bssjackson

Wondering if thats a myth or fact?

urbanknight

Depends on where you're looking from. If you're referring to the statement that while in your hoods on the bike, the handebar should hide the front axle, that's a general guideline. It's not exact, and even then you might just need to move your saddle or get a different size stem.

JayC

With all the varying geometries, I dont think this really holds true anymore.

ManBearPig

It usually works out that when fitted properly, the front axle will be at least slightly obscured by the bars in your line of sight, while on the hoods (not on the drops or any other position). Here's my theory. This rule and other rules like the KOPS rule (knee over pedal spindle) are not the objective of a good fit, they just happen to occur when the fit is good. In other words, there is no direct benefit to the knee being above the axle, nor the bars being aligned with axle in your line of sight, but when the fit is right they are usually true. I think this is the consequence of the fact that all road bikes have the same basic shape and design. Yeah, there are traditionals and compacts, and custom geometry, but if you look at and compare all bikes they all put the wheels, seat, pedals, and bars in about the same relative position to one another. So, it's just an observation that most of the time these rules hold up. It just works out that way. That's my theory.

johnny99

I disagree. This "rule of thumb" has nothing to do with geometry. It mostly deals with the distance between your saddle and handlebar, which should be the same in any geometry. Also, it mostly tells you if your stem is the right size, not if your bike is the right size.

Clevor

I had to do a doubletake myself, but I checked: your handlebar should obscure your front hub with your hands in the DROPS, not hoods (just checked the CC website). Generally, with hand on top the bar, the hub should be behind the bar; with hands on hoods, the bar should partially obscure the hub; with hand in the drops, the bar should obscure the hub. I've seen this bit mentioned on all the bike fitting articles in Bicycling Mag over the years, and it's also mentioned on the Giant web site.

However I don't use this as my first criteria for correct fit (as a knee jerk reaction). I fit everything else first and check this last. Darn if it isn't correct on all my 4-5 ATB and road bikes. I suspect many recreational riders use too short a stem or TT; you'd lose power if you were racing and you had to go ball's out. On ATB bikes, the bar should obscure the front hub with hands on the bar, of course.

Things you should check first is your saddle position with knee over the pedals at 3 o'clock (that plumb bob deal). Adjust the stem so the elbows are slightly bent with hands on the hoods, back as straight as possible. With hands in the drops, there should be at least 1 cm clearance between your elbow and knee with knee at 3 o'clock. It would be nice if the tip of your shoe clears the front tire on turns (but this varies depending on the frame). Then finally, check the bar/hub bit to see if it pans out. Works for me everytime.

Nessism

Wonder if Sean Kelly and Indurain knew about this.

atomsuite

I agree with the geometry affecting this guideline. I have road bikes and track bikes. Could be the setup of the track bikes more than the geometry so maybe I should rephrase my disagreement by suggesting the use of the bike affects the guideline.

Psimet2001 

I find it is an appropriate technique for determining the appropriate stem size...not bike fit. I have used that technique with many riders over a lot of years.

As with all rules of thumb it is only good if it works for you. Only riding will tell you that.

nitropowered

Its a general rule of thumb that works for most recreational riders. For more competitive riders, i'd say the its at best a starting point but plan on changing out stems a lot to see what feels best. Most bike shops should have a bunch of stems of varying lengths that you can try out to see whats best.

Salsa's Size-o-matic stem is really nice to see what you want but the downside is its a trainer only rig. Can't go out and ride it (and wouldn't because if you ever used one, you'll know how flexy it is.)

oilman_15106

Myth.

hiromian

A bent fork throws the rule of thumb off a bit I find the rule to be true enouph for my bikes.

Proximo

Depends entirely on how much you bend your back when riding and whether you are consistent about it. I'm not so sometimes I see the hub and sometimes I don't.

Ernesto Schwein

Tell that to Ballan:

https://www.cyclingnews.com/tech/2007...allan_wilier07

kls1891

+1

That's what I've always heard as well. Drops, not hoods.

DocRay

Yep, drops, never hoods. Typical BF thread, tons of authoritative answers, completely wrong.

bdcheung

Erm, if I shift up on my saddle, I can see the hub again. Does this mean my bike doesn't fit when I scoot forward because my butt is tired?

ggg300

The thing is a starting point at best...I got two bikes...one track...one road...

On the track I can see hub and then bars...on the road bike my see bars then a bit of hub...

The question is really about fit...and you'll get a ton of authoritative answers, some completely different.

https://web.archive.org/web/199802010...Debunking.html
https://www.peterwhitecycles.com/fitting.htm

Psimet2001 

Yes. If your bike fit then your butt wouldn't get tired. Duh....

cyclezen

bike too big/too small? this gives no indication
'myth' ? yes, if used to 'decide' on some frame size/specs

'rule of thumb' for stem length? works for some and doesn't work for an equal number of others

for about 5 yrs, when I first started ridin to race, this 'rule of thumb' kept me from getting to a good position
some rules are definitely meant to be broken.