How much “better” are carbon rigids than Steel rigid forks?

Obviously they’re quite a bit lighter, and I’m assuming they’re better at absorbing some trail buzz, but how much better? Am I likely to notice it with a big tyre up front, or is it mainly for people running skinny tyres too that it makes a difference?

Oh, and is an Exotic Carbon fork for £100 off ebay as good (or at least nearly as good) as an expensive Pace or DT Swiss Carbon fork?

FWIW, just put a cromoly rigid on my hardtail the other weekend, first time I’ve ridden rigid in about 15 years, and quite enjoyed it actually. Not planning on selling my suspension fork, but thinking of swapping about a bit at least.

Not all steel or carbon forks are the same.

My on one carbons are nicely compliant. Too long since I rode steel unicrowns but my memory is that they are way stiffer. Weight difference not nec as much as you’d think.

I’m not convinced carbon is better. I much preferred the ‘feel’ of the steel forks I had before my carbon Exotics. The exotics are undeniably lighter however.

Obviously they’re quite a bit lighter

On-One carbons are a 970g (£175), Singular Steel forks are 1100g (£40 off someone who doesn’t want/need them on the classifides or I think some people got them new from singular) so that’s almost £1 per gram saved, which is about where most people draw the sensible limit line.

They still hurt hitting things on the trail, but I’ve found them suprisingly comfortable, certainly better than a cheep suspension fork in anything other than steps in the trail (they feel far worse falling into something and landing suddenly than hitting something of a similar size, guess that’s partially due to the 29er wheels rolling over stuff, but being no better at being dropped onto a flat surface.

Just had white brothers rock solids fitted, amazed how comfortable and smooth they are, obviously very light too.

Current rigid is a Genesis Cromo straight blade fork, weighs 1200g

Thinking of either a 2nd hand Pace, or a 2nd hand On One carbon fork or similar. Understood the Pace to be around 750g or so, the On One only slightly heavier.

Not too bothered about weight, more just thinking would a Carbon improve the ride experience or not?

That genesis fork wasn’t as smooth as some tapered ones I had done, one became the fortitude fork. About 950g ? and more comfy. But more flex. Personally, although not a common pov, I don’t like comfort coming from much fork flex. A bit is ok but it can work against you too.

Light Carbon Forks

Too Many variables to give a definitive answer. What do you want the fork to do, how string does it need to be. The old high end steel unicrown forks were 6-700grams i seem to remember. But so much is now built to a price and marketed rather than built to a weight.

Old steel forks were shorter and v-brake only. No cen then either. That could explain some weight advantage, but I’m sure ypu could get a good custom steel fork at close to that weight still.

I’ve got 415mm axle-crown Project 2s and compared to 420mm RC31s the difference is pretty marked. The carbon forks are significantly smoother over the trail. However, as folk have already said, not all carbon forks are created equal.

What do you want the fork to do, how string does it need to be.

Don’t want flex, just wondering if they do noticably dampen trail buzz. Much in the way a decent carbon bar can. I’m beginning to think that the narrower the tyres (ie. road bikes) are, the more difference it will make. The 2.4″ Rubber Queen on a 35mm rim setup tubeless run at about 15-16psi will probably make a huge amount more difference, but if a carbon fork is any better it might be nice.

Think I’m noticing that at 450mm long, the current fork is still probably nicer to ride than the last time I rode a rigid which would have been about 390mm.

However, as folk have already said, not all carbon forks are created equal.

Sure, and this is what I wanted to know. Thinking maybe if I could find a decent 2nd hand pair of Pace RC31’s in the right length at a good price it would probably be worth it, at least way more so than an Exotic or On One fork.

Don’t want flex, just wondering if they do noticably dampen trail buzz

How do you think they ‘dampen trail buzz’ if not by flexing?

How do you think they ‘dampen trail buzz’ if not by flexing?

As a frame designer, I’m assuming you’re joking…

Either that or you are TJ in disguise and I claim my £5! 😉

I’ve got a set of Salsa CroMoto and Nukeproof Carbon (same as Exotic I believe). I’ve used both on a Rock Lobster team tig SL (with same wheels and tyres) in the Yorkshire Dales for XC and I def prefer the Carbon over croMoly steel. I found a much nicer ride, could go a bit faster, wrists/hand weren’t shot after a long ride.
The only downside was, at under 20lbs, I was getting pinged all over the place on descents, so added some heavier wheels and tyres to get a bit more weight behind the bike, which worked/felt better.

They very much do flex, if you look down at the forks when descending or braking, it’s very alarming!!

News just in, second hand on the forums is cheaper than buying in the shops.

On-One carbons are a 970g (£175), Singular Steel forks are 1100g (£40 off someone who doesn’t want/need them on the classifides or I think some people got them new from singular) so that’s almost £1 per gram saved

£175? Where did that number come from. They’re £150 at the moment, got mine for £100. Weighing them now they’re 945g with 180mm brake adapter and a crown race, cut a few inches off the end.

Pretty sure you can buy OO carbons second hand too if you want.

Loving my carbons, alarmingly flexy (200lb/6’6″ rider) but they’ve been awesome. Randomly put them back on tonight actually, I’m constantly in turmoil over whether I prefer them or the Rebas.

As a frame designer, I’m assuming you’re joking…
Either that or you are TJ in disguise and I claim my £5!

Well any linear compression or extension will be negligible so if vibrational damping isn’t provided by flexing how exactly is it?

As a frame designer, I’m assuming you’re joking…

Either that or you are TJ in disguise and I claim my £5

Go back to school and learn some engineering. The only way that forks can take the buzz out is by flexing.

I’ve got Exotics. Definitely take some ouch out of the experience compared with old skool steel forks that I used back in the pleistocene. I love ’em. They’re lighter than the On One carbons and have taken some fairly serious abuse without complaint.

Go back to school and learn some engineering. The only way that forks can take the buzz out is by flexing.

Mostly, but not totally true. Materials vary in damping properties or levels of resonance just like they vary in stiffness. High frequency vibration or ‘buzz’ resonates less / disipates faster in a carbon structure than a steel one. But low frequency vibration – brake or bigger-bump flex- will be more about the overall stiffness of the fork than the material. Generalising and I’m not saying everyone will feel a difference in the fork material beyond basic stiffness, but if you can’t make a good bell or a tuning fork out of carbon fibre the same lack of vibration retention should be true of carbon bars or forks.

Pace and Salsa for me, not into carbon (tried a few)

Steel is real!!

What jameso said. Carbon Fibre has an inherent damping property in comparison to metals. Of course you can make a rigid fork that flexes lots from the stuff and it will be confused as being “forgiving”, what I want though is a stiff fork that puts the wheel exactly where I expect it to be without flex, but I was wondering if you can get this with a decent carbon fork that also takes the very fine edge off things, like a good quality carbon bar or road bike frame can.

Singlespeed Shep, any particular reason you didn’t like carbon forks as much and prefer steel? I’ve not tried a carbon fork on a Mountain Bike at all yet, my friend swears by carbon rigids making a massive difference over a steel one, I’m not convinced either way yet.

Yeah should have elaborated,

I weight 15 stone and am 6’2″ so larger than most.

I have tried Pace and Niner carbons. I didn’t notice a great deal of flex over the steel ones unless cornering. The niners flexed more than the Pace ones and I felt un-nerved by it. I also felt more confident that if I went round a corner fast and hit a rock/root etc the steel would handle it better.

The forks I Run now I do with a 2.35 (with salsa) and 2.2 (with pace) and that gives me enough comfort for trail riding on my 29ers.

Then it comes down to cost £80 for the salsa vs £150+ for carbon.

I would recommend people to try both carbon and steel, because with everything there are many options and they will suit different riding style/locations/riders

I suppose what jameso says sums it up really, I wouldn’t want my arms or body taking the effects of ringing like a bell or a tuning fork for any sustained period. Hence, probably why I much preferred the ride from carbon forks on arms and body from the same frame and tyres. work the science out from that. Also, I think it’s been said in other similar threads that not all carbon forks feel the same.

On 26″ I’ve had:
Pace RC31’s…too flexy.
On-One steel…dear lord are they harsh, & heavy.
On-One carbon…ok, stiffer than Pace.
Exotic carbon…best of the 26″ lot.

On 29″:
On-One carbon…ok, seemed to take bigger hits better than Steel.
Singular steel…loveliy fork.
Niner steel…let’s be honest here…save yourself £100 & get the Singular fork. It’s identical but for a different brake mount.)

Seems to handle bigger bumps, whereas steel is quite hard but seems to soak up smaller bumps & trail buzz.

I should probably add to my post above, with the Salsa steel forks I felt more in control on descents, certainly not being pinged off stuff or wanting to add weight. BUT, after a 3hr ride on steel forks my hands and body would know about it, like I recall MTB 20yrs ago.

B.A.Nana – Member
They very much do flex, if you look down at the forks when descending or braking, it’s very alarming!!

+1
got a set of white bros rock solids, nice and comfy but i can see and feel them moving under heavy braking. takes a bit of getting used to 😯

My first set of rigid forks for years. Used to run rigid steel forks years ago… Kenesis Maxlight IX 29’er Carbon Fork… They work very well in my opinion, but this is a 29er so not a direct comparison.

I’ve got an eXotic carbon fork on my Global Ti and it’s a dream, nice and light, stiff enough to handle well yet very smooth with a 2.2″ tyre.

You only miss suspension on big hits like steps and kerbs, on anything else you won’t miss your springs. I Ebayed my Rebas last month and won’t bother with suspension again.

If you happened to be anywhere near Blackburn you’d be welcome to try mine out.

What Jameso said, CFRP goes ‘twang’, metals go ‘ting’. Ting being the technical term for something undamped oscilating at it’s natural frequency.

Depends on the Steel forks though, On-one have a reputation for being quite harsh, but they’re nothing compared to the DMR trailblades I used to have, and my singular ones aren’t noticably buzzy, but don’t flex much either.

@ boysie – those forks are well sweet, wish I saw those before I invested in the white brothers.

EDIT – doesn’t look like they do a 26er, mind you the image on wiggle doesn’t do them any favours.

Thats a nice light looking bike boysie

Thats a nice light looking bike boysie

sod the bike, look at that lawn, immaculate.

Thanks… The forks look better in the flesh than on Wiggle. which is good as I pre-ordered them before they where available…. They ride very well and steering is also very good… Even better than wih the Reba’s so the offset and length must be about right [for my bike]

The bike itslf is based on a Scott Scale frame but with full XTR, Crest rims, with revolution spokes, Ritchey and KCNC finishing kit.

Interesting to note the 1/5 lower headset cup on the Scott is One mm different to most other makes at 55mm [most are 56mm] So the Chris King headset I bought to go with the bike was useless and the only one I’ve found that fits is a Ritchey, which I think are owned by Scott?

Ritchey, which I think are owned by Scott?

really? they now own syncros too, I was looking at the syncros fl carbon forks but couldn’t stretch to the £400+.

Mostly, but not totally true. Materials vary in damping properties or levels of resonance just like they vary in stiffness. High frequency vibration or ‘buzz’ resonates less / disipates faster in a carbon structure than a steel one. But low frequency vibration – brake or bigger-bump flex- will be more about the overall stiffness of the fork than the material. Generalising and I’m not saying everyone will feel a difference in the fork material beyond basic stiffness, but if you can’t make a good bell or a tuning fork out of carbon fibre the same lack of vibration retention should be true of carbon bars or forks.

Apologies for the snarky response. Bad day.
This was what I should have replied with and thank you for clarifying.

I doubt that most people will feel the difference between the residual oscillations of steel and carbon. I would think that it is the initial displacement that dominates the “feel” of the fork and this is mainly dictated by the diameter of the tubing involved. To give an example, a surly fork, despite being longer, will feel stiffer than a p2 fork, the same principle of stiffness varying with (approx) square of diameter are behind the lefty and SUB forks. The difference in the two is predominantly in the later oscillations – the ringing as it were – which is a small vibration, vastly masked by subsequent impacts.

FWIW, my own personal preference is for steel but mainly due to failure modes – I have bent P2s when a carbon fork would have snapped.

Good thread this Mark. Am currently building a rigid 29er and humming and haring between Carbon Exotics and Steel Salsa forks.

for those claiming more flex = more damping…

Carbon fibre tennis racquets are stiffer than the old aluminium ones but damp the vibrations much better. Same with modern composite axe handles.

Flex does not equal damping. Damping is the ability to dissipate energy. Flex is related to the stiffness of the material and the structural design.

I’ve got a set of carbon Exotics- they’re light, and seem strong enough, they’ve been beaten about. They also seem to be exactly the same as at least one other far more expensive fork mentioned in this thread 😉

They flex mentally on the brakes though- I combined them with an Airotor and watching the forks judder back and forth was pretty alarming. So I stopped looking.