New bike and tyres 23mm v's 25mm ?

andy335touring

Hi, I've not long started cycling to work(3 months) 2/3 times a week on a cheap second hand hybrid, it's 8-9 miles each way depending which route I take.

I'm looking into changing to a half decent starter road bike to carry on going to work but also do some longer rides. Being 16 1/2 stone(coming down steadily) and the state of the roads, is there much difference in terms of comfort/less chance of damaging the rims going from 23 to 25mm tyres ?

My limited understanding is that most racers that come with 23 tyres only have the scope to fit 25 if you want to fit bigger tyres ? I might take a drive up to planet x this afternoon to see how big a tyre you can fit on the bike I'm interested in.

I did think about a CX but they seem I little expensive compared to the spec/weight of a racer ?

A little more about me and the bike I'm looking at.

6ft
40 yo
16 1/2 stone

Planet X RT-58 Alloy Shimano Tiagra Road Bike

http://www.planetx.co.uk/i/q/CBPXRT58ALUTIA/planet-x-rt-58-alloy-shimano-tiagra-road-bike#customise

Frame: Planet X RT-58 Alloy Road Frame
Fork: Planet X RT-58 Carbon Road Fork
Front Derailleur: Shimano Tiagra FD-4600 Double 10 Speed Front Mech / Braze On / Conventional Swing / Silver
Rear Derailleur: Shimano Tiagra RD-4601 Rear Mech / Road / Short Cage / 10 Speed
Shifters: Shimano Tiagra ST-4600 STI Levers
Chainset: FSA Gossamer Compact BB386 EVO Chainset
Crank length: 172.5 mm
Chainrings: 50-34T
Bottom Bracket: BSA
Cassette: Shimano Tiagra CS-4600 Cassette / 10 Speed / 12-25
Chain: Shimano Tiagra CN-4601 10 Speed 114 Links
Front Brake: Shimano Tiagra BR-4600 Road Brake Caliper / Front / Front
Rear Brake: Shimano Tiagra BR-4600 Road Brake Caliper / Rear
Handlebars: Planet X Road Bar Strada Shallow Drop / Polished Black
Bar tape: Planet XCork Handlebar Tape
Grips: N/A
Stem: Planet X Superlight Team 3D Forged Stem 100 mm / Polished Black
Headset: FSA Orbit C-40 No.42 ACB-1
Wheels: Shimano R501 C24 Clincher Wheelset
Front Tyre: Continental Ultrasport Wire Bead Tyre / 700c / Black / 23 mm
Rear Tyre: Continental Ultrasport Wire Bead Tyre / 700c / Black / 23 mm
Inner Tube: Planet X 700c Road Inner Tube
Saddle: San Marco Ponza Saddle / Carbon Steel / White
Seatpost: Planet X Light Alloy Seatpost / 31.6mm / Polished Black
Seat Clamp: Kalloy Pro Alloy Seatclamp / 35.0mm
Mudflap compatible: No
Pannier rack compatible: No
Pedals: Available Separately
Bottle cage bosses: 2 sets
Number of Gears: 20
Weight: 8.84kg (19lb09oz)

terryhughes

I've put 28mm Schwalbe marathons on my Boardman Comp and it fits fine. More comfort and around 90-100 psi. Makes a huge difference along with carbon forks.

andy335touring

Thanks for the info, touch wood the RT-58 can fit 28mm

ManOfKent

Current thinking is that up to a point, wider is better for both comfort and speed. That said, tyres are not always the width they're advertised as, so you might find one manufacturer's 25mm is the same as another's 23mm.

Even at your weight tyre width shouldn't affect the risk of damaging the rims.

andy335touring

Nice info, thanks

I thought my weight might have been a problem, I guess so long as I'm careful I should be ok ?

Miles253

Ive found since ive moved to 25mm tyres, that along with lower pressures i feel less road buzz, and big hits are reduced. I think it wasn't as noticeable as i was expecting however.

That bike youre looking it, i feel is unlikely to be able to fit 28mm tyres, not for sure, but lack of mudguards eyelets can be a giveaway.

IShaggy

Unfortunately not all frames have clearance for 25mm tyres.

I run 28mm tyres on my commuter, a 25mm rear on my winter wheels, and 23mm elsewhere. I run 85-90psi, 90psi, and 100psi respectively. I really don't notice much difference between the sizes. But then as others have commented already, different tyres come up at different widths, and also the tyres sit differently depending on rim depth and width.

But I am only 73kg. Maybe if I was heavier, and hence had to run higher pressures in the 23s then I'd notice a diffrence.

smoggysteve

I started using 25mm Schwalbe 1's on my Bianchi. They have just enough clearance but I cannot get the rear on or off if inflated.

andy335touring

Thanks for the feed back, i'll have to ask them tomorrow about bigger tyres.

Looks like they do a half price retul bike fit if you buy a bike from them, as I don't know or have the experience to set a bike up properly I think it would be a good idea to have a fit ? Has any one had a bike fit from the Sheffield branch of plantet X ?

I'm thinking of getting some Look Keo Easy Pedals from them but going else where for my shoes. I'm looking at Shimano R088 Road SPD Shoes 2014 as they're listed to be compatible Look pedals ? Dose this seem a decent choice ?

So I guess I just need some lycra shorts/top for the bike fit/longer rides ?

pre0ats

andy335touring wrote:

Looks like they do a half price retul bike fit if you buy a bike from them, as I don't know or have the experience to set a bike up properly I think it would be a good idea to have a fit ? Has any one had a bike fit from the Sheffield branch of plantet X ?

I had a half price fit when I bought my bike from Plant X last year - in fact I booked a half price 'double fit' (usually £250.00) for a mate and I and split the cost, so it was only approx. £60 each.

I am sure it's not the full experience you get if paying full price, but as a novice (my first road bike) I found it helpful and now have a set-up that really suits me (e.g. he changed the stem length, as well as the seat height and set-back).

I thought if I'm spending all that money on a bike, why not spend a little more to get it set up right rather than guessing.

ai_1

If your're fairly heavy then it makes more sense to use a bigger diameter tyre. The bigger the tyre the lower the pressure you can run which provides better grip and better comfort without any significant positive or negative impact on speed. As others have said the nominal dimensions of 23mm or 25mm that tyres are sold as may not correspond exactly to the actual tyre dimensions. For example Michelin Pro 4 SC tyres are reported to come up around 22mm for "23mm tyres" and around 27-28mm for "25mm tyres". this will vary a little depending on the rim too. I wouldn't buy a bike that wouldn't take a real world 25mm tyre. Most will.

terryhughes wrote:

I've put 28mm Schwalbe marathons on my Boardman Comp and it fits fine. More comfort and around 90-100 psi. Makes a huge difference along with carbon forks.

That's a very high pressure to run on 28mm tyres. There's not a huge advanatge in using bigger tyres unless you drop the pressure. I'm not light, I weigh about 86kg (13st 8lbs approx) and I run my 25mm Yksion Pro tyres at around 85-95psi at the back and 70-85psi at the front. The lower end of those ranges is best for long rides on bad roads, the upper end is good on smooth roads and if I might do some out of the saddle sprints as I like tyres a little firmer in those situations. If I was a similar weight to the OP I might add a few psi but I doubt I'd exceed 100psi on 25mm tyres. With 28mm tyres you can go significantly lower than this. I'd probably drop another 10psi at the back and maybe a little less than that at the front. You can experiment with it but so long as you're not getting pinch punctures you've got enough pressure. Lower pressure provides better grip and comfort but you may find that going very low makes it feel a little mushy when you get out of the saddle to climb or sprint.

spm0912

I've a planet x RT 58 that came with 23mm Conti gatorskins. After a couple of weeks I thought I'd made a big mistake buying a road race bike. I felt every bump on the road and ended rides with numb hands.
LBS recommended changing to 25mm Conti GP4000. Wow, night and day difference, I doubt there's the clearance for 28mm tyres on the RT 58, it'll certainly be tight

andy335touring

pre0ats wrote:

I thought if I'm spending all that money on a bike, why not spend a little more to get it set up right rather than guessing.

Exactly what I thought. Plus like you say, if some thing does need swapping out it doesn't cost any thing. I've got fairly dumpy legs for my height so I might need a shorter crank ?

You have a look around on the internet for post fit feed back and there's a few people say they gained an average 1-2mph, now you could take that with a pinch of salt, but if true it's good value for money v's spending hundreds of £££ on lightening mods.

Ai_1, nice info, thanks. It give's me a starting point on what sort of PSI I should use.

Yesterday I took a drive up and ordered the bike, sods law there's one part out of stock but it's due in this week touch wood.

I've ordered it in black/white and a med/54cm frame, I'm just under 6ft. Changed the stock cassette from 11-25 to 12-28 as I'm not the best when it come to hills.

I was going to order it with Michelin Pro 4 SC in 25cc but they were out of stock which is a shame because they where a lot cheaper than the Continental Grand Prix 4000s Folding Tyre that I ended up getting. Both tyres are highly rated on here from what I've read but the 4000s aren't cheap !

spm0912, nice to know the 25mm 4000s made such a nice improvement and if you use them on yours I know they'll fit.

drummer_boy

I'm 17st and usually ride 28mm road tyres on my PX XLS. I borrowed a mates alloy road bike to do a sportive last weekend, after I broke my mech hanger, and it came with 23mm tyres.

Biggest difference was comfort. My speed was about where it normally it, but it seemed like i could feel every little lump and bump in the road.

On there wheels, PX themselves say they'll take a 28mm: http://www.planetx.co.uk/i/q/WPSH501/sh ... r-wheelset

ianbar

i have 25mm but on slightly wider rims, the difference is massive! soooo much more comfort and the grip is fantastic, defending way faster too.

kajjal

I was over 16 stone and found 23mm tyres fine at 105psi but the roads are quite smooth round our way. If they were a bit rougher I would go for slightly wider tyres. I have had no problems with punctures.

The trick with tyres is to find the right balance for you between too low pressure alot of punctures and too high a pressure and getting loads of vibration.

andy335touring

Thanks for all the info, I might have looked into 28mm tyres but I don't want to jinx the imminent build.

Things have gone a hell of a lot quicker than I thought they would as I've got a build date through and it's for this Monday !

I thought they were normally 21 days ?

I've not got around to ordering my shoes yet as I was expecting a longer wait and i'll need them for the fit :oops:

I think I'm going to buy the shoes locally rather than ordering online only to have them turn up and not fit properly.