Determining the Rear Tire Reaction

Use Weight Distribution Simulation II below to help you with the exercises on this page.

The activity on this page, Weight Distribution II, is similar to Weight Distribution I but now the virtual bathroom scale under the rear tire has been removed. A text box and two buttons have been added which allow you to check your calculation of the rear tire reaction or to display the actual rear tire reaction.

Apply various amounts of weight to the seat, handlebars, and pedals. Based on the reading of the front tire reaction, calculate and enter the rear tire reaction for each case. You can check your answer with the SUBMIT button. If you want to display the rear tire reaction, use the ANSWER button.

During normal riding your weight might be distributed as follows, 150 lb on seat, 25 lb on pedals, 10 lb on handlebars. Calculate and verify the rear tire reaction. Now suppose that you encountered a hill and were in a "climbing" position such that you now had 20 lb on seat, 125 lb on pedals, 40 lb on handlebars. Recalculate the rear tire reaction.

Was there a difference between the rear tire reaction due to the way that the forces were distributed during normal riding vs. climbing? You should find that even though the total weight is the same in the two cases, the way that it is distributed between the front and rear tires is different. What phenomenon might account for the changes? What might happen to the bike if somehow the tire reactions for normal riding occurred while the weight was distributed like the climbing case? While a complete explanation will be deferred until later in the module, submit your impressions at this point.


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