Lewis_Moon

OK, this is NOT a No0b question...really. I raced for around 18 years starting back in the mid '70s and quit for a a long while and I'm just starting to road ride again. The problem is, I couldn't remember how I liked my road bike set up. I went to a website and found the 109% formula to get into the ball park. When I hopped on I felt like I was on stilts...well, stilt. My butt was rocking and my knees were locking. It dawned on me that my Mt. bike was set up a lot like a road bike (you can't take the road out of the roadie) so I measured it and it was a full seven cm shorter than the 109% "rule".
I picked up a low heel riding style when I was younger and my leg doesn't come close to locking....have I been doing it wrong all along?

Campag4life

Not weird at all. I personally believe the 109% rule or even Lemond formula of .883x inseam is bit high for the recreational rider with limited hip flexibility. So many factors...you mention a big one...you rode off road for years and are conditioned to ride with a lower saddle. But technique is big...whether you ride toe down...how big/long your feet are...cleat stack height...lots of factors. I also ride with a low saddle height relative to my long inseam of 35"....a full 1-2cm underneath both formulas. You need to find the right saddle height for 'you'...and it won't necessarily comport with a formula...formulas are based upon models and models don't agree with everybody.
For me this comes down to how clean my pedal stroke is and whether I feel my quads are doing too much work if the saddle is too low and if I feel a slight twinge in the back of leg at knee level if the saddle is too high and I am over extending.

Lewis_Moon

I never could lower my saddle on my Mt. bike much. I like to hammer on fire roads and never much got into the technical or downhill, so my saddle height is probably somewhere in the same range as my road saddle height. I figure since I'll be riding look pedals the seat height will come up ~1cm but, even if you add a cm or two to that to compensate for the Mt. bike conversion, it still puts me 4cm lower. When I was racing we always used the "sit on the bike and pedal backwards with your heels on the pedals" method. My inseam is 37" (94cm), and given the usual rule that there is more variability the farther out on the tail of the curve you get, I'm probably not so far off.
I'll probably ride with an allen wrench in my pocket for a couple of weeks till it feels correct. I've been completely out of the saddle for years, so it'll probably take a bit before it's dialed in.

StanSeven

No, if your butt is rocking that's a sign the seat is too high. If you leg doesn't come close to locking, you have limited flexibility from years of riding that way. You'rte got two choices - keep the position you are most comfortable with but perhaps not gaining mex power/efficiency or try and gradually increase your seat position over time. If you do the latter, I wouldn't increase it by more than 1 cm at a time.

Lewis_Moon

Here's a question: If you use the afore mentioned "sit on the bike and pedal backwards with your heels on the pedals" method, how would you ever reach 109% w/o some butt rocking? 109 % of my inseam is over 3.5" longer than my leg. You couldn't hold your heel on the pedal at that length.
This was the method that was in vogue when I was riding hard. The pedaling style was also that you had a level foot on pretty much all but the "pull" section of the stroke.

StanSeven

Put your foot on the ground and lift your heel keeping the ball touching. You should easily get more than 3.5 inches of space.

ahsposo 

Also bear in mind that saddle setback is an important part of this adjustment too.

Lewis_Moon

Easily. I have a big foot....but I was always taught to have a level foot through (most of) the pedal stroke and that "ankling" was bad.

FrenchFit 

It's time, or lack of time, in the saddle. From zero to almost daily riding over the last 4 years my saddle height has gone up 2-3 inches depending on the bike. I'll leave it to a doctor to explain why.

ericm979

How are you measuring the 109%?

ColinL

3" is huge! improvements in flexibility and a poor initial fit sounds more likely to me than suddenly being able to reach 3" farther on the downstroke.

FWIW (probably nothing), I am very near Lemond's 88.3% of cycling inseam on my road bike, about 6mm above it.. How did I get there? Lots of experimentation. I'm 35mm lower on my MTB as a compromise between pedaling efficiency and having enough clearance out of saddle for bumps and drops.

Lewis_Moon

Center of pedal spindle to top of seat. With Sterrett rule w/90 degree attachment from the same company. Dad was a machinist.

bored117 

Also you are probably not as flexible...