Now that the UCI has allowed disc brakes in cross races, what do you cross experts think about it? Is that the way to go now? I’m looking into getting a CX rig, but I’m hesitant to buy a new one without disc tabs if discs truly are the future. I’m drooling over this new offering from Specialized (probably will never happen, though). Any thoughts? I’ll probably just end up getting a cheap used bike and then upgrading to discs in the future if need be.
On the sizing front, I had assumed that a CX bike should be bought small, so it would be easier to toss around the course. My 56cm road bike is just a tad too big, and my 54cm tri bike fits like a glove. So I was thinking 51 or 52cm for cross, but the shop said it should be the same as road sizing, 56 or 54 at the smallest. Does that sound right?
Disc brakes: depends on what kind of courses you’ll be doing ----- how much mud. If a lot of mud, discs would be good. Alternatively, I have seen people put an aftermarket disc cyclocross fork on a bike and run disc front and cantilever or V rear. I have raced in sunny Sacramento CA and discs would have been pointless. Up in Portland Oregon my poorly dialed in cantilever brakes sucked and I wish I had them.
Sizing: I would get a bike about the same size as your road bike ----- bike companies know what they’re doing and make the bikes to fit the way they want them to.
I doubt current disc brakes are the future of cross racing, even though disc brakes are the future of cross racing. Have you seen the new Felt ccx bike with disc brakes?
Is that a really obscure way of saying you think hydraulic discs are the future, but the currently-available, mechanical discs are not?
To OP: if buying a bike, get a bike with disc tabs, that way you have the option and don’t take any unneccessary hits on resale value. Or, negotiate a good deal on a bike that doesn’t have them; just like you’d get a deal on a new 2010 vehicle if there was a new body style or major feature on the 2011s.
On sizing, a 54 sounds right from your description. You’re going to want a more upright position, and if you’re 56 has you stretched out or at the limit of your spacers a similarly-sized 'cross bike is not going to be your friend.
I doubt current disc brakes are the future of cross racing, even though disc brakes are the future of cross racing. Have you seen the new Felt ccx bike with disc brakes?
Spot on.
DOn’t worry about discs for the time being, unless you live in an exceptionally muddy area.
The watershed moment for CX discs will be when suppliers develop a hydraulic brifter and smaller rotors designed for corss / road use.
I doubt current disc brakes are the future of cross racing, even though disc brakes are the future of cross racing. Have you seen the new Felt ccx bike with disc brakes?
Spot on.
DOn’t worry about discs for the time being, unless you live in an exceptionally muddy area.
The watershed moment for CX discs will be when suppliers develop a hydraulic brifter and smaller rotors designed for corss / road use.
Well, good point, but I guess doing all my racing in the Seattle, WA to Vancouver, BC corridor would qualify me as living “in an exceptionally muddy area”.
I’ve seen the argument about mechanical vs. hydraulic brakes, and honestly I don’t get it. Yes the hydros modulate better and are a bit smoother, but is the difference really that much?
if you’re racing in that area get disk brakes. I spent about an hour a week setting up my brakes last season because I wore through pads so fast racing in Portland (and yes I’m bad with cantilever brakes, but still, who wants to tune their brakes every week??)
Sure, but i was more talking about the size of the rotors being optimized for ccx. This shift may or may not render the current tab config useless. Remember DA7900 and DA7800 and the resulting non-interchangeability?
Motobecane sells a disc ready titanium cross bike for a great price ($1700-Rival / $2000-Ultegra). You can ride it out of the box with the canti’s it comes with and switch over to disc when the manufacturers come up with a lower cost alternative to the current hydraulic disc options. Sizing is manufacturer specific, you need to look at geometry charts and ride a few. The Motobecance frames ride big. I ride a 52cm road bike and went with the 49cm motobecane.
Is that a really obscure way of saying you think hydraulic discs are the future, but the currently-available, mechanical discs are not?
To OP: if buying a bike, get a bike with disc tabs, that way you have the option and don’t take any unneccessary hits on resale value. Or, negotiate a good deal on a bike that doesn’t have them; just like you’d get a deal on a new 2010 vehicle if there was a new body style or major feature on the 2011s.
Yeah, that’s what I was thinking, but a surprisingly low number of bikes that aren’t already spec’ed to the roof come with tabs. I’m sure that’s a result of the manufacturers playing catch up after the UCI allowed the discs.
Sure, but i was more talking about the size of the rotors being optimized for ccx. This shift may or may not render the current tab config useless. Remember DA7900 and DA7800 and the resulting non-interchangeability?
Oh shit, I hadn’t even thought of that. That would suck.
I’m on my second bike with disc brakes. I use the Avid 7 mechanical and am really happy with the whole package.
One other thing to consider is the rear spacing. I went with 135 hubs and basically have built up and have 29er wheels! The rear triangle on my bike was built with enough clearance to support up to a 2.0 mtb bike tire. I swap out wheels and can ride single track on my CX bike without the worry of pinch flats. When I race CX I put on the 303s with Dugast Tubulars and can rock the CX course with the traction that tubbies give. During the summer I have a set of wheels that I have put on Vittoria Pave 28mm clinchers and can ride the road with comfort and jump on the dirt with no problem.
Setting up a CX with disc brakes and a few wheel sets is like having multiple bikes.
Oh that’s sick - building up carbon tubulars with disc hubs. I would guess the rims would last way longer? You could ride them all year long - they would last forever!
On the sizing front, I had assumed that a CX bike should be bought small, so it would be easier to toss around the course. My 56cm road bike is just a tad too big, and my 54cm tri bike fits like a glove. So I was thinking 51 or 52cm for cross, but the shop said it should be the same as road sizing, 56 or 54 at the smallest. Does that sound right?
It depends on the specific bike geometry.
The reason I have heard/read 'cross bikes started with high BB (better to say low BB drop) is because with toe clips (old school) you needed to be able to pedal with you feet out of the clips briefly before and after obstacles. By raising the BB, the seat tube needed to shrink to get a reasonable standover height. Old school frame sizes used to actually measure (crazy, huh?) the seat tube either Center to Center or Center to Top. This was the frame size. In that case you would need to go down a size. (ex a 54 seat tube 'cross bike would have a similar stand over height as a 55 or 56 road bike.) Perhaps you get some better ground clearance, but this seems to be less important on a 'cross bike than on a MTB. With clipless mtn pedals, this higher BB could be reduced or eliminated.
The Specialized Crux has the same BB drop as the road bikes (it- the whole bike actually-is a little higher due to the greater width tires and therefore diameter) at 69mm. So if I road a 56cm Tarmac, I would by a 56cm Crux. Several of the current crop of 'cross bikes have more road bike like BB drop. Many of the Euro brands have a higher BB with less BB drop. If you buy a Ridley it has a BB drop of 59mm to 61mm depending on size. I would size down a bit on this bike.
The other factor if you choose to size down is that the top tube get shorter. I’m not sure this is a good trade off. If you get a longer stem to get close to your road bike position, it puts more weight on the front wheel than the next size up 'cross bike.
So the idea to size down on a 'cross bike comes from wider tires (effectively raising the bike up a bit) and less BB drop- both which reduce stand over height, but doing so may cause some other issues. The details of the bike geometry should point you in the right direction, there is not necessarily a universal rule.
Redline conquest dics frames have had tabs for about 8 years now. I think they were the first, but Lemond could have beat them to the punch with the poprad.