Get'n Passed by EVERYONE!


(2 RollingStoned) #1

On dumb Kurt Kinetic Road Machine (with optional heavy flywheel) with Garmin speed/cadence/heart sensors. Haven’t ever used a power meter so don’t know where my data fits with reality but at 95% of max heart rate I’m seeing 125-150 with the virtual power. 5-7% climbs I’m seeing 3mph! I get passed by everyone at often blistering speeds, uphill/flats/downhill, doesn’t matter. I dropped my weight from 180# to 165# with little effect. Is everyone riding at 90#??? Not much fun when I can’t even hold a wheel on the slower riders when I’m maxed out. Help!


(Eric C. (Zwift HQ)) #2

Hi Steve,

We don’t support the heavyweight fly-wheel at the moment so that is the #1 red flag for me and the most likely reason your wattage is way off.


(Clint Westhoff) #3

The flywheel weight doesn’t affect the KK power curve and should not affect overall power numbers very much, except to the extent your “jump” requires a bit more power to spin up the flywheel and may feel like it makes your legs tired (but that energy is stored in the flywheel which is why the heavier flywheel takes longer to spin down - you can’t lose energy - 1st law of thermodynamics).  The flywheel weight takes slightly more energy to spin up but will spin longer, but the power curve is the same for a 12lb or 6lb flywheel so won’t make the wattage way off.  


(2 RollingStoned) #4

Thanks for both comments. The proof will be in the pudding, I will test without the flywheel and report back.


(. EZRIDER) #5

I had the same problem with a Giant Cycotron Fluid trainer. i put in as a classic and could not keep up. i put it in as a Blackburn fluid trainer witch is on the list and now it’s like night and day. i hope that helps someone…i hope they put more trainers on the list soon…


(2 RollingStoned) #6

Interesting suggestion Tim. I’m traveling until next week so won’t be able to test without the heavy flywheel til then. My KK Road Machine is supported by Zwift but putting it in as another type may be the answer if the flywheel isn’t.


(. EZRIDER) #7

Yes keep in touch and let me know. thanks


(Eric C. (Zwift HQ)) #8

FYI: putting in a different trainer means you are using a power curve that is NOT written for your trainer so your wattage and data could be all over the place and not accurate.


(2 RollingStoned) #9

OP Follow up:  Ok, I’ve had some time to experiment and have found a slight improvement by taking the heavy flywheel off. Slightly better acceleration response in Zwift as one would expect. Too bad though because you lose the slight coasting advantage. In the end I had to drop my weight from 180 true to 125 (not true!) in order to get Zwift road speed to roughly correlate with reality. And now I’m having fun drafting, dropping, and sprinting with other riders. BTW, I’m still getting hammered by most which still has me scratching my head. For example, how do the top riders go 33 mph up 7-8% grades? Anyway, I’m happy to be in the game at this point. Last thought: I’ve never run a true trainer tire, I just waste away old road tires. Is that the missing link?


(Steve Lovell RaceWBR) #10

Not a cheap option (but getting more affordable)

I use the KK rock and roll trainer with a power meter you then get the best of both worlds.

A quiet trainer with a good road feel and real power that you can also use out on the road.