Did I buy the right size bike?

[SAN]

Are any of you guys a similar height to me with a 21" frame?

Been there, done that.
I'm 6'2" with an inseam of 35" and bought a 21" MTB frame a few years ago. That after a short test and trip outside the shop. But I never got used to it and didn't feel comfortable with the size and replaced the bike with a 19" after a while. For me that was the correct size.
My hybrid-bike is 21" and have no problem with that frame.

You say you are 5'11", with an inseam of 34.5". I beleive you have very long legs?

 

[sparkysx]

yep very long, if I had my dads torso length I would be 6'3"

 

[sparkysx]

what about the rear hub vs bafang mid drive, which should I go for?

cheers

 

[sparkysx]

with the smaller battery, does that just decrease my range?

 

[sjpt]

The smaller battery might slightly decrease maximum power. It depends exactly why it is smaller, but if it is built with fewer of the same cells it will have fewer in parallel (***) and be able to deliver less current. It depends a lot on the cells, and whether it is the battery that limits power or the controller/motor. I suspect you wouldn't be able to feel much difference, but there are lots of people here who can give a much more precise and reliable answer.

(***) sorry, I stupidly said 'series': spot the deliberate mistake, now corrected. thanks, Nealh

 

[Nealh]

The smaller battery might slightly decrease maximum power. It depends exactly why it is smaller, but if it is built with fewer of the same cells it will have fewer in series and be able to deliver less current. It depends a lot on the cells, and whether it is the battery that limits power or the controller/motor. I suspect you wouldn't be able to feel much difference, but there are lots of people here who can give a much more precise and reliable answer.

A battery always has the same amount of cell groups in series depending on it's voltage, whether higher or lower in capacity. It will be cells in parallel that differ in number to make up capacity measured in ah.

 

[aardvark5]

with the smaller battery, does that just decrease my range?

Nealh will probably correct me but when I started with eBikes I read an article where you multiply the volts by the ah and divide by 20 to give you an 'average' distance.
eg 36v x 10ah = 360 / 20 = 18 miles.

 

[sparkysx]

I rode the scott e sub today and tbh, I was under whelmed, which I'm glad about, because if I had liked it I'd of had to shell out £1299!

 

[aardvark5]

I rode the scott e sub today and tbh, I was under whelmed, which I'm glad about, because if I had liked it I'd of had to shell out £1299!

Most people on here will agree the best way forward is to buy a great bike and convert it.
I originally bought a Cyclotricity Stealth which virtually fell apart but then bought a Trek 4300 second hand for £140 and put the Cyclotricity electrics on that, touch wood it is my main bike and still going after 5 years.
I then bought a second hand Trek Hybrid 7.5FX and put Cyclotricity electrics on that but to be honest I would prefer another MTB as a backup.
After 5 years of eBiking I know exactly what I need to do with my bikes and the Hybrid isn't built for some of the places I ride.

 

[sparkysx]

I am going to be using this on the road so do I need to stick to the 250w?

 

[sjpt]

You need to stick to 250w if you want to be legal on the road ... or to get insurance, tax etc.
The chances of being caught with more than 250w are fairly small, but if you were involved in an accident it could be quite a big issue.

250w is a nominal continuous rating. Many legal motors will give 500w for a short time, I believe some will even give 750w. The max depends on the motor, controller and battery.

 

[aardvark5]

I am going to be using this on the road so do I need to stick to the 250w?

You've had the answer above but my experience of doing 30mph on the throttle was not good.
Some idiot motorists will still see a cyclist up front and go into the 'must get past no matter what' mode which means they can accelerate way over the speed limit just to get past you and then pull over in front of you when they realise how fast they're going.
I found it quite dangerous doing those speeds on a cycle and also had the same problems riding my normal road bike at speed so I don't ride that any more.
I dropped the 1000 watt motor down to 250 watt but several times ran out of battery and it was a very heavy bike to ride with the weight of my 1000 watt motor so I went back to a normal 250w.

 

[sparkysx]

will the bafang 250w 36v do more than the 15.5mph?

 

[sparkysx]

I'm happy to go with 250w

 

[sjpt]

You cannot legally be assisted by the motor to go above 15.5mph (same caveats as for the 250w itself). Most motors have clutches so they won't give any significant drag if you are able to drive yourself over that speed. Some motors (or controllers) are programmable and can be set to give power above 15.5; I don't know about that Bafang. If you look on the conversions thread you will see lots of information about programming details, much of it Bafang prrgramming. (https://www.pedelecs.co.uk/forum/forums/conversion-kits-general-discussion.42/)

 

[sparkysx]

what motor do you have?

 

[aardvark5]

I have a 250 watt motor but mine seems to peak out at around 18mph on the throttle on the flat.

 

[sparkysx]

is it a bafang or something else? whats it like up hills? thanks

 

[aardvark5]

is it a bafang or something else? whats it like up hills? thanks

Both of mine are front motors and I get up hills easily.
I've had a rear motor and had a go on my mates Bafang motor and there isn't a lot of difference in my opinion.

 

[sparkysx]

Any experience of mid motors?