Cycling UK Forum

Hi All

Looking for some suggestions/guidance on switching the tires on my gravel bike (700c x 38mm Panaracer GravelKing SK tyres) to road tires.
I am looking to do more road cycling this summer so want both options as have already noticed a lot more resistance when out cycling with my friends on 'road' tires.

Would it be better to just change tires when I need to (local bike shop suggested fitting 28mm on existing rims) or better to get another set of wheels with road tires installed? Seems like a faster, albeit more expensive, option.

If the latter, then what are some tips/watch-outs for buying a 2nd set of wheels?
If I go second hand what do I need to look for?
Do I need to get matching disc brakes and rear cassette?
Current bike is Boardman 9.0 ADV.

Thank you!

Unless you want to set up the brakes and gears every time you swap wheels, you need to match exactly the hubs, cassette, and brake discs.

I would only consider a second set of wheels if I was frequently swapping between tyres due to different usage conditions. At the moment I'm changing tyres twice a year because I want the winter tyres to have more grip than the summer tyres. Taking tyres off provides an opportunity to check their condition more thoroughly while proficiency in removing / refitting tyres makes fixing punctures less traumatic.

A more technical reason for considering different wheels is the relationship between inner rim wide and tyre width https://www.cyclinguk.org/article/what- ... it-my-bike. What is the internal width of your current rims? You might also discover that there's a noticeable reduction in comfort as smaller tyres need higher pressures. Perhaps first try a faster tyre such as the Schwalbe G-One Speed in 38mm https://www.merlincycles.com/schwalbe-g ... 29402.html?

Couple of things to consider that I have discovered.
Rim width. It will be irrelevant. Your bike hasn't got anything especially wide so road tyres will be fine. Recommendations by makers are always very conservative and best ignored. 25mm tyres on a 21mm rim is fine but I would be making the most of your space and going for a 30mm ish good quality tyre for the road.
If you change tyres regularly then maybe wheels are best although surely a complete tyre swap is 10 minutes?
I run four disc braked bikes, all nominally CX bikes. I also have eleven pairs of wheels which is fine as they are all bog standard 135mm OLD and QR. Most have tyres and discs mounted but I often keep the cassette with the chain but not always. Some wheels are not the same as others so I have to release then tighten the caliper bolts. Indexing doesn't seem to matter. My best two pairs match because one pair has the disc shimmed to suit the other. Keep an eye on disc wear and pads. If they are really worn and grooved they don't like being mixed up when swapping.
Front wheels virtually always go straight in. If you are running QR hubs then there are stacks out there second hand as people gradually swap to through axled bikes and then sell off their spare wheels. Easiest way is to buy another pair of wheels of a Boardman

Why not just try dropping down a tyre size first? You might find it actually makes little difference to your speed; or on the other hand perhaps it does, and yet it's still wide enough for any gravel riding you want to do. Or buy a road bike for the road?! Could be a lot easier than faffing with wheel changes!

531colin wrote: ↑14 Apr 2023, 3:50pm Unless you want to set up the brakes and gears every time you swap wheels, you need to match exactly the hubs, cassette, and brake discs.

No you don’t. My son is running Fulcrum disc wheels with road tyres on his gravel bike, and also has a set of Vel (Sigma’s own brand) wheels with gravel tyres. He just swaps them over, no adjustment needed.

With tubeless, you don't want to be constantly swapping tyres, but if you're running tubes, it's OK. It all depends how fussy you are - my gravel bike is quite racey but it's a lumbering beast compared to my road bike, even with road tyres fitted. So I'd just get a road bike, but plenty of people do what you're suggesting and like it.

On my Open gravel bike I found that the Rene Herse/Compass Bon Jon Pass (700x35 file tread) were good for both indifferent sealed road surfaces and reasonable quality unsealed roads, plus I had no problems keeping up on group road rides. They get a pretty good rep from both Bicycle Rolling Resistance and road.cc:

https://www.bicyclerollingresistance.co ... -pass-2018
https://road.cc/content/review/254350-c ... extralight

I've run them both as tubeless and with tubes.

The only downside is that they're definitely not cheap, but so long as you don't put a large slash in the casing, they last a long time.

Sven Cycles are the UK distributor: https://www.svencycles.co.uk/rene-herse.

I have two sets of wheels on my gravel bike - both tubeless - with exactly the same hub/cassette etc so they swap over. I’ve a thin pair (43mm) and a wider pair (2.2”) which satisfy all my needs.

1) I was advised not to have two cassettes but to swap the cassette over each time I change the wheels over. Reasoning is that when cassette change required both will have to be replaced. I ignored that advice all worked fine. Now after a short time Im in the position of having to change both cassettes…. ££££££ so I’m learning to swap over…

2) Aparrently you can get spacers etc so that both wheel sets will swap over without needing to adjust brakes.

Personally,a complete pain to change tyres/wheels each time ,especially with disc brakes.I,m a road/offroad biker and have 3 main bikes i.e.dry road bike,wet road bike(with guards)and full susp. off road.For your riding? I would suggest 2 bikes,one for the trails and one for the road.You can pick up decent,used road bikes for not much money,certainly for the cost of a decent wheelset with tyres,3-500 maybe.After a cursory glance on fleabay,I found a Giant Defy, used mainly as a turbo trainer ,£ 299-00.You don,t need disc brakes for the road.

I haven't noticed a huge difference in fit between WTB 650b wheels and Fulcrum 700c wheels. New Tifosi cassette on one, with new centre-lock discs and the original Sunrace cassette with original 6-bolt discs on the other.
Minor rub at the front disc (new pads too) and a minor tweak to the L-screw on the rear mech, but definitely swap-and-go without adjustment necessary if you're happy with 99% quiet

If you're UK-based I'd use the original wheels and swap tyres to a ~32mm tyre, better on our awful roads while retaining a degree of summer off-road ability. The pressure will be lower than 28mm, higher than 38mm while retaining a good rolling resistance. Maybe try Gravel King slick all-road tyres if you get on with the SKs. Too small a tyre and you alter gearing and lower the bottom bracket too much

Swap back to the 38mm SKs when you feel the need to put mudguards on in October/November

wbradley13 wrote: ↑14 Apr 2023, 11:33am I am looking to do more road cycling this summer so want both options as have already noticed a lot more resistance when out cycling with my friends on 'road' tires.

Are you sure your friends are not just a bit faster than you? Tyres do make a difference of course, probably more than anything else, It's still easy to overestimate by how much. Whatever the long term answer (For me it would be another bike) I'd be looking to establish how much difference the tyres would make, before spending any more money than necessary. Cheapest option would be to see if one of your friends would lend you their wheels for a ride or two. Or borrow, maybe buy secondhand, the sort of tyres you're considering, there's a fair range of road tyres now available in 32mm which would probably be my choice, for aesthetics as much as anything, put 28's in a frame designed for 40's is going to look like you've done just that, very gappy. I certainly wouldn't be buying new wheels unless I was sure they'd make a significant enough difference to warrant the hassle.
I have run a bike with two sets of wheels, didn't work for me, maybe I'm too lazy, the bike mostly got used with the wheels whose tyres would do anything. I ended up with another bike, but at least I already had the wheels!

My experience is that gravel tyres, not exactly the same ones as the OP, but very similar in terms of knobble-size and general suppleness, do make a very significant difference on road, specifically on steep climbs.

Rolling resistance figures as measured on drum-rollers seem to be only half the story, in that it is when climbing steep hills on tarmac that the gravel tyres become really “boggy”, and I’m convinced it’s because the tyre deforms along the axis of roll when high torque is applied, as well as doing the usual and deforming under vertical load.

This deforming is what gives a super-supple tyre super-grip powers off-road, and it doesn’t add noticeably to drag off-road, but it becomes a really noticeable penalty where the surface is hard and smooth, and super-grip isn’t needed to maintain traction.

To give an idea, the gravel tyres give worse drag up steep hills than the same size Schwalbe Marathon Plus, both being set to recommended pressure, which as many will know are effort-sucker tyres. On the flat and downhill, no issue, but like glue uphill.

I don’t have two sets of wheels, or a specifically road bike, and I very rarely ride with a road group, so I’m “just putting up with it”, but am on the lookout for a slightly better road/off compromise tyre. The new Schwalbe G-one Overland might be worth a try.

If I was regularly riding with a road group, I would want two bikes, or two sets of wheels, and I think the former might be simpler.

PH wrote: ↑15 Apr 2023, 9:44am

wbradley13 wrote: ↑14 Apr 2023, 11:33am I am looking to do more road cycling this summer so want both options as have already noticed a lot more resistance when out cycling with my friends on 'road' tires.

Are you sure your friends are not just a bit faster than you? Tyres do make a difference of course, probably more than anything else, It's still easy to overestimate by how much.

I've run my CX/gravel bike with road tyres a couple of times and it'll never be as fast as a proper road bike. It weighs more, the position is not as aero and the gearing is substantially lower.

Changing tyres is fine the first couple of times you do it and then it becomes a massive pain. If you're running tubeless, it's just always a massive pain - in fact I would specifically say NOT to use tubeless if you are changing tyres regularly.

For me it would depend what riding you're doing and how often - if you're doing (say) a roadie club ride on Sunday and then solo mixed road/gravel the rest of the time, frankly I'd not bother with changing tyres for one ride, I'd put up with being a bit slower - sometimes you can negate some of the speed loss by pumping the tyres up a bit harder for a pure road ride.

The obvious answer is a road bike and a CX bike of course.
The next best solution is a second set of wheels but I'd be surprised i it was significantly faster - the gearing and the position plays a major part in it too and even if you fit a road cassette, the top end gear is not going to be much different to what you have now, there'll just be closer gaps between the ratios.

I have a road set and gravel set. Both 10s. Different hubs. Takes a bit of faff with the initial set up getting just right. Disc shims and cassette spacing. But easy once it's done..

I use QR reckon it would be easier with a TA...