I recently got a kickr2018. Before this, I had a Lemond Revolution. I was doing Petit today which includes some form sprints. I was in a 50x19 using ERG mode.
I dropped my cadence to around 85 just before the sprint (which is 10 seconds long). Then, hopped out of the saddle and wound up to about 170 rpm before sitting down and hammering out the rest of the sprint. Not sure where I lost my form but pedalling was a little bumpy (not smooth) from a certain cadence (max was 184 which not sure its 100% accurate but anyway, was pedalling fast).
After losing control of the sprint cadence wise, it took what seemed like an age for the fly wheel to slow down to give me back power at a reasonable cadence. I’m guessing that I should try using 34x21 or something instead of the big ring for form sprints now with ERG mode to combat this as this would generate less fly wheel speed?
Am also thinking that those two form sprints that I did were not successful in that it would be better to keep smooth control during the complete sprint but I guess the power requirement was so light once the speed went up in ERG mode that it just let me spin like a mad man. Will see what a lower gear yields.
Interested to hear some feedback in the meantime on how others have addressed this.