TimJ

I'm having a hell of a time trying to get my cx bike to fit me. Here's an out of date photo for reference:

https://www.flickr.com/photos/timrose...7594546525758/

Basically I just haven't been able to get it to fit right. I took a ride a couple weeks ago and when I got to my destination (only 5 miles away- but uphill the whole way) my back was seizing up and I had to lay on a bench for 20 minutes to keep from blowing it out completely. I changed some stuff around and thought I got it better but I took the same ride a couple days ago and my shoulders and neck were killing me. I changed it a little more and this morning rode it to work- little better, but my knees hurt and my butt was uncomfortable. I've got a vintage bike I ride fixed and a rigid mountainbike I both ride fairly often and I don't have any problems with them. This bike... cripes. I get one thing feeling OK and something else craps out.

So I've been looking at bike fit strategies and I figured I'd try to start w/ a traditional road bike fit. But you know that thing where the bone below your kneecap is supposed to bisect the pedal spindle when the cranks are parallel to the ground? That's simply impossible to acheive on my bike with the seatpost up high enough to give me proper leg extention. If I push the seat all the way forward on the rails that bone is still a couple centimeters behind the pedal. So I wonder if the bike isn't too small for me... or something.

In the photo the seat is about where I usually have it height-wise. My knees are pretty far back from the spindles. Right there I can't start from a traditional fitting stand point. And it feels like I'm too far back, my legs are reaching forward too much. If I push the seat further forward I get too close to the cockpit and a longer stem (which I had on there the other day) doesn't help because the handling gets funky.

So I don't know what other angle to approach this from. right now I have a stem converter and a... 100mm stem (I think) on there. It feels pretty good but my knees hurt, like I said, and for some reason my seat- the same seat I use for my mtb and love, feels too narrow and my butt waddles up and down on it, even though it's not up too high.

See, I'm a mess. Any tips?

vanwaCX

Picture with you on the bike perhaps? Even then, internet advice is what you pay for it. Best bet would be some video of you pedaling. Do you have a point and shoot, a trainer or rollers, and a reasonably fast internet connection? If so, you can shoot some video on the point and shoot, then upload it to YouTube, and show us what you look like.

TimJ

I'll see if I can summon the moxie to do that.

I just don't know where to start. I did some more futzing with the seat and it feels pretty good now but the seat itself feels like crap, which is weird because I love that seat. It feels narrow and my hips are rocking.

Junkdad

start with your heal touching the pedal, and no hip rocking.

spin a low gear

see peter white's article

https://www.peterwhitecycles.com/fitting.htm

idcruiserman

Nice looking bike. I would rotate your bars up a bit to get them flat the top. Point the end of the bars at your rear brake for a guide.

If the bike doesn't fit, sell it, and get something else.

TimJ

I'll get some pics up tomorrow. Assuming I don't revert to my lazy ways.

TimJ

OK here's some photos. The bike feels better now, I basically have the saddle all the way forward on the rails and that's a 100mm stem. But the seat still feels weird, and this is a seat I love -- I have it on my mtb and on my fixie until I got my brooks. It feels like my hips are rocking- like my butt is rocking- but I'm not overextended. I've always used the "heel barely touches the pedal when in line w/ the seattube" rule of thumb and it's always worked for me, this bike though, something is always off. Right now it's the seating.

I think it's too small for me. I'm 6' and it's a 54, my fixie is a 58, I suppose maybe the smallest I should go is 56. But it's weird because I have to have the seat pushed all the way forward in order for it to feel OK. I guess if it were a bigger frame the seatpost wouldn't be up as high and therefore not as far back. I dunno. I'm gonna race this sucker this year no matter what.

Whaddaya'll think?

idcruiserman

IMO it's too small for you.

jbpence

I'm 5'10, and my cross bike is a 54. your photos seem to indicate your bike is too small. i agree, you are not overextended. you look cramped. IE, reach too short. I know you think its feels like a lot of reach, but you dont look like you have too much, you look like not enough reach to me. also, with the ball of your foot over the pedal spindal, does a plumbob hung from the front of your knee 'point' to the spindle? it looks to me like your knee is too far front (a pict in the three o'clock pedal position might be revealing). if your knee is forward of your sindle at 3 o'clock, its gonna start hurting - and means the frame is too small. get that seat set so your knee is in the correct position when pedal is at three oclock, if reach is wrong then, adjust the stem length. if unable to get correct reach, frame is too small. bad idea to set reach by pulling the seat forward.

TimJ

No, as I've said my knees are actually behind the pedal spindle unless the seat's all the way forward- which it is now. I'm not setting reach with the seat, I'm trying to get my knees forward because too far back they hurt. I think it's just too small regardless of the individual problems that crop up.

jbpence

oops, sorry I didn't fully understand your earlier post. I see you tried a longer stem but didn't like the handling - how long was it (I use a 120cm, thats pretty longish, and I dont notice any handing difficulties.

as an aside, dropping from a 58 road bike that fits fine to a 54 cross bike seems.... like too small. SOme (not all ) folks like to frop one bike size between their roadie and cross biokes becuase the bottom bracket is typically higher (or so I've read) . you dropped a whole 4 cm in seat post length. I know if I went from my 54 cm roadie to a 50cm cross, I'd never get it to fit.

TimJ

I bought the thing not knowing exactly what size it was, and before I knew really what was too big or too small for me in road/cyclocross bikes. The longer stem is 110, the shorter 100, and the centimeter makes a pretty big difference. W/ the 100mm stem it feels basically good but a little cramped, the longer stem just feels like crap no matter what. I think a 105 or 100 w/ no rise might work, but it seems real odd that a mere centimeter would so completely throw things off.

i_r_beej

First thing I noticed is that your stem seems too long. In the photo your elbows appear locked. On the hoods, you should be able to relax a little and not feel like your reaching waayyyy out there.

You don't want a stem with no rise-- that would drop your torso farther down and definitely kill your lower back. If anything I think you need a stem with MORE rise. It looks like you have a 5-deg, maybe 10-deg stem on there in the photo.

The bike *might* be a little small for you. A little. Too small? I don't think so-- but that's just my opinion.


I'd suggest that you try to find a bike fit specialist-- many good bike shops offer this service. They generally take about an hour and may cost about $100 to $150. Money well spent.

flargle

Bikefitting "service": overrated. Do you think bike shop employees would be there if they had other options?

The information is out there.

jbpence

+1 though I think this is an over generalization: many (but by NOT all) shops are super crappy even though they seem to do a complete fitting. some shops do a great fitting service and get it right the first time with no fuss. Its worth paying for when they know what they are doing. And its a total rip off when you are charged by a shop that is incompetent for a fit that is not good

TimJ

Alright, you got me all upside down now.

OK, here's the biggest weird thing that makes me think it's too small: unless I push the seat all the way forward on the rails my knees hurt because they're so far behind the pedals. I've read different fit schemes and people say the whole "bone below the knee bisect pedal" is just a more-or-less arbitrary rule-of-thumb, but the fact that it is a rule of thumb, arbitrary or not, makes me believe that a properly sized bike will probably have a position on it- correct saddle height and all- in which your knee can/will bisect the pedal spindle. On this bike it's impossible. You can see in the photos- though you have to look at the leg on the opposite side of the bike- that that little bone is still pretty far behind the pedal spindle. My thinking is it's because I have to have the seat up high, that pulls the seat back, etc.

OK, so I rode it again last night and again w/ the saddle anywhere but completely forward it's a killer. W/ the seat completely forward I feel a bit cramped. I want to go back further but can't. But a longer stem (110 w about 7 degree rise is what I have) doesn't feel right no matter what I do. W/ the 100mm stem it feels OK but cramped a little, and actually I feel like I want to lower it a bit. What you're saying is the bars should be up and back a little more? I dunno. It just feels weird with the bars up so high already- and in that photo I don't feel stretched out at all.

Cripes! I've been trying to look for photos of happy, comfortable people riding their cyclocross bikes, but haven't had luck yet w/ just regular sit-down side views.

In regards to bike fit service- I don't trust any lbs that's near me, so...

isotopesope

tim,
i've been going through a similar fit ordeal as you with my cyclocross bike. i got a sweet deal through a friend at colorado cyclist on a complete douglas cross bike with upgrades. at the purchase point, i think i had been riding slightly too small of bikes, slightly too low of seat, and didn't have a decent enough understanding of fit in general. not that i know much even now, but at least i have a better idea how to feel more comfortable... anyways, i thought the 59 c-c seat tube and top tube would be perfect. well, the bike is too damn small ultimately. i'm 6'4" with a 36" inseam. my road and track bikes have 61 c-c seat tubes with 59 c-c top tubes. they fit me well, but really i think a 62 would be even better.

so, i initially rode it as it was built, with the 6 degree 120mm stem flipped down and low on the steerer. it was killing my back, neck, and wrists. for TWO YEARS i've been wrestling with it, never feeling right. i raised the stem to various heights, flipped it up and down, changed my hood positions, my bar tilt, my saddle height and it's forward/back position, etc. dozens of times in hundreds of combinations. every time it would feel better sitting on it, until i went for decent length ride... and would find it still fit like crap. i tried several online calculators, but they made my bike fit too aggressively, leaving me too stretched or reaching too far. several iterations would last months, but i still knew something wasn't right.

ultimately, i just felt too scretched out. in my mind i think i was really only considering the cockpit length almost the entire time. i was straight arming it and felt like pushing my saddle all the way toward the stem and running a shorter stem would relax my arms. nope. the bars were just too damn low. so, now i have a new fork with a slightly taller steerer (i would've left it even longer had i seen the light before cutting it), close to two inches of spacers, and a 120mm 17 degree stem flipped upward. it looks sort of goofy, but the bike fits me sooo much better and feels comfortable after really long rides. i don't have a current photo, but my bars and saddle are nearly level, and my saddle is about mid-way in the rails of my zero setback seatpost. the bike is still too small, but now i can ride it without pains.

TimJ

Hmmm.

Hmmmmmmmm.

And you've been racing this bike? If not, how have you been using it?

i_r_beej

Sorry about that. Unfortunately bike fit isn't really something that you can do "by the numbers." The best advice I've found is that you need to experiment and have the bike fit you. Having someone (bike fit specialist) make a few adjustments and position you to fit the bike according so some formulas is not the way to go.

Sure, there are some good "rules of thumb" to get you in the ball park. "KOPS" Knee Over Pedal Spindle, for one.

However, as with most troubleshooting-- and adjustments-- focus on one thing at a time. If you go and adjust several things at once it will be impossible to determine which one is working or causing problems.

Just from looking at your side-view photo, I'd recommend that you go get a 35-degree stem. If you've got a 100mm extension currently, keep that. But remember-- the steeper the angle, the less reach you'll get. For instance, at 35-40 degrees, a 100mm extension translates to about 80mm horizontal reach.

Last winter I went through a similar experience. I have a small collection of stems to prove it. Anyway-- I was still feeling a little low and short.

One of my LBS has a decent rep and a 1 year guarantee on fittings. I went in and came out with my saddle a little farther forward and a stem that was 10mm longer and 15 degrees higher. So after all my fiddling I was in the ballpark.

You might want to check this out.
https://www.bikefittingkit.com/

While the kit is apparently targeted at road bike set-up, I think that it would serve for setting up a CX bike-- maybe just compensate by bringing your handlebars up higher.

Good luck.

isotopesope

i use my cross bike as my main do everything bike. it's my commuter, my back up road bike, a mountain road explorer/light single track, etc. but i don't race 'cross... yet. i feel confident i could race it with this position though.

i really want to try racing cross, especially after coming off of track season fitness, but i haven't been racing track really at all this season either. lately, mountain biking and other lifely duties have been far more important to me than racing.

TimJ

Well both of you are saying the same thing basically, higher stem, so I might as well give it a hot. I'd like for this bike to work out, I got it NOS last year and haven't got it running till pretty recently and now it seems too small. I've been a sad man. So another $15 on a cheap stem to see if it works, I suppose.

vanwaCX

It's a cool retro bike and it would be great if it fit you. Even though you've got a long torso compared to leg length, I think you'd be happier on something like a 56. Your best bet would be to attempt to match the top tube length of your road or track bikes. I like a 55 cm top tube on the road and 54.5 cm top tubes work best for me for cross. The half cm difference plus geometry makes me sit up a bit higher on the cross bike.

I rode a bike that was too small for me for a season. I did okay. I bought a race bike that was the right size the next year. During a race, I finally needed the pit bike -- the too small bike. I couldn't believe how terrible it felt to ride. I promptly sold the frame and bought one of the proper size.

Do yourself a favor and get the right size.

Even if you don't want to shop at your local LBSs, see if you can test ride a couple of cross bikes in different sizes so you can get an approximation of what works for you.

isotopesope

so i just got home and took a photo of my bike:

as you can see, the bars are maybe two inches lower than the saddle. imagine where the bars would be with a 6 degree... i also have the hoods closer; before i had them right at the edge of the reach, making my arms have to reach that much further.

flargle

Horizontal top tube with that much seat post showing.

TimJ

I'll give it a shot. Thanks for the pic.