Waydoo Upgrade Kit

I installed it on a Waydoo Flyer One that I bought last summer. It dramatically reduces the noise from the motor - it takes the noise down from a noticeable whine down to a very quiet hum that is substantially quieter. I saw a "gear" decrease - I could foil on "gear" 8 - which is down from gear 11 on the old prop. I also saw a substantial improvement in ride time. I was riding on the patroller wing tonight and I went from a previous average ride time of ~50 minutes up to a ride time tonight of 71 minutes - but I still had two bars when I was done. In terms of distance, I usually ride ~13km (8 miles) per ride and tonight I rode 19.1km (11.8 miles). So I rode longer but I was also riding faster. I weigh 68kg (150lbs). I played around with speed near the end and I also rode the fastest that I've ever gone - I hit 38kph (23mph). I noticed that I didn't go any faster after I got to gear 18. 19 and 20 made no difference although there was a weird noise on gear 20 so I gave up and went back down to gear 16 which had me moving around at 31kph (19mph). One of my friends is closer to 90kg (200lbs) and for him, the noise reduction was the same but he didn't see the longer ride times that I saw under the same conditions so the efficiency improvement seems to be weight dependent.