Cyclocross - How do you fit a cyclocross bike?

[Ozz]

How does the fit of one's road bike translate over to a cyclo-x bike?

My CSI is a 60 ST x 58 TT w/ 11cm stem

What size cyclocross bike should I be looking at?

Thanks.

[coylifut]

Frame size should be about the same. No. You don't need more stand over. If you are stradling your top tube, something has gone horribly wrong. The general rule of thumb is that the saddle slides back 1 cm, seat height is adjusted down one cm, bars are up 1 cm and reach is 1 cm shorter. With that said, my cross and road positions are the same. Oh yes, cross is in the air. I can hear the cow bells ringing and taste the beer flowing.

[dbrk]

Actually I like exactly the same position points of contact---same saddle height, same bar height, same everything---but with a slightly smaller or even small slope in the frame. This leaping on and off stuff and then hauling up a hill has a way of inviting a bit more clearance but maintaining large enough triangle to shoulder the bike. But if you are not going to race, if you are just going to go bounding about (my current preference) then clearance is also moot as is portage inside the triangle. To wit, my custom Moots PsychloYBB is way better for bounding about than for racing because it's got about 5d of slope. I raced last on my IF (once Dr Cotcamp's bike which he too raced) but now that it's pink and I'm a sissy I may not race it again. I also have an Oswald cross bike, a beautifully built, excellent ride, where the points of contact are nearly identical but the frame is smaller than my usual ride 'cause it's for gettin' on and off (as one does in real 'cross).

My backyard provides the most challenging cross course I have ever attempted. Lots of trails, some long straight dirt driveway, and a descent that invites care because, well, if you miss it at the bottom you will go straight into the pond. 'Cross is waaaay more fun to me than mountain biking. I can stand the on and off stuff on 'cross but the falling over and fits and starts stuff of mtn biking has never appealed to me. To each his own!

get yourself the same size cross bike as yer road bike, and make sure it doesn't raise the bb to stupit [sic] heights,

dbrk

[Andreu]

I raced cyclocross a few years ago. The only thing I would add is that the races I did seemed to change over the space of 5 years because there were more mountain bikes at the event and the organisers (maybe more Mountain bike orientated) changed the courses so the downhills were more technical (generally steeper and with more technical bits e.g. rocks etc) this is difficult if you have the exact same set up as your road bike. For me, racing down really steep hills with your nose over the front wheel did not fill me with a great sense of security - You probably want a slightly more upright position with the ability to get weight back on the bike quickly. It is difiicult to describe without seeing you on a bike and the best thing to do is go and talk to a bike shop (builder? - IF?) who specialises in this sort of bike. And also this is my personal preference if I were racing cyclocross again. Actually, I am not a big fan of sloping top tubes but I can see the advantages of this set-up on a cyclocross frame!

Remember, this also gives you the ability to go out with the mountain bike boys and girls too....its a great feeling watching jaws drop when you appear on a cyclocross bike for a run out in the mountains!
A :beer:

[Andreu]

DBRK - any suggestions on a cyclocross frame builder - the only one I can find apart from Serotta (they do make ´em?) is IF?
Cheers
A

[93legendti]

Actually I like exactly the same position points of contact---same saddle height, same bar height, same everything---but with a slightly smaller or even small slope in the frame. ... 'Cross is waaaay more fun to me than mountain biking. I can stand the on and off stuff on 'cross but the falling over and fits and starts stuff of mtn biking has never appealed to me. To each his own!

get yourself the same size cross bike as yer road bike, and make sure it doesn't raise the bb to stupit [sic] heights,

dbrk

I agree 100%!!

[Bruce K]

Andreu;

There are lots of good choices for cyclocross frames without going custom.

Our own e-ritchie is one of the most respected cross frame builders. I wish I could wait for one of his myself.

I'm betting Dave Kirk's Terraplane would make a nice cross bike too.

The list of cross bike frames is quite long, Empella, Ridley, Red Line, Surly, Waterford, Cannondale, Trek, Fuji, Mongoose, etc. etc. etc.

Depending on your needs and wallet size you can go nuts or low budget and have lots of fun on a cross bike.

Given the weather report for Boston it looks like I'll be getting real muddy tonight shaking down my C'dale beercan for the start of the season.

BK

[Ken Robb]

an old steel bike with side pull brakes works surprisingly well for a non-racer slow guy like me. An old touring bike might even have canti brakes.
I'm not saying "just as good as a real cross bike". I'm suggesting a really cheap way to try it and see what you really want to get later.

[Ozz]

get yourself the same size cross bike as yer road bike, and make sure it doesn't raise the bb to stupit [sic] heights,

dbrk


please define "stupit heights"...

How does the geometry change on a cross bike from a road bike...or does it??

Stupitly yours,

Oz

[cpg]

In the old toe clip days, builders built cross specific frames with higher bb's for pedal clearance. Modern pedals don't stick out so far thereby increasing cornering clearance so bb's can be lower. I build cross bikes with 7cm of drop which gives enough clearance while allowing for good road handling characteristics. This gives the bike versatility.

[dbrk]

DBRK - any suggestions on a cyclocross frame builder - the only one I can find apart from Serotta (they do make ´em?) is IF?
Cheers
A

Carl Strong makes a cross bike both in signature sizes and custom and many are also happy with Brent Steelman's bikes. These are both custom shops if you need or prefer that.

The notion that a cross bike needs a bb higher than a road bike is a hold over from the era of clips'n'straps dragging about on mounts, dismounts, and obstacles. It is my understanding that certain great builders of renown (bikes with plenty of sachs [sic] appeal) build cross bikes with the same drops as their current road designs. One can expect to see longer chainstays, perhaps slacker angles, especially head tube angles, since the bike needs make abrupt climbs and handle solidly in the muck. What we see on most cross bikes are bb heights that only make the bike handle worse than it should---commonly less than 7cm of bb height! Yikes! Grant Petersen described this sort of high bb as a feeling akin to walking on stilts. With clipless pedals such a bb height is entirely unnecessary. So if Dario says 7 then 7 it is and if RS says 8 then 8 because it is the _whole_ design of the bike that makes it worthy and sublime---but go with someone who has a serious clue about the past and the innovations of the present. Not just anyone who builds knows about 'cross bikes, imho (anymore than they know about French randonneurs or whatever else is outside their realm!) The lugged Sachs 'cross bikes have proven themselves in serious international competition (Jonathan Page, et.al.) for the past so many years. There's a fella' who knows a thing or two.

dbrk

[e-RICHIE]

http://www.cyclocrossworld.com/Tech.cfm?Action=Edit&MenuKey=3&theKey=43&ShowDisabled=0



that says it all...
e-RICHIE

ps

:) :) :)
:rolleyes: :rolleyes: :rolleyes:
:p :p :p

arrange disorder

[Bruce K]

One of my favorite cycling sites !! :banana: :banana:

Stu has already given my beercan the once-over for the new cross season.

If you can't find the answer to your cross questions somewhere on this site, just call and ask. There is a huge amount of cross knowledge shared by the people who run Cyclocrossworld.com.

BK

[e-RICHIE]

BruceK wrote (snipped):
" There is a huge amount of cross knowledge shared by the people who run Cyclocrossworld.com."



don't forget to give attribution to the author!!!

[Bruce K]

mea culpa e-richie.

I assume you will be in Gloucester for the "double-header"? How about a beer or dinner when the dust settles or will you have too many bikes to maintain?

Are you guys staying at the Marina?

BK

[e-RICHIE]

BruceK-issimo wrote"
"mea culpa e-richie."


u silly!
i didn't mean me.
i meant the author of that seminal text, adam myerson, to whom
i owe nearly all of our success. without his interest, i may have
looked right past 'cross in 95/96 or whenever i began sponsoring
him. he knows more than most about this discipline.

e-RICHIE

ps

:D :D :D
:cool: :cool: :cool:
:) :) :)

arrange disorder

[Bruce K]

e-r;

You are way too modest. I know Adam wrote the article but look at all YOU have done for our sport and 'cross in particular.

If you are going to make Gloucester, please let me know. We live about 2.5 miles from the course so if you need anything.....

If the weather is really lousy and you need dry, warm workspace I have a small work space with a bike stand and some tools set up in our basement that you would be welcome to use.

On race day, if you are up early enough you can get a good laugh at the old, bald, fat guy in either the Mercury Brewing or ECV kit (that would be me) doing his damndest in the C Masters race.

BK

[jerk]

adam is the best. there is not a person more dedicated to our sport than him. he is also one fast bastard and a great coach. he has made the verge cyclocross series one of the best run race series in the area, the country and indeed the world. his sponsers get more recognition per dollar than any where else, his races are organized, his staff is great and the jerk just wishes he had half the drive this guy does.
jerk

[e-RICHIE]

jerk-issimo...

agreed!
adam was the most complete rider i ever sponsored,
and perhaps one of my best investments!
e-RICHIE

[KKevin]

I figured this was slightly related to cyclocross fit; Im curious about the choice of top tube down tube cable routing. What is the thought process for both. Im already thinking about the keeping the cables clean for top tube, then possibly the ease of build for down tube. What has anyone else heard?

[blifford]

my 'cross serotta was built using the data from my Ottrott fitting, just "converted" to cyclocross specs. I kept the stem length the same (I only use a 10cm anyway) and use the same handlebar and saddle. My bars are 44cm on the 'cross bike, though, when I use 42cm on the road bike.

Overall the bike is 1cm shorter in the top tube, the seat tube is 1cm shorter, and my head tube is 1cm taller. I honestly don't think that lowering the standover height was all that necessary... it's certainly never been a factor when I've been out 'crossing. My guess is the reason they lowered the standover height (by shortening the seat tube 1cm) was because the Ti tubes on my Concours cyclocross bike are considerably fatter that the tubes on my Ottrott.


I had them build it with a level top tube (even though a sloping tube would have kept my head tube extension from looking excessive), because I don't like the way the bike feels on my shoulder with a sloping tube. My bike is small enough (50 cm) and so if the tube slopes I don't have that much room for my arm and shoulder to fit through the frame.

I've been meaning to post a picture of both serottas... then you'll be able to see what I mean.

good luck and have fun in the cyclocross season!

cliffy

[cpg]

I figured this was slightly related to cyclocross fit; Im curious about the choice of top tube down tube cable routing. What is the thought process for both. Im already thinking about the keeping the cables clean for top tube, then possibly the ease of build for down tube. What has anyone else heard?

People have differing opinions about what's best regarding cable routing. Both routes work well so clearly there's no superior way. Neither routing is easier or harder to build.