Question: tire size on Colnago C50

b33 · #1 02-28-2021, 11:31 AM

Aquired a mint Colnago c50 last year. My question is on tire size. Seems 23mm is the way to go - what I wanted to ask is what is the combo to get the largest 23mm with clearence in a C50.

I've been told that Vitorria 23mm comes out wider than veloflex 23mm? Is this true? Do I need to stick to a C15 rim or can I go C17?

Any input would be appreciated.

jpritchet74 · #2 02-28-2021, 11:48 AM

Veloflex usually measure 1mm narrower than the listed width. Vittoria is either at listed width or 1mm larger.

BUT, a 25mm Veloflex at 24mm actual width may be the same width as a Vittoria 23mm that measures 24mm.

I wish I would have seen this an hour ago and I could have measured my 23mm Vittoria tire.......

Adam · #3 02-28-2021, 11:51 AM

FWIW I have a 25 mm Vittoria Rubino on 17mm wide Mavic rims on my C40 HP and they clear fine.

MoparPorsche · #4 02-28-2021, 12:00 PM

I have heard of anyone having issues with putting 25s on a C50 as much as with C59. I have 27mm Challenge Paris Roubaix on one of my C40 and Vittoria Corsa 25s on another, and Vittoria Corsa Graphene 2.0 25s on an EPS.

C40_guy · #5 02-28-2021, 12:26 PM

Congrats on the purchase!

I run 25mm Conti 4000s on Campy Eurus wheels.

And I am not happy with the clearance. I've done it for 10 years, and haven't had an issue, but the clearance at the chainstay is minimal, and clearance to the front fork (crown) is not terrific.

That having been said, the Conti 25mm is a big tire.

C40_guy · #6 02-28-2021, 12:28 PM

Quote:

Originally Posted by Adam

FWIW I have a 25 mm Vittoria Rubino on 17mm wide Mavic rims on my C40 HP and they clear fine.

I *think* the C40 has slightly more clearance than the C50. I don't remember having clearance issues on my C40 with Conti 25mm tires...

I did have clearance issues with 23mm Contis on my Spiral Conic SLX. Had to deflate tires to mount/dismount or they wouldn't clear the seat tube! Hoping this isn't the case with my Master Olympic...

My C50 is a MKII, 50cm or thereabouts.

slambers3 · #7 02-28-2021, 01:17 PM

I can give some direct feedback on this- mine clears Vittoria corsa 25mm tires on Campagnolo C15s with zero issue...most of the miles I’ve done on my c50 have been on this setup. I got a little bit cocky and tried challenge paris-roubaix 27mm tires which measured more like 29mm, these rubbed a bit on fork crown so I swapped them back after one ride.
Depending on the rim, the Vittorias measure a little larger than labeled, veloflex masters tend to run smaller.
My C50 is a 61cm for reference.

jimoots · #8 02-28-2021, 04:19 PM

I run Conti GP5000s 25mm tyres (which are very tall for a 25) on my C50 era Extreme Power (with Star Fork) and EPS (with what I think is a C75 fork - it's got EPS graphics, not C75) without any issue.

Admittedly both are non-HP stay but I'd be surprised if you can't run a 25 on a C50. The C59 is where things got a little weird and it was a 23mm only affair.

MoparPorsche · #9 02-28-2021, 09:22 PM

Quote:

Originally Posted by slambers3

I can give some direct feedback on this- mine clears Vittoria corsa 25mm tires on Campagnolo C15s with zero issue...most of the miles I’ve done on my c50 have been on this setup. I got a little bit cocky and tried challenge paris-roubaix 27mm tires which measured more like 29mm, these rubbed a bit on fork crown so I swapped them back after one ride.
Depending on the rim, the Vittorias measure a little larger than labeled, veloflex masters tend to run smaller.
My C50 is a 61cm for reference.

What you do with the Challenge paris-roubaix tires, love them?

b33 · #10 03-01-2021, 08:07 AM

Thank you for the replies!!!!

I was able to fit some 25mm Vittoria roubino pro tires mounted to C17 fulcrum racing zero - using the old Allen key seems I have 2mm in the back and 2.5mm in front for clearance - this will be a road-only machine - do we think that is adequate?

C40_guy · #11 03-01-2021, 08:39 AM

Quote:

Originally Posted by b33

Thank you for the replies!!!!

I was able to fit some 25mm Vittoria roubino pro tires mounted to C17 fulcrum racing zero - using the old Allen key seems I have 2mm in the back and 2.5mm in front for clearance - this will be a road-only machine - do we think that is adequate?

It will be fine. Unless, of course, you pick up that one lone piece of 3mm gravel and try to squeeze it between tire and chainstay.

Hasn't happened to me yet in ten years of riding a similarly narrow gap...

b33 · #12 03-01-2021, 09:43 AM

Haha - makes sense to me. Thank you very much!

Quote:

Originally Posted by C40_guy

It will be fine. Unless, of course, you pick up that one lone piece of 3mm gravel and try to squeeze it between tire and chainstay.

Hasn't happened to me yet in ten years of riding a similarly narrow gap...

prototoast · #13 03-01-2021, 09:46 AM

Quote:

Originally Posted by b33

Thank you for the replies!!!!

I was able to fit some 25mm Vittoria roubino pro tires mounted to C17 fulcrum racing zero - using the old Allen key seems I have 2mm in the back and 2.5mm in front for clearance - this will be a road-only machine - do we think that is adequate?

It will mostly be adequate. Paint will get scratched up a bit. Every once in a while you might have to stop and pull a pebble out.

C40_guy · #14 03-01-2021, 10:04 AM

Quote:

Originally Posted by b33

Haha - makes sense to me. Thank you very much!

BTW, I should change my ID to C50_guy as I made that move ten years ago.

texbike · #15 03-01-2021, 11:58 AM

Quote:

Originally Posted by C40_guy

BTW, I should change my ID to C50_guy as I made that move ten years ago.

^Nah, it just means that you need another C40.

My C50 doesn't fit 25c Contis on either 15 or 17 inner-width wheels. The issue is primarily with the fork (the tires won't clear once you put some weight on the bike!), although the rear brake bridge clearance is almost as bad. So, for my particular bike, wider 25cs are a no-go. Regardless, it still rides great.

Texbike