Daymak / Shadow
- Thread starter Jerome Daoust
- Start date
John in CR
100 TW
Interesting bike. I'd love to get one apart to see how they address the issue of heat and durability of the batteries having both motors and batteries in the wheels. It's really nice and simple looking, though I don't understand the rationale of putting batteries in the wheels, which Tidal Force does too. At least they put the swing arm pivot at the crank, because it baffles me why it would be anywhere else on any bike. Regarding that 115km range, all I can say is not with me on it. Cool bike, and I'm sure many others are in the pipeline too, though probably not too many that can claim tackling 30° inclines, and probably not too many with 2wd.
John
John
northernmike
10 kW
If the quality is like their older scooter style ebikes, expect about a 12 month service life!
johnrobholmes
10 MW
The pivot at the BB will cause suspension dive when pedaling.
I don't know why the batteries are put in the wheels either. I wouldn't want so much rotational inertia, but at least the stealth factor is cool.
I don't know why the batteries are put in the wheels either. I wouldn't want so much rotational inertia, but at least the stealth factor is cool.
Link
1 MW
johnrobholmes said:
I really doubt the batteries are spinning along with the wheel. Major issues with that. Like how they'd hold up to the the G-forces and that you'd need a brush system to get power out of them.
And yeah, stealth and possibly a low CoG are the only things in favor of in-wheel batteries. Admittedly, that level of stealth is nice.
Regarding the bike up there: Nice. Don't really care for the yellow, though...
i'm sorry, i have difficulty believing their performance claims.
if both wheels were full of nothing but battery u might get 115 km range.
having to share precious real-estate with a motor yet, it defies physical limits.
as usual, they don't specify @ what speed, must be mostly pedaling too.
i'd have given it considerable benefit of doubt cuz u just never know.
but the last bit about portable solar charging put it over the top for me.
Like with the Schwinn electrics, expect the figures to come down to reality once in production.
if both wheels were full of nothing but battery u might get 115 km range.
having to share precious real-estate with a motor yet, it defies physical limits.
as usual, they don't specify @ what speed, must be mostly pedaling too.
i'd have given it considerable benefit of doubt cuz u just never know.
but the last bit about portable solar charging put it over the top for me.
Like with the Schwinn electrics, expect the figures to come down to reality once in production.
A
Anonymous
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John in CR
100 TW
Miles said:
I find it difficult to believe that moving the pivot point a few inches away from the crank magically cures this effect. I think getting it away from the crank is mostly about easier chain routing.
John
johnrobholmes
10 MW
Link, Not rotating batteries, duh! Don't know what I was thinking. Still not a good place for weight IMO, but it works.
That is correct. If the BB is on the swingarm fully then the only leverage will be in respect to the anti-squat characteristics of the suspension. Swingarm mounted BB cause other issues like a stiffening of the suspension when you get out of the saddle. The other method of canceling out chain torque is to locate the pivot in line with the chain. Of course when you have multi gears on the bike it is not possible to get it perfect all of the time, as the chain line will change for each gear.
The best method I have seen are the downhill gearbox bikes, where the pivot and the front sprocket are mounted at virtually the same point like a motorcycle. There will still be normal anti-squat characteristics under acceleration, but the chain line is so close to the pivot line that pedaling torque on the suspension is minimal.
gogo said:
That is correct. If the BB is on the swingarm fully then the only leverage will be in respect to the anti-squat characteristics of the suspension. Swingarm mounted BB cause other issues like a stiffening of the suspension when you get out of the saddle. The other method of canceling out chain torque is to locate the pivot in line with the chain. Of course when you have multi gears on the bike it is not possible to get it perfect all of the time, as the chain line will change for each gear.
The best method I have seen are the downhill gearbox bikes, where the pivot and the front sprocket are mounted at virtually the same point like a motorcycle. There will still be normal anti-squat characteristics under acceleration, but the chain line is so close to the pivot line that pedaling torque on the suspension is minimal.
Yes. I was only referring to the system with a pivot concentric with the bottom bracket, thoughgogo said:
To find the "neutral pivot line":
Extend the chain line until it intersects a vertical line through the front hub. This intersection point is the instant center of rotation. A line from this point to the center of the rear axle is the pivot line neutral to pedalling forces.
Lock
100 MW
I wonder if Daymak still have that Made-in-Yongkang "Dolphin" style electric scooter mounted on top of their sign out front. The one with the made-in-China plastic bits rotting in the sunshine? If their showroom is still 95% offroad gas powered machines?
Tks
lOCk
Tks
lOCk
