OK, so it’s a slightly weird question and of course comes with certain caveats like “the rider” being the obvious answer.

As some of you may have seen me and a mate are doing some Spring Classics riding in Belgium next year. My plan was to do it on a recent purchase of a CX500 Merida Cyclocross bike.

But i’ve come to the realisation (again, i know) that riding position just doesn’t do it for me. In the last week i’ve developed pain in various parts of my body which i NEVER get when using the 29er HT. But lets not get hung up on that for now, that’s not changing…. the bike is.

So lets assume i’m going to use a 29er HT (Happens to be a Parkwood in this instance) for the event, what’s the thing that’s going to give me a bit ‘more’ in the way of speed.

So things i can’t/won’t change. Frame, bars.

things i’m happy to change.
wheels, tyres, forks

Which of these is likely to give the most benefit for an increase in performance.
WTB i27 wheels
Maxxis Crossmax 29×2.25
Rockshox recon TK silver.

I’m unlikely to swap ALL… but 1 or 2 of the 3, potentially. I’m thinking say, a set of Chinese carbon forks.
https://www.ebay.co.uk/itm/100-15mm-Thru-Axle-Carbon-Gravel-Bicycle-Forks-CX-Cyclocross-Bike-Carbon-Forks/254061796396?ssPageName=STRK%3AMEBIDX%3AIT&var=553659513770&_trksid=p2060353.m1438.l2649

then a pair of CX tyres/commuter tyres….

But would these things give an actual performance benefit ?

Sticking both of the above would give me about 1.5kg off the weight of the bike of course, but that’s still leaving it at about 11kg..

(yes i know aero plays a massive and likely the biggest factor, but that’s not going to work here…so we have what we have… )

not be cheaper just making the CX bike fit ye properly?

to answer question though, rigid forks and the thinnest slicks you can get will most likely add the most speed.

No idea how heavier your wheels are, but that’ll make a difference too, but as well starting with tyres firstly, as that’ll remove a load of rotational weight and roll best. Probably most bang for buck.

Fork you’ll save a load of weight on no doubt, the recon tk is a shanner of a fork anyhow, so just fling that away regardless! 😆 go for the carbon.

Tyres I would say.  You don’t want to go too narrow as we are talking cobbles but 28mm GP4000s is my normal choice.  Before I had my road bike I had a set of wheels with narrow rims for my mtb

+1 for tyres. Something like Schwalbe G-One Speeds run tubeless would be a good call on either bike, but I’d look at riding the cross bike more – your body will likely adapt – and tweaking its riding position maybe.

Could it be when you’re MTBing you change position a lot more than road riding, so not getting the same aches?

If you go the the Parkwood, consider some barends for varied and potentially slightly more aero positions.

Could it be when you’re MTBing you change position a lot more than road riding, so not getting the same aches?

Of course, there could also be some ‘get used to it’ in there as well… But we’ve tried this before in the past few years with CX/Road bikes and i end up seeming to come back to the simple fact that, they give me problems. Usually knee based (I had surgery and repair on knee several years ago) that never seems to trouble me on the MTB, but also neck/back issues which i’m guessing is from the bars being narrower, the forearm one is a new one, but i think not insurmountable.

Riding the CX bike more could well be the answer… possibly…. maybe… ish. But i’m not feeling that idea nearly as much.

If you are only prepared to change wheels, tyres and fork, you’re not going to see major improvements in speed (assuming you’re riding a reasonable quality slick tyre) so I wouldn’t worry about it and would just enjoy the ride. Why do you need to be “faster” and how much faster would you need to be?
With your cross bike, don’t underestimate how long it can take to get your position correct. Small changes in saddle fore/aft or height, stem length/rise, bar angles can make the difference between comfortable long distance riding and ride ending discomfort.

Tyres and tubeless I’d say, unless you are super skinny and looking for a weight saving from the bike. Rigid forks will be lighter, but you might appreciate a bit of bounce on on the flat cobble sections.

I’ve done the three marked Tour of Flanders loops from Oudenarde on a lightweight road bike, just with slightly heavier wheels and 28mm tubeless at 60psi. Perfectly fine but quite bumpy.

If you go the the Parkwood, consider some barends for varied and potentially slightly more aero positions.

I’m really not worried about the PArkwood in that context, me and it have been very long term friends and i’ve done 2 hours, 4 hours and even 6-8 hour days on it without issue… I’ve done XC rides, sportives and everything inbetween. So comfort and riding position i’m totally good with. If i could increase it’s speed easily though, that could give me a bit ‘more’.

Of course i could just keep the CX bike until March, not use it at all until then and accept a certain level of discomfort on the day… but ideally i’d like to train on the bike i’m going to use for the event.

Can you not just put some big risers on the cross bike?

Failing that, carbon rigid forks and narrow slick tyres.

Why do you need to be “faster” and how much faster would you need to be?

I guess to take advantage of any assistance from drafting etc would be the logical answer to that. In theory i’m stronger on the road that my riding buddy, so him being on a road bike and me on a less appropriate bike should even itself out. But if i can make myself/it a bit faster for a limited outlay, i can’t think of any reason not to do so.

Aero-helmets, rad stickers and long farts

If you’re sure you can’t change your body position, just put the fastest rolling tyres you can find on it. Tubeless Schwalbe Big Ones perhaps? Pumped up to whatever you think your rims will tolerate (45-50psi)
(don’t go tubeless road, the tolerances are much tighter and you don’t want to risk a tyre blowing off the rim.)
You could go aero helmet and stuff, but that would look a bit silly on a flat bar bike. Don’t bother with baggies though.
As people have said, is there anything you can do to adjust the position on the CX bike? Could it be in part getting used to that position, and riding road involving a lot less movement on the bike?

As people have said, is there anything you can do to adjust the position on the CX bike? Could it be in part getting used to that position, and riding road involving a lot less movement on the bike?

Potentially yes…. But whether i’m prepared to put in that level of time, effort and discomfort along with the pain etc, i’m far from convinced.
When actually riding the CX i was getting no discomfort at all.. (Outdoors anyway.)

Indoors on Zwift my shoulders and back of the neck were struggling within about 5 mins.

There’s adjustment within the bike of course, stem spacers, bar/hood angles… but as i say… i’m not feeling a massive desire to throw tonnes of effort at it.

You’re going to be in a much less aerodynamic position.

So just embrace the slowness.

I’d say gearing is a big difference too. I had a mtb that I converted to a commuter bike and later became my zwift bike. fitting a 48t big ring made the biggest difference to my ave speed.

Id get a propper bike fit for the cross bike.

With the best will in the world ‘flat’ bars are not the most comfortable option for long distances. And the usual advice of more sweep and higher bars (or even jones) is not conducive to speed on the road!

And while you can find ways to move arround on them its not the same as being able to alternate tucking down in the drops, cruise on the hoods etc to give your palms a break.

i could just keep the CX bike until March, not use it at all until then and accept a certain level of discomfort on the day

A terrible idea IMHO. There’s no way I would ride I bike at Flanders that I didn’t feel comfortable and confident on. I wouldn’t ride a bike I wasn’t comfortable on at all. I’d either sort it out or sell it on.

But lets not get hung up on that for now, that’s not changing…. the bike is.

I think it’s the key. Changing components won’t make much difference, IMO. Position on a road bike is everything. If you’ve changed it once and it hurt, change it again. Road bike fit is tremendously complicated. I’ve got a set of bars and stems in the garage which I’ve tried in loads of combinations. I’ve settled on a position now which is different from positions I’ve ‘settled’ on in the past. And even when a particular bar/stem combo is fitted there are endless variations besides stem spacers: rotation of bars and position of hoods on the curve are all important. It takes a long time to understand what works for you and what doesn’t. It all changed again when I went to a wider bar – my originals were too narrow.

Fortunately the bargain bin stuff on CRC/PX and even in good road-orientated LBSes on means you can get a bar for a tenner and a stem for a fiver so it’s easy to change. Just get good at wrapping bar tape 🙂

On tarmac, it’s all about reducing aero drag as much as you can, for a level of discomfort you are prepared to tolerate… Turning more of your power output into greater speed.

Clothing
Reducing your frontal area
Aero rim, especially front
Narrow tyre, especially front
Water bottle position
Etc.

If you aren’t used to regular riding road bikes for hours, I’d set up the Merida as relaxed as possible to begin with and with a saddle you know is comfy for multi hour rides. Then very slowly see if you can drop the front end.

I bet there’s a really boring video from GCN on this very topic on youtube somewhere…

Ooh, look, there’s loads
https://www.youtube.com/user/globalcyclingnetwork/search?query=make+bike+faster

Buy some £15 tri bars for your mtb. Job jobbed!

Clothing is a good call. You’ll likely get more speed advantage from wearing a close fitting jersey and shorts than you will from switching around forks or wheels.
A friend of mine did some wind tunnel testing recently and saved 3 Watts by taking his mitts off, so you can imagine what difference a baggy shirt and shorts makes.

Hmmm, the title and the actual question don’t really tally do they?

What makes a bike on the roads ‘fast’ ?

Isn’t really what you’re asking is it, what you really seem to want OP is to make an MTB comfortable/efficient for road riding…

In which case I’d echo others suggestions, ~28c road slicks and maybe bar ends to mix up the hand positions and some rigid forks if you can as lugging about suspension isn’t really going to benefit you…

But honestly I’d look at making changes to the CX bike to improve comfort if you can, it’s already a more efficient road machine by default it clearly just needs adjusting to suit you better. What exactly hurts when out riding? have you considered paying for a professional to do a bike fit?

Have you considered wearing full pro kit?

What exactly hurts when out riding? have you considered paying for a professional to do a bike fit?

When out riding, absolutely nothing hurts, it’s all golden.

It’s indoors and ‘after’ where i’m having issues.

Regarding a bike fit, i’m not sure i see much point, even if i keep the bike for the event, it will be up for sale the week after. This isn’t a long term thing for me, i’m an MTBer. I am doing this as it’s an event / bucket list kinda thing, not because i want to be a Roadie.

Plan is looking like the Rigid forks, carbon jobbies at 500gr instead of 2200gr and a pair of WTB Cross Boss TCS – Light Fast which will save me another 600gr approx. Lastly for that weekend i’ll steal the carbon bars off the T-130 for another 100gr and that’s about it.

We’ve moved on from the CX bike now, it’s already advertised and waiting on a pending offer. (Bit too low for me to accept)

Have you considered wearing full pro kit?

like this 🙂

a pair of WTB Cross Boss TCS – Light Fast

Not an obvious choice if going fast on the road is the requirement.

Not an obvious choice if going fast on the road is the requirement.

Well i wanted something light, these fit that at 400gr each. Something with a bit of flex/give for the Cobbles, which these give and something Tubeless ready, again which these are.

Others on the list are
Continental Speed RIDE Reflex
Panaracer Pasela ProTite Tire

If there’s something else that ticks the above list though, i’m all ears…

Don’t overthink the tyres. My Rocket Ron’s at 40psi don’t slow me down on the road.

If you’re on the MTB I don’t think you’ll keep up with the road trains between the cobbles (should you wish too), whatever you do to the bike. They really shift. On the other hand you may have a modest advantage on the cobbles. I’d be in the ‘make the CX bike fit’ camp – wider bars perhaps, saddle up/down/fore/aft etc.

road trains between the cobbles (should you wish too), whatever you do to the bike

I think that’s going to depend how we look at it… I wouldn’t keep up with a massive percentage of them no matter what bike i’m riding 🙂

On a CX/Road bike with an average ride with some hilly bits in, I can average 17-18mph…. With a bit more flat (like Belgium) i may make it to 19…. but i’m certainly not going to reach 20+ on my own on ANY bike…

13kg Spark 920
2.5 Rocket Ron’s at 40psi
£15 Amazon tri bars
Tight jersey
Aero road helmet
18.5mph for 50 miles.
https://www.strava.com/activities/1908636995

Don’t waste a load of cash fettling. Just ride your bike 😉

Tight jersey
Aero road helmet

Alarm bells there… 😉

When actually riding the CX i was getting no discomfort at all.. (Outdoors anyway.)

Indoors on Zwift my shoulders and back of the neck were struggling within about 5 mins.

I’m not following this. You must be doing something very different on your turbo if it hurts within 5 minutes, but riding outside doesn’t cause any discomfort. If riding outside is OK, why are you concerned about how you feel on the turbo?

Not sure tri bars would be permitted in a sportive, particularly one like Flanders with thousands and thousands of riders on some very narrow, twisty roads.

I remember quite a few local’s on 29ers and fatbikes doing it. There aren’t too many long straight roads where at MTB would be most disadvantaged. You wouldn’t be out of place on the Parkwood.

I have a set of ReneHerse Snoqualmie Pass 44c tyres, picked them up from Sven cycles, earlier this year. They’re silly money but they’re also seriously quick on the road.

You’re also going to need a decent size chainring if you’re running 1x. A 36 tooth at least i would have thought.

The rider makes the bike go fast.

Spend on yourself instead of shiny new kit, a bikefit for the CX bike, a decent physio and a personal trainer, improve your strength and flexibility so you can hold the position on the CX bike.