I changed the bike to a cheap hybrid and switched over the kit.
The forks weren't the only reason for changing. My old single speed racer was perfect for my old road only commute in London, but a bigger hybrid with straight handlebars and wider tyres is much more suited to my new mainly coastal path commute.
I chose this particular bike, mainly because it was £200, in stock near me, and seemed acceptable quality. But its been surprisingly alright:
http://www.halfords.com/cycling/bikes/hybrid-bikes-and-classic-bikes/raleigh-edale-mens-hybrid-bike (largest frame, I'm 6ft1)
Steel forks, and the drops didn't need to be filed to fit - checked this by taking the wheel into the shop before buying. Generally seems more suitable for an electric conversion. Much more comfortable and stable. I've been leaving it in top gear permanently.
Have now done 100 miles on the new bike. Including my 26 mile total commute today. It was quicker than by car, and much more fun.
Throttle only it does about 18mph on the flat with no wind, and has a 25 mile range on my route being used in that way. I've run it throttle only for most of the time so far, as you're supposed to fully discharge then charge the battery 3 times before part charging and I wanted to do that as quickly as possible.
But I won't use it throttle only day to day. I'd prefer to pedal lightly most of the time, and put in some effort to move quickly on smooth open sections when they're quiet. Seems there's little (but some) help from the motor in these bursts. Rare opportunities but I've been up to about 25mph according to my phone (or 35 according to Strava, suspect the former is more likely).
In most situations, the motor is very quiet but its whir will be noticeable to those around you on throttle only. Only gets a little brash on steep hills.
The kit feels pretty strong to me. Particularly when fully charged. There seems to be a very gradual drop in power throughout the battery's discharge. The flat cruising speed appears to drop from 18mph to 15mph over the full range and acceleration drops proportionally. The battery range is so much further than my point to point journey this won't affect me, but I'm glad I didn't go for the smallest battery option.
Loving the kit, and my new commute. Very happy with my new electric bike.
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