Cyclocross - Race strategy and technique questions

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daroemer
11-14-07, 07:54 PM
I am ready to run my 2nd race. The first race was more about getting familiar with how things will go, gauge the level of competition in the local series, make sure I don't kill myself or anyone else...you know, the basics. I did that race on a borrowed MTB, but now have my own "cross" bike, and it's time to start taking this career seriously :)

So I'm hoping to improve on my performance, and actually think about what I'm doing versus just trying to stay out of everyones' way, and have a couple of questions that I'd like opinions on:

1. What kind of tire pressure is typical for you experienced racers. I realize it can vary from course to course, and condition to condition, but how about a range, or some examples? i.e.:

Mostly hardpan/pavement, dry conditions: Would I run all the way close to max pressure for this, or still back it down some due to the fact that there will be some turns in the junk (if so, how much)?

Woodsy, hilly, grassy, dry conditions: Any more or less pressure if there is more "off road" type condition than pavement/hardpan?

What about either of these when the weather gets poorer? Colder? Muddier? Snowier?

I ask because I was at the USGP here in L'Ville, and the Pros that we pit crewed for (Chris Jones and Adam Myerson) were running 28 psi in the front and 30 in the rear (or vice versa, I can't remember). Pretty low pressure, I thought. It was a dingy, damp, cold day. I forgot to ask what they ran on Sunday, which was sunnier, warmer, and much drier. I just ran into a local guy practicing out at the same course the other day with 80 psi or something crazy, although it was his first time out, so that wasn't thought out, I know? I've been riding around at about 30 psi (you know, what's good for the pros...), but it sure seems like a lot of work on the flat, "fast" sections. It clearly helps on the technical sections, but maybe I've gone too far (?).

2) How much ettiquite is involved in these races? I mean, I think I'm in pretty good shape, and can hang pretty good for the 30+ minutes -- I am not a road cyclist, or any kind of cyclist at that, but at the end of my first race, I was running by folks up the hills, carrying this heavy mtb, and making up good ground -- but DO NOT want to be in the way while I'm learning the ropes. I do, however, want to finish well, and don't want to just move over every time another rider comes up on me. There were numerous occasions in the first race, where I just moved over when any racers approached from behind on flatter or "easier" sections of the course (EVERYONE was a better cyclist than me), only to be held up by the same person on more narrow, technical sections or run-ups. Had I been more of a jerk and made an effort to keep them behind me, I could have stayed ahead of them, possibly, and made up ground on those run-ups. What's the expectation? I definitely realize that if I'm being lapped by leaders I need to get out of the way so as not to influence the actual finish, but what about other racers in general?

3) This sort of goes with #2, but I am interested in how to handle the start (twofold, really).
a) Being so new, what is expected at the start from me? Should I just let the field go and then pass the people I can pass, or can I try my hardest at the start, knowing I might end up in front of riders who are much better, at the risk of holding them up and effecting the finish?
b) This is technique, not ettiquite -- How do you start a sprint from a dead stop? Do you start in a middle gear and just work from there, or do you start lower, and keep shifting as you gain speed? Is it good to shift a lot during a sprint like that (it seems like that might put unwanted pressure on the chain)?

4) lastly, what is this talk of "glueing" tires? Maybe this is super basic stuff, but I don't think my tires are glued on. Is this something special for Pro racers? I've heard of tubeless tires, so maybe it has something to do with that? Do I need to know anything about this glueing?

Any other advice or tips you can think of from when you were at your 2nd or 3rd race would be great. Past the "I wonder what is going to happen?" 1st race feeling, and on to the "what should I be doing to be a 'real' participant?" stage...

Thanks,

DR


ZeCanon
11-14-07, 10:34 PM
1. What kind of tire pressure is typical for you experienced racers. I realize it can vary from course to course, and condition to condition, but how about a range, or some examples?

The pros are running low tire pressures because it is actually much faster. While you may feel like you're going faster with higher tire pressure, unless the course is exceptionally smooth you are just getting what I call the "jeep effect": driving 50mph on a jeep road feels a lot faster than 50mph on a highway because it is so much rougher. Same thing with high tire pressure - it just feels faster because you are getting bounced around more.
With low tire pressure, your tire conforms to the bumps, wasting much less energy than if your whole body/bike has to be lifted in the air by a bump. Rolling resistance goes down dramatically.



3) This sort of goes with #2, but I am interested in how to handle the start (twofold, really).
a) Being so new, what is expected at the start from me? Should I just let the field go and then pass the people I can pass, or can I try my hardest at the start, knowing I might end up in front of riders who are much better, at the risk of holding them up and effecting the finish?
b) This is technique, not ettiquite -- How do you start a sprint from a dead stop? Do you start in a middle gear and just work from there, or do you start lower, and keep shifting as you gain speed? Is it good to shift a lot during a sprint like that (it seems like that might put unwanted pressure on the chain)?

3) Start as hard and fast as you can. Position in the beginning of the race is exceptionally important, especially in larger fields. If you beat people in the start and they have to pass you later, tough luck for them, they should have started faster.
a) see above
b) I run a single 44t ring up front, and start in a my 19t cog if the start is flat. I just shift from there. You want to be able to wind up your starting gear within the first 15 yards, then shift up. Find what works for you.
There is a certain technique for shifting under load that you have to learn on your own. Practice your starts, going from zero to 120% of race pace.
That said, unless you start on the front line of your races, you won't be all-out sprinting at the start of any race because you'll be stuck behind people.



4) lastly, what is this talk of "glueing" tires? Maybe this is super basic stuff, but I don't think my tires are glued on. Is this something special for Pro racers? I've heard of tubeless tires, so maybe it has something to do with that? Do I need to know anything about this glueing?

I mentioned tubulars earlier in my post. For cross, there are three common types of tires: clinchers, tubulars, and tubular/clinchers (i guess that's what they are called)
Clinchers: the standard rim/tire setup you are used to. Tire has a bead, rim has a bead hook, they fit together with a tube inside.
Tubulars: much older than clinchers, used a lot on road bikes. Basically, the tire is self-contained, with no tube necessary. You use different rims, without a bead hook, and glue the tires onto the rims. Tire pressure and the glue holds the tire on.
Tubular rim: http://www.parktool.com/images_inc/repair_help/glue50.jpg
Tubular Tire: http://www.velocity-cycle.com/images/acc-wheels/conti-Giro.jpg

Tubular clincher: a tubular tire that fits on a clincher rim with the use a rubber strip at the bottom of the tubular for holding onto the bead hooks of clincher rims.
Tubular Clincher tire: http://www.biketiresdirect.com/images/tufotubclinch.jpg

Tubulars provide excellent flat protection, as pinch flats are nearly impossible to get, and which is why you can run such low pressures with them. They are also said to be more "supple" and thus faster, but this is highly subjective. I run tubulars and find the ride to be much nicer than with clinchers. But for me the real advantage is flat protection.

daroemer
11-15-07, 12:58 PM
Very helpful! Thanks. Regarding the tire conversation then, it sounds like I may want to keep the pressure low(ish) for better speed/control, but should I err on the side of slightly too much pressure, since I have clinchers, and run a higher risk of pinch flat?


flargle
11-15-07, 01:38 PM
Cross-posting is bad etiquette.

As far as cyclocross, this maneuver is generally considered to be poor sportsmanship:
http://youtube.com/watch?v=wNjVcYbJ4x4

daroemer
11-15-07, 06:56 PM
Sorry about that. I posted here, then realized it was better suited for the "cyclocross racing" sub-category. This one could be moved or deleted.

field3
11-27-07, 10:09 AM
Hey ZeCanon...

The Tub/Cli look pretty appealing as they provide the best of both worlds... are there any more manufactures other than TUFO? They seem really price too!



Tubular clincher: a tubular tire that fits on a clincher rim with the use a rubber strip at the bottom of the tubular for holding onto the bead hooks of clincher rims.
Tubular Clincher tire: http://www.biketiresdirect.com/images/tufotubclinch.jpg