I’m specifically thinking 650×47 Byways vs 700×38 g-one allround. I know it’s a long shot, but I wondered if anyone had ridden both (or something similar) on a gravel-type bike and could comment on the relative performance on and off road

Depends, innit.

Personally, I use mine for a mix of road and off-road and I’d always go for the 700×38 because I find the handling just feels different with wider tyres, in a way that I happen not to like (YMMV). But if I was predominantly off-road then I’d probably go for the fatter option (but with some knobs; I’ve just built one up with 27.5×2.2 Bee Lines although I’ve not used it yet).

I tend to find that the benefit of running wider tyres is being able to run them softer to work better off-road, but on the road that softness just means drag. 35-38mm seems to be the dual-use sweet spot for me. But, again, YMMV: your gravel-to-tarmac ratio may be different.

Have used both.
The 650 were a bit comfier feeling on off road and rubbish road surfaces. Maybe a little slower from an average speed point of view but only by 1-2mph.

I’ve got some 700 x 45 WTB Riddlers – I prefer the bigger diameter simply for the way they roll over lumpy bits better

I have a gravel bike and run a couple of sets of wheels.
I have some 650b that currently have WTB hiway 47 and panaracer gravel king 43mm in 700c.
The 650b is smaller radius which lowers the bb and the gearing, but is teally nice in the dry or damp slate quarries here in Snowdonia. If uts more offroad and likely to be wet and muddy then i run the gravelkings or if its slop i run some 38mm 700c vittoria terreno wets. All are ace.

Thanks. My Kona came with the Byways. They are wonderfully comfortable, roll pretty well and I love the way I can smash them through quite rough sections without worrying about flats. But my riding is probably 80% road with 20% forest and farm tracks. Maybe a bit higher on some rides, but if a ride was mainly off-road I’d almost always take the MTB.

I’d agree the Byways probably only lose 1-2mph over a road tyre, but dropping the average on a hilly road ride from 16mph to 14mph is quite significant.

The Byways, with their smooth centre also have very little traction when it’s even slightly damp off road. I’ve failed to get up a few climbs that I’m sure I could make with just a bit of tread.

So, I’m thinking 700×38 allrounds might be just as fast on the road as the Byways while giving a bit more climbing traction off road. But that sounds too good to be true and it’s not a cheap change.

I live in east Dorset. The riding here varies between Forests, Heaths, sandy tracks, rocky Purbecks and mtb type single track
I ride my gravel bike primarily off-road. Road is used to join up the bits.
I’ve used both tyres.
The 38 Allround is my go to summer tyre. I find them quick on most surfaces and have a surprising amount of grip. They come off around October when they begin to slide out when pushed out in wetter conditions. I really like them. They bang up tubeless really easily and don’t appear to loose pressure over time.
The Byways were put on by my LBS when the bike was built up as they are big fans of wider 650b tyres for general “gravel” use. They performed well in all conditions but I always felt they seemed a bit sluggish in use. This was almost certainly due to my lack of cycling strength. One of the LBS owners uses Byways on his gravel bike when he leads the local (quick) road rides. They definitely have a more comfortable ride, especially when run at <30lbs which I did. I took them off simply because I was looking for some “free” speed to keep up with group rides. The Allrounds are quicker, but probably not much. I wouldn’t use Byways in the winter.
You won’t be disappointed with either and if you are a better rider than me then the Byways will be fine. Here’s a link to a Byway review.

Review: WTB Byway Road Plus 650b Tubeless Ready Tires

700s.

650s don’t roll as well, feel heavier and offer very little benefit over the 700s, IME.

As dovebiker says, if you need bigger tyres just go 700×45

^^^ Yep, this.

Not always possible to do this. I can’t remember the exact sizes but on my Diverge the fattest tyres that will fit the width clearance need to use a 650b wheel so that there is sufficient height to allow clearance on that axis too.

I’m keen to try some 650 wheels on my Topstone, just waiting on some bargain rims as i have spare hubs, lockdown job…

Iwould suggest Gravelking SK in 38 x 700. My riding sounds similar to yours, all the gravel around here is fairly easy going and I do a lot of road miles in between. The SKs roll really well on the road, don’t wear too quick and have a surprising amount of grip. They also do a 43mm, which I’m tempted by for the front.

if you need bigger tyres just go 700×45

I’m actually thinking more the other way. If I went for the basic Hunt 4-season gravel wheels with the 20mm id (rather than the more expensive wider versions) I’m thinking that would work ok with the 38mm g-one allrounds and also give me the option of going for something like a 30mm g-one speed if I wanted to do a long ride that was 90-95% road.

GravelKing SK works be another alternative and seem pretty similar to the g-one allround.

I have tried the Schwalbe and not the byway but exposure which are very similar (almost exactly)

The g-ones are super fast on road but I found them very squirmy in the corners off road if they weren’t inflated to rock hard pressures.

The exposure/byways are also fast (being a semi slick) but the extra cush from the bigger casing is great offroad.

If I was racing it would be 700c all day long. If speed isn’t important then 650b. Both tyres you are looking at are dry conditions only. So expect to swap for the winter if you are still venturing off the tarmac.

I’m a fan of the Byways but I also have a set of wheels with 700×40 Nanos. They are noticeably faster if at a higher pressure, but that eats into comfort.

A larger 700c tyre won’t fit so thats not an option for me.

I’m interested in any feedback you have on the Allrounds.

650b byways for dry weather, but I agree any wetness and they’re useless!

They’re great on tarmac, I tend to run them at 30-35psi if I’m doing mostly tarmac, and 25-30psi off road.

When winter arrives its a pair of wtb senderos that get fitted, again 650×47.

Having tried a 650b gravel bike and owning a birk with 700×42 – if you feel you need anything chunkier than the 700c wheels, then your on the wrong bike and would be better off with a light/fast/rigid flat bar mtb of some sort.

Both ‘gravel’ bikes I’ve owned have been 650b and for me it suits the riding I do. There is more to the set up than just the wheel size/tyres that make a difference to the on road pace (IME based on the 2 bikes I’m talking about)

I did have G One speeds for a while but went to back to Byways as I found that I couldn’t take the ease that G Ones picked up glass and punctured. Also found on loose climbs the Byway was quicker to regain traction.

@RP I know you enjoy a read so I’ll share an article or 2 that you might enjoy.

As promised

Comfort test part 1

Comfort test part 2

650b v 700c

My preference is for 700×40-45s. The 38s just feel too narrow, even on gravel roads (and despite it being theoretically only 2mm it’s a suprisingly noticeable difference in terms of control). I started out on 35s and they were really sketchy.

My gravel riding varies from fast gravel rides for training (17-18mph stuff) and what are basically gentle MTB rides and I’m very happy with 40s and wouldn’t want anything narrower for a one tyre fits all set up.

if you feel you need anything chunkier than the 700c wheels, then your on the wrong bike

I strongly disagree. My 650x50c are as fast as my mates 700×35 on the road, so no real penalty there. But offroad I can slay him on anything pointing downhill. It makes the bike really playful and fun. Agreed a MTB would also be fun offroad, but even the fastest mtb is a drag on tarmac.

I built a gravel bike up recently with 650 b and it worked well enough but switched over to 700. They feel a bit quicker on road and flat tracks. Not so much pedal input perhaps. Off road the 650b looked tiny but I’ve been on 29ers for a decade so probably just what I’m used to.
Had G big ones on a monstercrosser previously and they always seemed fragile so I would go easy on them
Now run gravel king SK which seem better for a bit of general on and off road

Thanks for all the reading @NM Lots of interesting stuff in there, although it would suggest I could stick with 650b just as I’d made up my mind to try 700c 🙂

650×47 Byways vs 700×38 g-one allround. .. relative performance on and off road

The G-Ones will prob roll easier on road, they’re lighter tyres and more supple. eg, G-One Speeds 50mms do roll a bit easier than Horizons and Byways ime. Can’t imagine the Allrounds being much slower than the Speeds.
Off-road, ime/imo between big 650s and middling 700s, big 650s handle loaded riding and impacts better due to the added volume. If you went for 700×50 you’d get the volume as well as the added roll-over. 700×45 vs 650×50, tough call. I prefer the volume the bigger 650 has as the Riddler 45mm casing is smaller than a Byway 47mm by more than the designated size suggests, but the bigger OD of the 700×45 starts to be felt. On tarmac I’m equally happy on either size. Makes little odds.

For 700 to feel notably quicker than a big 650 on road (feel, rather than to actually be) I’d be down to a 35-38 and then the volume is just a bit small for off-road use, personally. I’ve ridden a lot of byway miles on 700x35s in the past quite happily but now 40-45s and bigger 650s are available it’s clear how limiting they always were.

The biggest advantage for 700C gravel bikes is being able to pop a 28 or 32 on there and go for a fast road ride. A 650B bike can be a quick road bike over a distance but lacks the snappy, quick-response feel. Great off-road though. I’ve settled on 650B for my mixed terrain and loaded touring bike and a proper 700 skinny bike for road miles.

I’m running the OEM 700c x 40 Giant Crosscut Gravel 1 on my Revolt and they are fine. Enough volume to provide some cushioning on trails, enough grip for most of the slippery stuff I have tried and fast enough on the road if pumped up a bit.
When they wear out I will be looking for replacements in the same size as they suit my riding.

Thanks for all the comments. I was going round in circles so went out for my daily sanctioned ride. Of course, the trails are drying out nicely now. So, having struggled all winter with the Byways, they are just coming into their own now. Bombing down a rocky, sandy track they felt amazing.

I think @jameso (along with some of the articles @NM posted) hits the nail on the head. The main advantage of 700c (for me) would be that it would give me the option of running 30mm tyres and turning my gravel bike into an endurance road bike. But, why am I thinking of doing longer road rides again, after all these years when my road bike has sat, unloved, in the shed? I suspect it has a lot to do with the smooth rolling comfort of the those Byways. Maybe I’d feel a lot less keen if I went back to narrower 700c tyres.

I still might give it a go, just to scratch the itch, but maybe I’d be better off sorting out the gearing first, so that I can stay seated for a bit longer on the climbs

Second wheelset then?

Yes, it’s the only answer really 🙂

Of course, the trails are drying out nicely now. So, having struggled all winter with the Byways, they are just coming into their own now. Bombing down a rocky, sandy track they felt amazing.

There’s no way I could have stayed on byways over winter, gimme some knobs and some actual grip!

47mm senderos in the winter we’ve had.

And you know what, for the bit of road I do, they haven’t been anywhere near as slow as I thought they’d be. I’ve even done 40km road rides on them with an average speed of 13mph.

But, why am I thinking of doing longer road rides again, after all these years when my road bike has sat, unloved, in the shed? I suspect it has a lot to do with the smooth rolling comfort of the those Byways. Maybe I’d feel a lot less keen if I went back to narrower 700c tyres.

If you want a good road feel and your bike has a not-too-low BB, try something like 650B Panaracer Pari-Moto 42s. The 2 fastest times I’ve done on a 95 mile route I’ve ridden many times on a number of different bikes was on a light road disc bike that had 19mm rims and Pari-Motos on. Bad science I know, conditions & form vary, but that bike was both comfortable and efficient in a way that blended the best of my current road and all-road bikes. Was a bit too niche to be a mainstream bike model and the tyres flatted too often for my liking (can get TLR versions now though) but it says that the BQ randonneur types are onto something.

I’ve used G-One Speed in 700×38 but not the tubeless ones – found them pretty good as long it was dry.

Currently using WTB Venture 47 on 650 wheels. Much prefer them and the smaller wheels for all round gravel. The Ventures have tread and therefore I would imagine offer more grip than the Byways in damp conditions and I’ve not had any issues, but, like a lot of tyres are rubbish in proper mud. But I don’t tend to ride through proper mud that much.

My caveat though, used the different tyres on different bikes – G-ones on farily heavy Boradman ADV8.9 and the Ventures on much lighter Vitus Substance with carbon wheels.

For anything with off-road sections much prefer the smaller wheels – more nimble, quick acceleration etc. Also my times are the same if not quicker on road sections than on the G-ones, but obviously a lighter bike. Slower than road bike though.

Like Jameso, I’ve settled on 650B for gravel and a separate dedicated road bike.

My original plan was to get a second set of 700c wheels, but don’t really see the need now.

Thanks. I hadn’t seen the Pari Motos before, so that would be an option if I did want to do a long road ride again I guess.

I do like the feel of the smaller wheels and think they suit the longer wheelbase and slightly slacker head angle quite well. The extra width is also great for blasting through the rougher bits.

I’ve ridden the Byways in all sorts of inappropriate conditions and (just about) managed to stay rubber side down, so it would be a bit daft to ditch them just as they are coming into their own.

🙂

I’ll probably take off the senderos and put my byways back on fairly soon if it stays like this, the trails that 2 months ago were a boggy mess are now hardpack dirt.