I've created a dilemma for myself by building my first gravel bike out of a CX racing frame (steep angles, high BB) and falling in love with the fast handling and nimble climbing.
My new gravel bike is slightly more stretched and lazy but makes up for it by feeling faster in general on the descents, it really wants to just open up over the rough stuff and I want to let it, but my poor tyres and rims are suffering for it!
Am going to experiment with inserts over the summer but have spotted some very nice new forks which would allow me to run 700x45 front and rear, more cush, more protection, fewer damaged tyres.
Am just worried about handling etc. I've only just re-fitted the 700x40mm tyres after a winter on CX tyres and the handling feels odd, almost a bit of self-steer, although I don't know if new inserts are affecting that.
Has anyone gone from 40mm to 45mm and noticed a big difference in handling?
Has anyone gone from 40mm to 45mm and noticed a big difference in handling?
I haven't tried it, but tyres are manufactured to a +/- 3mm tolerance so there might be no size difference unless you're using the same make/model
Narrow rims (31mm? to 45mm tyre), tread pattern and pressure are more likely to be factors IMHO. Tread outside the casing width isn't measured, e.g. shoulder knobs
Well I was considering just upsizing my Terreno Dries, they're now available 700x47 so will be bigger than the equivalent 700x40 to some degree.
Alternatively the Pirelli Cinturato Gravel RC which looks like most of the best bits of the Terreno but with some more grip between the flat centre tread and the edge tread, something I've sometimes wished for with the Terrenos 🙄
Strangely I do have experience of Terreno Dry 31mm and they measure 35mm on a 22mm internal rim. Might be worth a measure first 🙂
WAM and RAM is a Vittoria thing too https://www.vittoria.com/ww/en/stories/tech/wam-ram
Never tried inserts, but self steer is very often a product of low pressures. What pressure are you running?
For me the bigger question is nobbles! I have had a cross bike for the last 17 years that was arguably a forerunner of a gravel bike - the On One Ti Cross. I've now got a new proper gravel bike on order (one of the Ragley Trigs from the recent PSA). It comes with 47mm WTB Senderos - quite knobbly numbers and I'm very much setting up for off road. It will be interesting to see how my attitude to a bike that is much more capable off road but draggy on the road suits me.
I'm riding 45c WTB Raddlers and absolutely love them. Nice and fast, good grip everywhere really.
They only measure about 40mm on my calipers, mind.
Love a Terreno Dry 👍
I’m an habitual tyre changer and have gone up and down in the sizes you are talking about. I noticed a marginal change in how the bike felt starting off when I changed; it felt spritelier with a smaller size (700/38 & 40) and marginally less so with a larger (700/48) size.
What was definitely noticeable and (unsurprising) an improvement was the bump absorption with the larger size.
I use(d) inserts on my cyclocross race bike and they help but are a bit of a faff, and is not rush to use them again.
If you can go bigger then do it. Steering flop hasn’t been an issue for me.
I use(d) inserts on my cyclocross race bike and they help but are a bit of a faff, and is not rush to use them again.
Yeah, that's what started me thinking, installing some new Vittoria Airliners was a bit traumatic, initially had me thinking about a second set of wheels rather than having to swap tyres for conditions!
Cheaper and more sensible option is just to make peace with the 29er and get used to flat bars again, it's a very fast bike and better suited to the fast chunky stuff that I'm currently dinging rims and pinching tyres on. Just not so much fun on the fast/flat/tarmac connectors... 🙄
Coincidentally, I've just changed wheels on my Amazon - from a 650x47 setup to a 700x40 - and can definitely feel the bike to be lazier in the twisty stuff. It needs earlier, and more, steering input. I wonder if you might notice a bit of the same as the bigger tyres add more weight?
That's interesting, I would have thought the 700x40s would have felt quicker!
Obviously more a function of diameter than width then...
I'm having a similar debate with my CX/gravel bike - it's currently got 38c Schwalbe G-One on there, a Bite on the front and an Allround on the rear so I'm looking for something in that sort of width but a lot of tyres have gone up to 40/42+ in the last year or so.
Mine does about 50:50 road/gravel so I don't want to go too big and compromise the on-road ability. Will keep an eye on this thread though, it might help my decision!
I’m with Scotroutes 47mm on 650c steers faster than 40mm 700c
I think that’s because the smaller wheel has less trail. So not quite your situation
It’s not as cheap as a tyre swap but I think you’d like 650b with big tyres. It would drop your bottom bracket a touch too
Once I’m off road I’m always happier on the fatter tyres. I currently have Sendero on but for what I’m doing at the moment I’d be better of with the Terrano Dries. These are at least 50mm and visibly bigger than the Teravail Rutlands in the same stated size
NB I don’t feel the need for inserts so let’s assume I’m pushing less hard than you
NB I don’t feel the need for inserts so let’s assume I’m pushing less hard than you
To be honest I've gone from almost two years of happily using tubes trouble free, to now 'needing' tubeless with inserts 🙄 I've suffered the same sort of puncture three times now (pinch flatting a tyre which then won't seal) and have dinged rims quite badly (only once, and strangely without puncturing that time).
Don't know if I'm just getting more confident and exceeding my own abilities and smashing things, or maybe I've just been unlucky once too often.
I’ve suffered the same sort of puncture three times now (pinch flatting a tyre which then won’t seal) and have dinged rims quite badly (only once, and strangely without puncturing that time).
So what pressures are you using?
40psi @ approx 88kg rider weight
To be honest I settled on 40psi as being the ideal pressure back when I was 85kg 🙄
Last 'pinch flat' was possibly due to under-inflation of a 35mm CX tyre as I haven't settled on an ideal pressure for these, might only have been 45psi.
In your 40mm rims? Assuming all is as you think (the tyres are genuinely 40mm and the pump gauge is accurate) I'd say that's low but not stupid low. I'm roughly the same weight as you and I'd probably only go that low if I was on pretty smooth loamy terrain and I'm pretty light on my kit. If it was a bit more rocky or I was night riding and more likely to plough into potholes or square edged obstacles, I'd be going up a bit, just to save the rim (or prevent burping).
40psi in 40mm tyres on 19mm rims, yeah.
I'll try 40psi for now but with the inserts, ideally I would try 45psi without inserts first but they're already installed and I don't want to go anywhere near a tyre lever again for a wee while! I guess I won't know for a few months and some rocky descents if it's suitable as good old chance might dictate I wouldn't have punctured anyway!
The bigger tyres would be an expensive experiment as it would need the new forks so I should probably experiment for another summer before taking the plunge. Perhaps I've just always been pushing my luck with pressures and not realising it.
In the last couple of months I have gone for a set of Gravel Kings in 43,they can ambush you a bit in the slick stuff,but once I adapted,I found them (for my riding) to be excellent in mixed surfaces. They are also not too draggy on tarmac if you whack the psi up.
I run 700x40s at about 40psi. The 650x47s have been as low as 18psi. No pinch flats (yet!). I don't show any particular finesse in my riding either 😂
Over the last 2-3 years I've gradually upgraded from 35 to 40 & then on to 45mm G-One All Rounds. Riding is 50/50 gravely towpaths & tarmac. Other than the drag, everything else has been worth it, comfort & puncture resistance. They can be a bit weird at first for on road handling, e.g. downhill cornering on stuff steeper than 15% but otherwise, i don't see myself going back.
