between the alloy and carbon versions of the same 3T handelbars. The carbon handlebars soak up higher frequency road buzz better.
There are two things at play: compliance and vibration damping.
Carbon can - if designed in such a way - offer both.
Alloy will offer very little compliance. But f.i. Spank is succeeding in reducing vibrations in alloy handlebars by injecting them with a special foam. (I have my own experiment ongoing.)
On my own Ti frame I have an Ergon ‘spring bladed’ seatpost, and I do like the effect of it. And despite having a suspension stem, I found that a carbon handlebar was also a plus. Especially in terms of vibration damping and to some extend - in the drops - also in terms of compliance.
Because of peace of mind, I reverted to an alloy handlebar and I am now trying to reduce the small vibrations that still come through the bars, because they are both annoying and fatiguing.
I wouldn’t count on a regular stem in carbon to help a lot, as will be too stiff and short to really make a difference. The stem part of an integrated handlebar can be designed differently, so I have more hope there.
I have a titanium road bike (older No 22 Great Divide) with a Thomson Masterpiece seatpost. I have experimented with carbon and alloy handlebars on it.
My frame is so compliant in the rear that it took me a long time to get over the feeling that I was riding with a flat rear tire. I do not believe a seatpost will make any difference for me, but your frame could be stiffer. I also have relatively little exposed seatpost, so not much room to flex for a carbon one. I’ve got a fairly compliant carbon seatpost on my gravel bike (Easton EC90) and I personally find the frame makes a much bigger difference.
Handlebars on the other hand made a HUGE difference to me. Carbon are much more comfortable, with minor differences between models.
I’ve always been an alloy stem person, so can’t help you there.
Thanks so much for the detailed replies, really appreciated. The frame is an Enigma from the UK so should be well built and ideally compliant. Might keep looking for a carbon seat post with potentially Zipp as an option. I was thinking of staying away from carbon bars in case it was dropped/crash whilst touring with the thinking that carbon would come off second best to alloy.
As for Thomson their post and stem did get me through 12,000kms in Africa but it was on a Surly Long Haul Trucker so pretty different set up.
Again really appreciate the insight. Thanks.
If you really want compliance then IME you need to use a seatpost designed to flex, like Ergon/VCLS, Redshift or other suspension post, lightweight Ti, etc. At the other end Redshift stems definitely work, but anything rigid not so much. Also, many “carbon” stems have been alu wrapped with carbon, which manage to both weigh and cost more than straight alu.
I built an Enigma Echelon last year. The first big ride was to the Roubaix Challenge sportive where I did the long distance (so all the cobbles). I opted for a Ritchey WCS ProFlex (or ProLogicFlex… or something with “Flex” in the name). It was hard to find, and I had to source from Germany, but I’m happy with it and the bike was excellent for the ride.
I have not experimented with alternative posts so I’m not in a position to compare on the same frame.
You won’t regret the choice of Enigma though and if you have a gravel model, it should be more compliant than my “all road” version.
There’s just so many factors to compliance that it cannot be viewed in vacuum. For example, carbon posts can be compliant but the length of exposed post + layup will determine how well it does. An Easton EC70 post with 0 setback. vs 20mm setback on my bike def feels different, with the 0 feeling more “stiff” than the 20mm.
Carbon bars also can be a toss up and not created equal. Ive seen some say Easton bars are harsh while Enve are not.
IMO carbon stems are just not worth it unless you’re chasing grams. I’d probably sooner look at a Redshift or CaneCreek if I was looking for some kind dampening there.
I currently have a steel gravel bike that is pretty harsh. Moving to a Roval terra seat post and Redshift stem helped noticibly.
I’m moving to a custom Ti gravel bike soon and we’ll see what the kind of compliance the builder worked into it, but I’m planning on keeping the seat post and stem.
Some other options: Vecnum stem (parallel movement) and the Use Vybe stem.
Get a flexi carbon post and stem/bar - comfort = speed if you’re going more than 20 miles. Lots of good options on the market - depend on if you want bling or Chinese cheap. You’ll absolutely feel a difference over AL or even Ti.
If you’re considering one of the Ergon/Canyon VCLS seatposts, see if you can try it somewhere before you buy. Depending on your weight and pedaling style they can feel a little bouncy at high cadences. I have one and get along with it really well, but it took some getting used to (and smoothing out my high cadence pedaling). Possibly also worth noting that the setback version feels a little bouncier to me than the zero setback version, probably because of the shape of the spring “leaves”.
If I recall correctly you also can’t put a di2 battery inside - which was why canyon endurace had to take the bottom bracket off to reach the battery - wonder if there’s a better solution to that.
The battery can just live lower down in the seat tube; I’ve seen images where people put the battery in bubble wrap, and add a loop so it can be hooked and removed with a spoke.
Re Ergon posts: I have the offset version, and despite being a lifelong spinner have never noticed any bounciness. This may be one of those things like seat bag sway where some are hypersensitive and others don’t care; I was fine with a Revelate Viscacha but some others hated them for that reason…
I can second/third/fourth carbon seatposts in particular being able to damp enough vibration that I notice. And echoing others, that’s a matter of product selection (posts designed to do that, do it — posts designed not to, don’t). Maybe it’s my imagination at this point, but those Thomson posts really do… not… flex.
I don’t think they can flex… the fatigue behavior of aluminum is such that a flexy aluminum seatpost would just fail I think.
When I was still mountain biking, Thomson had the reputation of making the stiffest seatposts. Which was considered a good thing.
If you want matchy matchy with your frame, go alloy or titanium stem and seatpost. Carbon seatpost has more comfort. Roval Terra is a good one, but it has a little setback. For stems, I’m 100% alloy.
Thomson has a carbon seatpost. They don’t make it, though.