Woosh Bikes

Andy88

Esteemed Pedelecer
Nov 6, 2016
747
135
69
Ayrshire
Trex when will those new models be available? Im not back in the UK till February

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trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
they are all about the same price. What makes the difference is the motor (£20 for the Big Bear). The Bermuda can be supplied with either 13AH or 15AH (+£60).
Big Bear still suits me better

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Yes, I think so too. The Big Bear has excellent acceleration.
 

Wingreen

Pedelecer
Jul 28, 2015
194
59
Anglesey
Unfortunately, it is a very heavy bike at around 26kgs so it isn't the easiest machine to manoeuvre on to high-mounted cycle carriers, even if the weight is within the permissible limit.

Tom
If you need to transport the Big Bear I can certainly recommend the Exodus towbar carrier. At £60 its a no-brainer - though you would need a towbar. I can also vouch for the Big Bear. It has taken me along some fairly rough routes and come out the other side unscathed.

http://www.halfords.com/cycling/bike-racks/towbar-mounted-bike-racks/exodus-2-bike-towbar-mounted-cycle-carrier
 

Trevormonty

Esteemed Pedelecer
Jul 18, 2016
1,135
564
17
NZ
I


Most hub drives are banfun? Can anyone tell me the crucial components for upgrading to make the bike as comfortable as possible?

Andy

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Gore TeX rain coat and leggings, wellys, thermal underwater, good gloves.

For bike Suntour NCX suspension seatpost, brilliant on rough surfaces and poor roads.

The cheaper derailuer gear sets are not any less reliable than high end stuff for daily commutes. It is quality of shifting is were higher end components shine. An ebike allows you to hold gears longer so less shifting required.

For MTB it is different, suspension is critical air shocks minimum ideally mid to high end. Also good quality gears, as you will be doing a lot shifting even with motor.
 
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trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
the wide range of assist means that you hardly ever need to change gear on the Big Bear. You just select one that suits your cadence then keep it as long as you like. On hills, you can use the throttle to adapt the assist to the gradient and keep to the exact same speed. It'll climb 8%-9% hills at 15mph. A hub gear will reduce maintenance a little bit because you can have enclosed chainguard but would add about £70 to the price.
 
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trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
that's easy to calculate. Maximum current * battery voltage * motor efficiency.

Maximum current: 20A.
Maximum voltage: that depends on the state of charge of your battery. On a freshly charged battery, you have 41.5V, the voltage sag at 20A is about 1.5V, so maximum voltage is 40V for a full battery.
The maximum efficiency is 85%. That will drop significantly at very low RPM or very high RPM.
Assuming you ride on a flat road on a fully charged battery, you would get near maximum efficiency. The mechanical output is thus: 40V * 20A * 0.85 = 680W.

In practice, you get somewhere in the region of 550W to 680W because your battery voltage will drop a bit with the battery temperature and also, the efficiency drops a bit after 15mph.
It's still a lot more than smaller motors.
 
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trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
250W? that what you get when you run the bike in test mode.

250W mechanical + 10% allowance for road friction = 275W mechanical allowed at constant temperature (25 degrees Celsius).
You only have to ride the bike slowly to avoid overheating and never go over 15mph on a flat road.
 

Andy88

Esteemed Pedelecer
Nov 6, 2016
747
135
69
Ayrshire
that's easy to calculate. Maximum current * battery voltage * motor efficiency.

Maximum current: 20A.
Maximum voltage: that depends on the state of charge of your battery. On a freshly charged battery, you have 41.5V, the voltage sag at 20A is about 1.5V, so maximum voltage is 40V for a full battery.
The maximum efficiency is 85%. That will drop significantly at very low RPM or very high RPM.
Assuming you ride on a flat road on a fully charged battery, you would get near maximum efficiency. The mechanical output is thus: 40V * 20A * 0.85 = 680W.

In practice, you get somewhere in the region of 550W to 680W because your battery voltage will drop a bit with the battery temperature and also, the efficiency drops a bit after 15mph.
It's still a lot more than smaller motors.
Ive learnt so much here and now trying to give something back where I can. Thanks everyone

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