Every once in a while, I do something here that isn't a race report. I've been meaning to get this one out for a while, now, because it's EARLY CROSS SEASON which means that all anyone ever talks about is how other people need to upgrade.
Personally, I don't spend as much time worrying about sandbaggers as my twitter account might suggest. Such is the advantage of racing in the only category you can't sandbag.
I've been racing cross for six years now and one thing has never changed: people act like the jump between categories is much larger than it is. The standard refrain when someone upgrades to Cat 3 is "well, now it's time to get lapped!" and that is... um... not even remotely true. If you're fast enough to get any kind of merit-based promotion out of Cat 4, then you're already riding at midpack Cat 3 speed.
In fact, this is true for Cat 3->Cat 2 as well. The only catch is that with Elite Men riding up to 10 laps, you can be a mere 10% slower than Jeremy Powers and still get lapped on a short course. So fast Cat 3's are both midpack Cat 2's and in danger of getting lapped. Tricksy!
Quick aside: this is why "getting lapped" isn't an indicator that you don't belong in the elite men's race. 10% back in ANY other field and you're comfortably on the lead lap.
Anyway, to really see the way the fields compare, we can look at lap times on a day when the conditions don't change much. Providence Day 1 is a good example from the recent season.
Obviously, riding more laps will slow down your average lap time, but not as much as you might think. One underrated factor when you move up is that you start racing with faster racers; so you're riding longer, but you're getting more drafting opportunities than you used to. For example, Curtis White won Cat 3 solo by a large margin -- if he'd been in the Elite race he'd have been riding in groups all day instead of eating a steady diet of wind. The chase group behind him (Delinks, Dobie, Herrick) would have been in groups in the elite race as well, but instead of racing for 2nd (and playing cat-n-mouse) they'd have been in the 30s, where guys tend to work together to survive instead of fighting each other for the podium.
So, yes, riding longer is hard. You will go a little slower. Not as much as you think.
Graph time! Here's a bar graph showing the lap times spanned by each field. Note that if you get lapped, I can't tell what kind of lap times you were turning, so this is showing the range of times ON THE LEAD LAP.
Time for some fun facts!
The 35+ Men's race and Cat 3 race have almost exactly the same range of times, but the Cat 3 field has almost twice as many guys in it. This is probably why people talk about how civilized the 35+ race is compared to Cat 3... there's just way fewer bodies out there.
The Cat 3 winner, Curtis White*, would have been 28th/57 in elite men if he could've held his pace for 2 more laps. But he wasn't alone. The top 25 guys in Cat 3 were all turning fast enough laps to make lead lap in the men's race. If they could've held their pace for just one more lap, they'd have made it onto the final lap before Justin Lindine finished.
Conversely, if you didn't make the lead lap of the Elite Men's race, this should tell you how you'd fare in the current Cat 3 race.
The Cat 4 winner, Maksym Shepitko, was on pace for 27th/127 in Cat 3 if he could've held his pace for 2 more laps. Seriously. If you're winning Cat 4, you're good enough to beat 100 CAT 3's.
The 35+ winner, Bill Elliston was doing lap times good enough for 25th/57 in Elite Men, and would have won the Cat 3 race by 40 seconds.
Onto the women!
The Cat 3/4 women's winner, Ellen Noble**, was doing lap times good enough for 21st/37 in Elite Women.
The top 22 women in 3/4 were turning lap times good enough to be "not-last" in Elite Women (everyone made the lead lap).
The HARDEST upgrade in CX is going from Cat 4 35+ to 35+ -- the winner of Cat 4 35+ would have to ride 2 extra laps at his winning pace just to get 54th/61 in 35+!
So, what does it all mean?
It means that if you're fast enough to get anywhere NEAR the sandbagger discussion, you're fast enough to move up a category and not be last. This is true for Cat 4, Cat 3, and Cat 3/4 women -- if you made top 20 in those races, you'd be fine moving up, assuming your definition of "fine" is "not embarrassingly overmatched."
Note that this is NOT the same as "you should move up." You should move up when you want to, or when the heckling from your peers becomes unbearable. My only point here is that you would almost certainly survive upgrading, despite what you may believe.
Update! Bonus Cross-Gender Fun Facts!
Ellen Noble would have been 8th in Cat 4 men and 2nd in Cat 4 35+.
Laura Van Gilder would have been 7th in Cat 3 men, 6th in 45+ and 18th in 35+. She would have just barely made the lead lap in the men's elite race.
The Elite women's race is the exact same distance as 45+ and has virtually the same lap times from top to bottom, but only half as many riders.
Super-double-bonus LVG update!
Laura Van Gilder is 46, so if she raced 45+ no one could complain about her age***
Triple-bonus LVG update!
Laura Van Gilder is really good at racing bikes.
*Unfortunately, Curtis is a Junior and can't upgrade because the UCI sucks.
**Unfortunately, Ellen is a Junior and can't upgrade because the UCI sucks.
***Some of the fastest 45+ guys race 35+, so she's not even close to being the fastest 45+ rider out there. Sadly.