ttusomeone

I hesitated even posting this, but here it goes. Anyone tried using their CX bike as a spare crit bike? I rode my CX bike on the road a lot over the winter, and since it's due for an upgrade I'm planning to replace it with a new Crux. I've hear the geometry on the new Crux is closer to road geometry than previous editions. Ideally, I'd like to consider racing it in some during the local training crits (especially the sketchier ones).

Anyone tried this, and am I crazy for even thinking about it?

rubiksoval

You'll be that guy...hahaha. I'd have to think it's not optimized for going max-speed fast on the road, but I guess you could optimize it yourself. And if position is the same, probably wouldn't notice the difference. Is BB significantly higher?

What local sketchy crits?

ttusomeone

I'm guessing the BB is a little higher. I'm thinking of the MCC when it's the 180 or any time there's rain in the forecast out there...or simply to justify a reason to upgrade the CX bike.

furiousferret

Sure, you can do it, I've seen worse out there (Walmart bikes, downtube shifters) and if you're strong its not going to hold you back that much. Personally, if I had a road bike I'd use that regardless. Too many people get caught up on the concept of a crit bike.

spectastic

wheelbase might be a little wider than ideal. head tube might be longer prevent you from getting as low as your road bike. 160 mm rotors vs 140 mm rotors might expose you to more cross wind. 36/44 cross crankset should be replaced with a 52 or 53 big ring. handlebar might be a size wider. other than that, just put on road tires, and it should be just fine.

carpediemracing 

Other than gearing you should be fine on everything except the most technical course. I find that bigger gears really let me offload the aerobic system. Spinning like mad may be good for training but if you're trying to optimize performance you're putting yourself at a disadvantage if you give up the top 4 or 5 gears in a crit.

On the other hand I did do a race where I inadvertently ended up with a 39x11 top gear. Although I couldn't follow the winning moves, I normally wouldn't have been able to anyway, and I ended up winning the sprint from my group. That may not be significant but two guys that I have problems beating normally finished behind me, both known for their enormous big gears (both have a 54x11 at least, I think one runs a 55x11). I wouldn't start a race with the equivalent of a 39x11 or 42x12 or 53x15 on purpose. A 44x11 is the same as a 53x13 so on the cusp if you're not sprinting, there's no descent, or the wind isn't too strong (tailwind sections will hurt). Much better to have at least a 52 on there.

In this a guy on a cross bike (pro mtb to be fair) blasts his way through the field and I follow him:

There's another one where the guy on the cross bike is literally the best pedaler of the entire field, but I can't find the clip.

In terms of handling no biggie. My bike (a 40 cm c-c seat tube compact frame) has a 102 cm wheel base so that's not a concern. I'd be conscious of your longer chainstay for very technical courses where you're constantly switching directions, but in most crits that's not the case.

As far as BB height, shouldn't be an issue. I'm contemplating a cross bike like BB height, maybe 1.5 cm higher than normal, to try and get my bar height to a normal level, aka above the front tire. Right now it's about 1 cm below the tire. Some one off opinions, albeit from former world champions etc, seem to suggest that it shouldn't be a problem in crits.

rubiksoval

Do you notice a difference in BB height with cornering? It's one of those things where, in my head, I'd think it wouldn't make a significant difference, but at the same time, I'm thinking the higher center of gravity may be enough to notice, even thought it's relatively small. Especially on a course with a hard chicane where you're flipping your weight in a matter of seconds followed by two hard 180s.

On the flipside, the ability to pedal though a turn longer could be useful at times...

tommyrod74

Speaking from MTB (XC and DH) experience, as well as BMX, but it generalizes to road as well...

Higher BB actually helps with successive rapid turns - the bike is easier to swap from side to side. I've seen a physics discussion on it but forget the details - something about the higher COG and pendulum effect. I'm certain I'm butchering it, but that's what I recall. I've felt it on the trail with bikes that had adjustable BB height.

The lower BB helps with railing sweeping turns with the bike laid over, especially at high speeds. Just a very stable. planted, secure feeling when cornering. More difficult to rapidly swap the bike from a left lean to a right, though.

Someone will likely have a more technical explanation as to why this is so.

caloso

I have teammate who uses his Trek Boone as his only bike. Cross, road races, crits, whatever. He just switches wheelsets. It's not holding him back.

ttusomeone

I think I'm going to try it at some point this year. I just got a new road bike so have to sell my "old" one first, and then talk my wife into letting me upgrade my CX bike. Thanks for all the replies!

Psimet2001 

A ton of people around here do it. We are in the middle of Crit-landia and Cross-ville as well. Most well made cross bikes have geo that is between a road and track bike even. The longer wheelbases have gotten shorter and the BB height doesn't really make a huge difference. most people are more comfortable on their cross bikes anyway and exhibit better handling on them.

Tire swap and gearing of course. Swap the 1X in the front and have a real chainring or say goodbye to the field on the first lap.

macca33

tobukog

I wouldn't recommend it in crits with hard fast corners.

tommyrod74

Why not? Once acclimated to the handling it should be perfectly capable. The high BB might actually be nice on certain courses.

tobukog

If it's a slow course, it probably wouldn't matter. On a fast course with hard cornering, especially if the finish is right after the last corner, a cross bike requires too many inputs to really be effective -- the longer chain stays usually make it nose heavy and requires you to shift your weight back every time you get to mid corner. It just makes for a really busy ride and keeps you from concentrating on winning the race. I used to ride a look with the opposite problem, the top tube was way too long and I constantly had to pull forward in a hard corner.

rubiksoval

I only ride road bikes, but on a last corner before the finish (or any corner I'm taking at my limit) I'm hanging off the back outside edge of my seat as far as I can.

And what does "concentrating on winning a race" mean when you're in the middle of a final corner? I don't ever remember actively "thinking or concentrating" in the last few hundred meters of a race. It's just react and go.

tobukog

My sentiments exactly. The less you have to think about actively piloting the bike, the better you're going to be in a crit. Of course you shouldn't be concentrating on winning a race in the last corner, you should be reacting. But if you have your hands full steering the bike in a crit, that's where your mental energy will be and will make it challenging to be in a winning position. It's best to pick the right tool for the job -- a cx bike is not a road bike with more clearance -- and you won't find very many of them being used in a higher level criterium.