New wheels+tires or NOT

Hi,

I have a gravel bike and have been wanting to get road wheelset to be a bit faster on the road. I got the money but now I am having second thoughts as I don't know how faster I would be?
Right now I have WTB isym 23 wheels (with cheap formula hubs) with WTB 650x47 Horizon tires. The tires are more road+ tires than gravel tires and are smooth on the center with no knobs. I was thinking of getting 700c wheels with road 700x32 tires (for some comfort on day long rides and some light gravel).
I do not race, and I am still working on my fitness (as my work and family time allows). My average watts (according to Strava) is 210W for an 1h ride and some 180W for an 3h ride after which I feel pretty tired (although not totally exhausted).
With new wheels and tires I could loose some 500-600g of weight and should have better aerodynamics and lower rolling resistance.
My question is will all those 3 things make a significant difference? Only one of those would probably not, but with 3 combined will it make a difference?

Thanks.

Comments

  • joe_totale-2
    joe_totale-2 Posts: 1,333
    The tyres will make a bigger difference IMO than a wheel change but if you've got the cash then I'd get both new wheels and tyres.
    I've personally found that 28mm tyres provide more than enough cushioning on the road and are faster than 32mm ones, I accept though that they'd not be so great at the light gravel. If you were mainly going to stay on the road I'd consider them.
  • singleton
    singleton Posts: 2,495
    I'd say be honest with yourself about what you want.
    I've got a Cyclo-cross bike with 2 sets of wheels. The offload wheels with suitable 38mm tyres and some road set with 28mm road tyres.
    I have the road wheels for winter club runs where I just would not be able to keep up with 38mm off road tyres.
  • spirox
    spirox Posts: 7
    @joe_totale-2
    I can not change just the tires (at least not these) as I have 650b wheelset and would go to a 700c. I could put 650b x 32 but that would lower my BB quite a lot, and might be too low.

    @singleton
    I also might keep existing wheelset if I see that I would like to do more gravel. But then those would be strictly gravel tires with more knobs, and 700c wheelset would be for road tires.
  • spirox
    spirox Posts: 7
    OK, I managed to borrow some wheels to put on my bike and do a direct comparison.
    Couple of things to notice:
    - The wheels are almost the same as the ones I was looking at. The difference is in the hub and the tires. They are not dt Swiss hubs and the tires are some Specialized turbo pro 28mm road tires that came with the friends Roubaix.
    - I wasn't my top when I did this, I might be coming with a cold.
    - I had head wind about 1/3 of the way up because why not! It wasn't very strong but I could feel it slowing me.
    - I don't have a power meter so I rode against my heart rate. If it would go below 168 I would accelerate and if it went higher decelerate. Not the best way but that's what I did when I did a PR on this uphill.
    - Tires were at 80-85psi or around 6bar. Not tubeless.

    And the results? My time on an 5% ~8.5km uphill was exactly the same at 37min! (give or take a few seconds) as with 650b 47 tires. I was very surprised!

    Observations :
    - The bike felt very different, it felt quicker and more maneuverable.
    - It actually didn't feel more uncomfortable, in fact the road felt smoother! The potholes and speed bumps though were a lot more noticeable.
    - Braking is noticeably worse. I had to brake sooner on downhill.
    - When going back down I did a PR without even trying. That was VERY surprising as I didn't even pedal all the time. It might have had something to do with wind as on downhill it was in my back.

    Conclusion:
    With these wheels/tires I am probably a bit faster. I would say 3-5% judging by the headwind and the fact that I didn't feel my best. I definitely like the feel of them, but will I buy them? Actually I found those same wheels for 200€ with rotors which is a great deal so I will buy them Although I am not that faster they do feel better on the road and when I'm fully recovered if I can be 5% faster on uphills that is a BIG increase. Maybe not worth 5-600€ or more, but definitely worth 200! If I hadn't found this deal though I probably wouldn't switch. Or at least not yet, but might have waited for my current tires to wear out completely and then buy new wheels + tires.

    Thanks for the help, maybe this will help other people looking to make the switch.
  • email10wq
    email10wq Posts: 1
    edited September 2020
    Actually, there are plenty of resources online, which can help with that. I usually visit BikingBro.com blog and community, where experts have written tons of articles with needed recommendations and give practical advises how to fix anything related to bikes. And of course there plenty of articles, which can help in process of choosing a new bike.