Yep, me too. Night and day for me.

Hi,

Last winter I had a Retul bike fit and for the new season I want to tweak my position a bit.
I wont change much overall but would like to set my cleat position about 3 or 4 mm more backward (now 7 mm behind ball of foot, to 10/11 mm behind ball of foot). Obviously I need to lower my saddle height (therefore also setback) to compensate.
Not planning on doing another Retul fit just for this as this costs money.

I know it's a long shot, but maybe some fit experts here can help:
Is it safe to say that when I set my cleats 4 mm backwards, my saddle has to lower 4 mm as well? Or is it not that simple?

Thanks,

roselend.

Could you not move your saddle 4mm forward?

It's not a 1:1 ratio.

I'll see if I can find the literature around it...

_________________
Baum Ristretto, Baum Mondrian Corretto & the '89 Merckx! | "If you could eat it in one sitting, hold your line." | twitter.com/Tinea_Pedis

There isn't a ratio- it depends on how much more your heel drop and extension changes. Your ankle and knee angles might not change a whole lot with just 4mm, but I recently moved my cleats back about 15mm and had to move my seat forward about 7 to obtain similar angles.

Steve Hogg would beg to differ.

_________________
Baum Ristretto, Baum Mondrian Corretto & the '89 Merckx! | "If you could eat it in one sitting, hold your line." | twitter.com/Tinea_Pedis

Weird because I asked the question on his website and posted his response here almost exactly. He even writes that there are no formulas, but that with every change one should re-asses the key metrics used for proper saddle height and setback.

Link?

I read it a year or so ago, for every x of set back he recommended y of change.

The beauty of Steve is that he's happy to change his mind and go back on what he's said previously if he's found it doesn't work.

_________________
Baum Ristretto, Baum Mondrian Corretto & the '89 Merckx! | "If you could eat it in one sitting, hold your line." | twitter.com/Tinea_Pedis

Well, I dug deep in the internets and all I came up with is this:

Link: http://www.stevehoggbikefitting.com/blog/2011/04/power-to-the-pedal-cleat-position/


But I did come up with this regarding saddle fore-aft/height (probably the bit Tinea was talking about). Comes in pretty handy because I'm putting the saddle a bit more backwards to.

Link: http://www.stevehoggbikefitting.com/blog/2011/09/all-about-smps/

Slightly off-topic, but I always seem to forget how much valuable information Steve Hoggs website has..
For example, instructions on changing seats at the bottom of the post: http://www.stevehoggbikefitting.com/blog/2011/09/all-about-smps/
Figured this out by myself already but he explains it very well.

Isn't this just basic geometry ?
If your seat tube angle is 73°, then (90-73) = 17°
The Tangent of 17° is .306

So if you move the seat back (horizontally) by 3mm, you would need to also move it down by 3mm*.306 = .918mm, which is approximately the 1:3 ratio cited by Hogg.

If your frame has some other geometry, you could plug in those numbers.

And another here.

As an update, I'm feeling much better on the bike with my cleats setup for the ball to be 9mm in front of the pedal axis and I'm going to put on the adapter plates to move them even a tad further back. Not mid-foot, but still my peak power and jump in a sprint hasn't diminished and my output is higher/more constant.

roselend, there is that ratio. However when I had a fit with Steve and in his dealings with us, if a customer is truly running their cleats decently setback then there are geometry considerations he makes when putting together their custom geo for Baum to build.


KW, you wouldn't notice a difference in your sprint. From what Steve again has said, you would need to be pushing about double the amount of setback that you have to possibly start lacking some kick in the sprint. Flip side though would be you should be even more efficient in holding a 5min power (so might not need the sprint )

_________________
Baum Ristretto, Baum Mondrian Corretto & the '89 Merckx! | "If you could eat it in one sitting, hold your line." | twitter.com/Tinea_Pedis

Tinea- do you work for Baum now?

To everyone else- I highly recommend that you do each shoe separately and also measure the distance from your heel to first metarasal. My right foot is almost a full cm shorter than my left, which made a big difference in setup.