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Cyclo-Cross on an MTB bike? Possible?(14 posts)

Cyclo-Cross on an MTB bike? Possible?Tahoe Gator
Apr 23, 2003 12:40 PM
Been thinking about how to avoid winter season fitness pitfall and cyclo-cross seems like a good way to get off the trainer. But, if i'm not serious about it (yet) and don't want to plop down for a new bike (yet), what about putting skinny knobs (as in 1.7 or something) on an XC mountain bike and racing that way? Sure, i won't win, but a) will they let me, or do I need drop down bars? and b) if i'm reasonably fit, could i expect to not come in dead last?
re: Cyclo-Cross on an MTB bike? Possible?weiwentg
Apr 23, 2003 8:18 PM
> but a) will they let me

yes, but no bar ends.

> or do I need drop down bars?


> and b) if i'm reasonably fit, could i expect to not come in dead last?

most likely you will not! CX races are mostly not technical enough that you'd be at an advantage on an MTB, but I've heard of some. on most courses you will be at a disadvantage, but it won't cripple you.
re: Cyclo-Cross on an MTB bike? Possible?atpjunkie
Apr 23, 2003 8:34 PM
and remove your bottle cages for portage. I'd have a rigid fork to swap out as well. race novice or beginner, you'll love it.
re: Cyclo-Cross on an MTB bike? Possible?Fixie-ated
Apr 24, 2003 4:24 AM
Better yet, do what I did and convert a mountain bike over to a full time cross machine.

If you have a retired mtn bike around, the remaining cost is reasonable.
re: Cyclo-Cross on an MTB bike? Possible?buffalosorrow
Apr 24, 2003 7:54 AM
ok fixie-ated's project, hands down is the best conversion I have seen. Adding drop bars typically elongates the reach too much, long mtb top tubes to blame. But if you can manage with a short stem and long extension, go for it. Although there is nothing wrong with flat bars (no bar-ends). The only thing I would recommend spending some money on would be a light rigid fork, shaves the weight for portage, and will keep you on track on the road sections.
Apr 24, 2003 11:05 AM
I had same questions several months ago. As others have said, take off bar ends and bottle cages and have at it. (One Caveat - if the race is a UCI race, you can't race with flat bars.)

I did two races at the end of last season on my hardtail. In both races I used standard 2.1 mountain tires. In the first race (Coyote Point - Northern CA) this worked fine. However, in a very muddy second race, this didn't work. The mud loaded up in chainstays and locked up the rear wheel. I had quite a long run to the pits to get enough clearance to get it rolling and finish but killed my chance of a decent placing. To solve the tire clearance issue, Continental makes a 26" in 1.5.

As for part b - sure why not? I managed a mid pack finish in my first race.

PS - after those two races, I sold my mtn bike and bought a 'cross bike. I'm really looking forward to this season.
UCI and flats...atpjunkie
Apr 24, 2003 11:17 AM
is this a new rule, as Frischi and the Swiss Team rode flats in the worlds just a few years back. Someone clarify. Personally I like the drops
UCI and deda synapsi carbon bar/stembuffalosorrow
Apr 24, 2003 1:07 PM
what about these bars and the UCI, they are legal for road races, but about cyclocross?
Tonight if I find $500 bucks under the pillow, Ill start going to chuch...
UCI and deda synapsi carbon bar/stematpjunkie
Apr 24, 2003 2:02 PM
I think forward triangle would be considered a bar extension and thus illegal in cx. You couldn't use top levers and tape on tops due to wing profile. Although legal I haven't seen these, or Cinelli Rams in the pro peloton yet. I don't think these would make good cx bars anyway. beyond design, there is too much quick vertical loading (bumps etc...) in cx for this material in this design. Carbon Fibre is stiff, it's material and make-up (weave) etc.. make for the vibration reducing factor but this is for hi frequency vibration (road chatter) and not for 'big hit' flex. severe flex or rapid flex to carbon breaks down or cracks the resin that binds the fibres together. This is the kind of force exhibited in cx. When overflexed, carbon fibre breaks. just watch Americas Cup sailing when (the absolutely best made) CF masts snap from flex. a mono stem and bar has too many points that would be exposed to these forces and therefore I wouldn't advise. CF or similar materials can be designed to flex (fishing rods for example) which are by taper (design) good for flex.
the butt of a rod (built to be stiff) is where failure takes place. no CF bike part to my knowledge (softride beam excluded) is designed to flex but to be stiff. this is going to start a flame I'm sure but I've worked with CF a bit and like fibreglass, it's the resin, it's not plastic and isn't good for flexing. If you watched Parix Roubaix or saw any of the info on the bikes they use, most teams switch from straighter carbon forks to ..........
dare I say it curved steel. I just went through this flame a month ago
so unless you are a Pro Mechanic, Bike Designer, Engineer or Physicist don't even freakin' start.
UCI and flats...outofthesaddle
Apr 24, 2003 1:13 PM
I was looking at Redline Cup here in Northern CA and saw this paraphrase of the UCI rules.

"Riders are responsible for knowing all UCI rules, including:
- CX bikes only (700c tires, 35c max width, drop bars)
- Lapped riders may be pulled. Riders lapped on the final lap may be assigned a finish ranking at referees' discretion.
- Bike and wheel exchanges in pit only
- International licenses required for Elite/U23 Men only (see notes below)"
UCI and flats...atpjunkie
Apr 24, 2003 2:44 PM
thanx, but I wonder when they were banned? and why?
UCI and flats...dlbcx
Apr 24, 2003 7:07 PM
Someone, like Clark Natwick, would probably have the answer to this question. Might be on the USA cycling website, too.
UCI does not prohibit flat bars only barendsjhr
Apr 25, 2003 5:15 AM
also no tire bigger than 34mm for uci races.

re: Cyclo-Cross on an MTB bike? Possible?GlowBoy
Apr 25, 2003 11:56 AM
Unless it's a UCI race (which most aren't) you can race on flat bars. Do take off the bar ends ... although at least in the beginner cat that I raced in last year, they didn't appear to be enforcing the rule: 2/3 of the field was mountain bikes and half of them still had their bar ends on. Go figure.

Anyway, get some good tires. Skinnier's better for mud clearance, though I'm not convinced width alone makes that much difference in rolling resistance, and remember there are wide variations in rolling resistance vs. grip even among tires within the same category. Also remember that the IRC, Schwalbe and Conti run notoriously skinnier than stated, so the tires from those companies that I list below aren't as wide as they sound. Some MTB tires known to be fast are:

Semislicks: Schwalbe Fast Fred Light 2.0 (the fastest mountain bike tire known to man), Conti Twister 1.9, Michelin Jet S 2.0, Ritchey SpeedMax 2.0. Probably none of these are great in mud, but would be nice and fast for racing on drier days.

Moderate knobbies: Michelin Comp S Light 1.9, IRC Serac 1.7; Ritchey ExcaVader 1.9, ZED Race 1.7 and (!) Z-Max 1.7. Some of these are probably better in mud than others - check the reviews at The Serac sounds very promising and I plan on picking up one soon myself.

And then for extreme mud there's the Conti Cross Country 1.5. With its extreme tread I bet it isn't the fastest roller, but a lot of people swear it is the best 26" tire ever for really sloppy 'cross courses.

- Dan