Colnago C60 rear tyre clearance

[Calnago]

Another data point:
Frame: C60 59Traditional
Wheelset: Vision Team 30 (19mm internal width)
Tires: Continental 4000Sii 25mm Clinchers

Ok, tallest 25mm tire I can find on a wide (19mm internal width) rim... While there is no rubbing the top of the fork crown or the rear brake bridge, the clearance is very very tight... too tight in my opinion. It would definitely drive me crazy with chatter from road debris getting thrown through there and while I don't mind if some paint rubs off the underside of forks or brake bridges from the occasional scuff... I don't like clearances so tight that when a small sharp piece of rock or debris sticks to the tire long enough to get jammed and pushed through between the tire and frame or fork that it actually "gouges" and scores the carbon. I think the potential for that happening is real with this combo. So, if you're running clincher rims with a 19mm internal width, then I'd stick with tires that are 24mm or less. But there aren't any clinchers I can think of that sit higher than the Contis so a different brand of 25mm tire might be ok as well. Still, I think a 17mm internal width clincher rim is really about ideal for road riding and using a 25mm tire. A 25mm tire on a 17mm internal width tire is plenty big. Can't really see wanting to go bigger till you get off road, but who knows where the madness will stop.

[fa63]

Thanks. I asked because I was wondering if larger size frames with longer chainstays have more clearance for larger tires.

[Bridgeman]

I had a high speed flat with a 25mm tire that resulted in finish damage. When full of air, I initially thought there was adequate clearance, but when deflated the tire expanded widthwise and rubbed the hell out of the frame as I was slowing on a slight downhill. Since I was front-mid pack I couldn't slow rapidly for fear of being rear-ended. This contributed to the extra abrasion.

One should keep this in mind when rolling with close clearance tires.

[Calnago]

Longer chainstays can certainly help with clearance in getting a bigger tire in and out of the frame for sure. But I think the brake bridge placement relative to the rim track is pretty constant across sizes. Also, I don't think I mentioned it in my last post, but those 25mm Contis on the 19mm internal width rims measured over 28mm wide, so pretty big.
Colnagos are really good with the chainstay and backside of the bottom bracket clearances both width wise and being able to push the wheel well forward to easily get it out of the frame. In fact, I just put that very same wheel into a different frame and because of the way the bottom bracket was molded it was definitely more challenging getting that wheel in and out. As long as you don't have to deflate your tire to get it in and out of the frame it's good. That can be a challenge on some road bikes with short chainstays and fat tires, or even not so short chainstays but a very "thick" molded bottom bracket area. So now, they're giving us fat tires, longer chainstays, and discs... at the expense of the tight handling we enjoy now, but shhhhh... we must not talk of things they take away, only of what they give. Ha.

[wedgie]

Thanks for all the opinions and advice. It would seem that the handmade manufacturing process of the C60 might result in very slight variations in tyre clearance from one frame to the next. Or maybe our opinions on what is acceptable clearance differs!

Has anyone experimented with a dropout shim or spacer similar to that used on a C59 fork that was discussed on a forum here - can't remember when. A 2mm spacer at the top of the dropout gives about 1.5mm extra clearance at the brake bridge, and still allows full clamping area at the quick release skewer. Clearance could be improved from around 2mm to about 3.5mm. Any thoughts?

[Bigger Gear]

I think there is just some general manufacturing variability with Colnago. I have a C60 size 54S, frame arrived in N America in Sept 2014. I have generally used Conti GP4000 II 700x23 on Enve 3.4 wheels with no clearance issues, but after reading this thread I thought I would play around a bit. For my bike the clearance is actually worse at the fork than the rear brake bridge. I had some Michelin Pro 4 700x25, which are known "oversized" 25s, mounted on DA 9000 C35 wheels. I could run the rear no problem with at least 2mm clearance, but the front is almost scraping the bottom of the fork crown. The wheel spins freely but there is no way I would try to ride it. I also tested Vittoria Open Pave 700x25, which is maybe a bit undersized but they are on HED C2 Belgium rims (17mm internal width) which plumps them up to around 26mm. I could run them easily front/rear, front clearance was around 1.5mm.

[Zakalwe]

Just man up and ride 19mm

[AJS914]

Tire size seems to be getting out of hand. Everybody wants to ride a full on racing bike yet run 28mm tires. Next year, people are going to be wanting to run 30s.

[Mockenrue]

Direct mounts and extra clearance on the UAE team's C60s at the E3. I wonder if this is now the norm on consumer frames.

[Calnago]

Wow, it that's a 27mm or larger tubular on there, then that's a completely new fork crown as well. Obviously it's a new fork, and rear seat stays, with the direct mount adaptation but from what I can see in the pic it looks like it could be much more clearance on both ends. Wish there was a better shot of the rear clearance. I'm finding a lot of bikes have enough clearance at either the front or the rear, but not the same at both. I've not seen any of the direct mount forks on new C60's yet.

Anyone know how much more clearance you get, if any, through the use of direct mount brake calipers? Say, compared to the new Dura Ace 9100 standard mount calipers which have really great clearance, at least up to 27-28mm tires. For example, could you fit a wide rim with a 30mm tire in them... I kind of doubt it, but don't know. Still would have to go to disc brakes for that I suppose, but at that size you should be off pavement anyway.

[corky]

Direct mount c60...... that has to come to production surely?

[Delorre]

Cal, check out the pics of the 60th anniversary c60. That frame already had direct mount brakes front and rear. Not on all pics though

F.ex : http://www.roadbikereview.com/reviews/sea-otter-colnago-c60-anniversary-edition

[beeatnik]

Goofy big haha.

28's ride like 25's. S'ok

[Zakalwe]

Direct mounts and extra clearance on the UAE team's C60s at the E3. I wonder if this is now the norm on consumer frames.

Picked up my frame last week, ordered in January - this wasn't offered as an option. Tall headtube was though, apparently they're the most popular geo at my dealers?

[Calnago]

@Beatnik: I'm with ya... Goofy Big! ha. I was just curious how big a tire one can fit under direct mount brakes versus standard mount, as in the new Dura Ace 9100. I stuffed a 27mm Veloflex Vlaanderen underneath a 9100 brakeset and there was tons of clearance. Plus, I still think the new Standard mount 9100 looks pretty sexy in comparison to all the direct mount "contraptions" out there. They're getting better, but still look a little prototypish/industrial to me at this point. Either way, I think 25mm tubulars are my road tire of choice these days. A 25mm clincher on a wider rim gets even bigger. It balloons out to like 28 or so on a slightly wider rim than normal, which is what I think you are showing in your pics above.

@Delorre: Thanks for that... I completely missed the 60th Anniversary party. That's a nice looking frame. Very clean.

And @Corky... yes, I can't see them not bringing that into production sooner than later.