After over 30 years of road riding I've spent the past 5 years riding almost exclusively off road and on the rare occasions where I've been on tarmac it has been on an MTB. However, I've now done a couple of road rides on my old (2003) Principa Rex eSx road bike and it's funny the things that now seem strange:
Positives
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Effortless speed: I'd forgotten how easy it is to cruise along at 15-20 mph on a road. Throw in a tailwind and it feels like you're flying without trying.
Smooth: This was a bit of a shock. Switching from a full-suss MTB with 2.4" tyres at 20-25 psi to a stiff fully rigid "race" bike with 23mm tyres at 90-100 psi I really expected the ride to feel much harsher. In fact the opposite was true. Even on our crappy B-roads it just felt so smooth. Well, right up to the point where I tried to take it down a farm track anyway 🙂
Easy to take it easy: Riding off road (at least up here in Scotland) I'm usually either breathing out of my ears trying to get up some climb or my heart is pounding as I try to get down the other side without dying. On the road I found I could just ride the climbs and flats at tempo if I wanted and actually have a rest on the descents, which meant I finished a two hour session feeling nicely tired rather than wrecked.
Much less faff: Tube/tools/CO2 in a small saddle bag, water bottle on the bike, phone, snacks and a waterproof in a jersey pocket, straight out the door and away you go.
Negatives
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Cornering without a dropper: It just feels so much less secure trying to go round a corner when you can't drop your CoG. I'm starting to get used to it again but I'm sure I could go a bit faster and be safer if I could just get a bit lower.
A 39-53 chainset with a 12-25 cassette doesn't give as many hill climbing gears as you might like. I need to re-learn how to ride out of the saddle for an extended period.
New aches and pains: Narrow low bars means pains in my neck and shoulders that I'd forgotten about. I'm also getting a pain in those big tendons at the back of the knee after a few hours. I think I've got used to just plonking my flat shoes on the pedals at a natural angle and the combination of clipless pedals and a narrower Q factor is causing issues at the moment. Both are probably just a matter of conditioning though.
Finally, head winds suck and cars are annoying.
Take up running next then you realise how restricting having a bike is
Cornering without a dropper: It just feels so much less secure trying to go round a corner when you can’t drop your CoG. I’m starting to get used to it again but I’m sure I could go a bit faster and be safer if I could just get a bit lower.
Sounds like a possible bike set-up issue. Might wanna lower the stem and see if it clicks as you get more front-end grip.
A 39-53 chainset with a 12-25 cassette doesn’t give as many hill climbing gears
I'm on a compact chainset (50/36 IRC) and 11-32t cassette for the Lancs hills. Would recommend.
Ive just come back from a few days road riding in the Alps. No pot holes and no cars trying to kill me.
Took my MTB out for a spin on Sunday and it was a shock. Wet roots, suicidal squirrles all added to the excitement.
Road bike will not go in the loft and Im quite looking forward to slippery night rides.
I think its good to swop around, you then realise whats good and what you miss.
@FunkyDunc: Cycling = exercise + shiny toys. Take away the toys and it's just exercise 🙂
@chakaping: Good points. I did flip the stem to raise the bars a bit as it turns out I'm not as flexible as I was five years ago. Something else to work on. If I do end up doing more road riding (and only time will tell on that one) I may treat the bike to a new compact chainset and cassette. That's if I can resist the urge to buy a new bike of course 🙂
Off road I ride a rigid 26er single speed, a 27.5 carbon hardtail, or a 140mm 29er FS. On road I ride a Brompton or a carbon road bike with di2. It's certainly true that the road bike is really easy to go relatively fast on, but what I love is that they are all totally different experiences, so I'm never likely to get bored, I'll just ride a different bike. I'm also really thankful that I'm in a position to have these choices. Basically, bikes are great.
When I ride my gravel bike it's definitely more of a sustained, but lower effort than on the mtb which is much more 'peaky' - its improved my fitness loads too.
Also, squirrels. Is there something going on with them at the moment? Every day I get one run out in front of my car or bike, and there's a local one here which I'm sure is a bit... 'special' 🤣
I'll be doing something in the drive and it'll come belting round the house, spot me and then belt back the way it came... 😁
Smooth: This was a bit of a shock. Switching from a full-suss MTB with 2.4″ tyres at 20-25 psi to a stiff fully rigid “race” bike with 23mm tyres at 90-100 psi I really expected the ride to feel much harsher. In fact the opposite was true. Even on our crappy B-roads it just felt so smooth. Well, right up to the point where I tried to take it down a farm track anyway
Very old school road bike set up there. It's now 28mm at 60psi or lower, or 25mm if you're frame won't take anything wider.
Good podcast on the latest thinking on road bike tyres.
As a returning roadie, I listened to that a few weeks back and have since been experimenting with wider and lower pressure tyres, and am now pretty much converted. Not touched my roadbike with a pump for weeks, whereas I used to religiously put 120psi in before each ride. Now, if it's now flat, that's good enough and off I ride.
Thanks. Yes, I have been checking clearances to see if I could run anything wider. I think it's a bit tight for 28mm and my nice Mavic Ksyrium wheels are probably a bit narrow too, but 25mm might fit. Just not sure if I'd notice the change from 23 to 25mm.
Yes you would, it's quite a big difference.
25s are fine on ksyriums IMO
Ok, thanks.
I picked up some Conti GP 4000 IIs in 25mm and 28mm relatively cheaply. As the 5000 has been released, lots of places discounting the old 4000s.
Take up running next then you realise how restricting having a
bike isn injury is
OK, I've listened to that podcast. Fit the best tyres you can afford in the widest size that will fit your frame. That seems to be the take home message.
OK then, let's take that to its (illogical) conclusion. I've got a fatbike frame sitting in the shed doing nothing. It's nice and light (Carbon), stiff etc. I could stick on some flat bars and bar ends (oh the horror) to give a decent position on the road and basically fit any tyre width you like from super narrow road tyres up to 5" monsters (with varying rim diameters and widths to suit).
Does anybody think it would be possible to build this up so that it is faster on the road than my "proper" road bike (with 23mm GP4000 tyres)? To make life a bit easier let's say faster up a road climb, so that aero effects aren't too large. If so, what tyres would you go for? Extra points for an actual tyre (brand/model) rather than just a size and double bonus points if you show your working 🙂
The amicable roadie-retro-dork Jan Heine has done a lot of testing of the common (or uncommon) road sizes - ie 700c and 650b with slick or near slick treads - if I recall he does it on a roll down test on a gentle slope to flat on tarmac, seeing what tyre (as part of a bike and rider system) rolls furthest.
The issue with what you ask (up a road climb) is you are adding an acceleration. Unless you have the perfect pedal stroke of a 24hr track cyclist, your stoke is going to have peaks and troughs of power. up a hill, when your power drops, so does your speed. (Yes on the flat too, but not as much). Slowing down and speeding up twice per crank revolution means that the inertia of the wheel/tyre comes into play. *
There's no way you're making a 50mm tyre the same weight as a 23mm for similar rubber compounds and a practical thickness, so fatter tyre means more inertia. Now as inertia is greatly affected by distance form centre of rotation, shrinking the wheel can counter this. This has been claimed for years - that a fat (in road terms) accelerates like a skinny 700.
* to come back to this, in some ways this inertia is beneficial - as it will help to smooth out the unevenness of your pedalling, acting as a flywheel. The resistance you are facing - basically the gradient you are climbing, so this will vary throughout a ride - will alter the point where this is helpful or not.
tl;dr It depends. Skinnier does not automatically equal faster. but we knew this from fatbikes anyway.
up a hill, when your power drops, so does your speed.
Edited because I then read the (*) note.
I could stick on some flat bars and bar ends (oh the horror) to give a decent position on the road and basically fit any tyre width you like from super narrow road tyres up to 5″ monsters (with varying rim diameters and widths to suit).
The problem you have with very wide tyres is they don't have super flexible side walls. If you listen to the podcast what you are trying to do is minimise the total combined energy lost by
1) vibrating the bike and rider from imperfections in the road surface
2) side wall of the tyre absorbing energy flexing
So, with fat bike tyres you'll be limited by 2). With road tyres if you pump them up to 160psi you minimise 2 but maximise 1. As you lower the pressure you reduce 1 but marginally increase 2. If you have decent soft side walled tyres, the increase in 2 will be less than the reduction in 1, so your overall losses are reduced.
Slowing down and speeding up twice per crank revolution means that the inertia of the wheel/tyre comes into play. *
Aren't you forgetting the inertia of an 80kg rider plus 10kg bike travelling at 20mph? That will far outweigh the inertia of the 1500g wheel set rotating below them. Spin a bike up on rollers to full sprint pace then bunny hop off, you'll pretty much stop dead (you don't have enough inertia to move forwards). Sprint full whack on a road into a brick wall, you will definitely feel the effect of all that inertia of the rider plus bike going 30mph to zero....
So that’s what Froome was trying to prove them 🙂
I wasn’t really suggesting that 5” tyres would be fastest, just that I could go that wide in theory. The Jan Heine site does make fascinating reading (thanks) but he does say things like wider is better when the tests only compared, say, 23, 25 and 28 so don’t really prove that 50 is just as fast. It’s also clouded a bit by the fact that they want to sell you their tyres. Still interesting though.
Inertia is a good point. In general I find that I don’t mind a bit more inertia. Harder to accelerate, yes, but also slower to decelerate and I quite like the feel (powering over rollers etc). Probably all those years on mountain (and fat) bikes. Weight must play a part as well of course (at least on climbs) but tyres are mostly air and there are bigger differences between makes than there are between sizes, within reason.
Aren’t you forgetting the inertia of an 80kg rider plus 10kg bike travelling at 20mph? That will far outweigh the inertia of the 1500g wheel set rotating below them. Spin a bike up on rollers to full sprint pace then bunny hop off, you’ll pretty much stop dead (you don’t have enough inertia to move forwards). Sprint full whack on a road into a brick wall, you will definitely feel the effect of all that inertia of the rider plus bike going 30mph to zero….
I did mean when going uphill, which I was picturing as about the steepest you could climb seated at a reasonable cadence, with a normal road compact.
90kg Barrelling along on the flat or near flat at 20mph then I agree, even the choppiest pedal mashing isn't going to slow you noticeably between pedal dead spots
To make life a bit easier let’s say faster up a road climb, so that aero effects aren’t too large. If so, what tyres would you go for? Extra points for an actual tyre (brand/model) rather than just a size and double bonus points if you show your working
Up a climb the weight of the tyre is more important so the weight/rolling resistance ratio differs. And also depends what type of climb and what the surface is like. If the surface is very smooth then a wider tyre will not bring as much benefit as if it were rough i.e. if you rode up a hill or anywhere else) that has a glass like smooth surface the narrower and lighter the tyre the better.