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Toe Overlap & Jones index of stability


I try to make my perfect bikepolo geometry, can someone help me to check the toe overlap and index of stability on this design??



I need to have, at least an -2.97 jones’ Index

and my shoes are 300mm, with spd cleat at 95mm of the top! 

Thanks in advance! 

Toe overlap

I've opened the above design in BikeCAD Pro. I increased the shoe length to 300mm and set the centre of the cleat to 95mm from the front of the shoe. The image below shows the resulting toe overlap situation. The ISO 4210-2: Toe Clearance value is 129mm. The Jones Stability Criterion according to the formula from Bicycling Science 2nd Edition is: -2.999. Note that Bicycling Science 3rd edition presents a different formula for Jones Stability and downplays the importance of this criterion all together.

Thanks for your fast reply

Thanks for your fast reply Brent!!!
Do you have any other comments about this design?
Do you think I can reduce the Toe overlap without increase the stability?
And about the Jones' index what can I change to have -2.97?

I need to have the more handy geometry as possible with a great stability and especialy avoid the "tuck-under" or "oversteerer" effect when cornering at low speed
Maybe I can set the HT angle to 74?

I'm 6p1 and leg mesurment (C) is 35.8"

Thanks again

Jones Stability

I'm not encouraging you to put much stock in the Jones stability criterion, but if you are determined to achieve a value of -2.97 according to the formula from the Second Edition of Bicycling Science, you can do that by changing the head angle on your design from 73° to 73.13°.

I won't give any further advice on this model as I don't consider myself to be an expert on the design of polo bikes.

No, I know i don't put much

No, I know i don't put much stock on, I just rely on geometries of very good polo bike, and both used this value.

But thank you for your help, it's much appreciated! 

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