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Alien 350w kit- Wheel size change, Battery replacement/upgrade

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Hi all,

 

Finally decided to go for a second hand alien conversion off ebay. First impressions are very positive, the conversion is about 18 months old ( battery 10 months due to faulty original).

 

Took it out for the first commute yesterday, 10.5 miles each way mainly flat but very exposed to wind ( especially the Severn Bridge!). I kept it in High pedelec mode for about 85% of the time and managed an average speed of nearly 18.5mph which is pretty good. I have no opportunity to charge my battery at work ( unless I buy a voltage converter and charge it in my truck though I'm not sure if that is good for the battery?).

 

I am thinking of putting the kit on my Specialized Crosstrail hybrid because the Carrera frame it's on at the moment is a bit small and I prefer the 700c size wheels so this leads to my questions!

 

1) Can anyone recommend a bike shop ( preferably near Newport/Bristol) who can supply and fit my hub into the right strength rim and spokes?

 

2) Any idea how much that would cost?

 

3) I will seriously be considering a battery upgrade in the near future, what power rating do you suggest, where can I get one and will it fit straight into the rack.

 

4) Can I upgrade to 48v? What needs changing if I can.

 

Thanks for your help

 

Andy

  • Author
If you're going to change the motor to a different wheel and get a new battery, you might as well sell what you've got and start afresh. Ebike Nirvana - about 25mph in 700c wheel. 50 to 70miles if you like to pedal:

Bafang CST 36V 500W REAR Driving E-Bike Conversion Kit. - BMSBATTERY

36V 20Ah Li-Ion Shrink Tube EBike Battery Pack - BMSBATTERY

 

Cheers for the info d8veh

 

I'm keeping what I got, just thinking of swopping the gear onto my bigger bike. The battery is fine at the mo, just thinking ahead mainly because as it's capacity reduces I may run into problems because my commute is probably fairly near it's limit. Would I be right in thinking the battery you have provided a link to from BMS will not slot into my carrier or be a direct link into my controller? Are there no dealers within the UK for these batteries?

Any info from fellow ebikers regarding where I can get my hub fitted into a 700c rim would be gratefully received.

There's a guy on here username catsnapper who does wheel building I think. Going up to 48v you'd need a different bms and controller as a minimum I think. Your motor would handle 48v okay just depends how many amps you try and stick through it. If it gets hot ease off a bit!

Edited by oigoi

Cheers for the info d8veh

 

I'm keeping what I got, just thinking of swopping the gear onto my bigger bike. The battery is fine at the mo, just thinking ahead mainly because as it's capacity reduces I may run into problems because my commute is probably fairly near it's limit. Would I be right in thinking the battery you have provided a link to from BMS will not slot into my carrier or be a direct link into my controller? Are there no dealers within the UK for these batteries?

Any info from fellow ebikers regarding where I can get my hub fitted into a 700c rim would be gratefully received.

The battery I linked to don't fit into your rack. You'd have to chuck that. It's hideous anyway.

 

Another thing you want to look at is the free-wheel. I don't know which one you already have, but they're normally 14 teeth top gear, which is much too low for a faster motor like the BPM. You need a 11T top gear set, which Cyclezee usually stock for about £25. Alternatively, you can swap your front chain-wheel for a 52T/39T one off a road bike.

 

The 350w BPM can give a lot more than what the Alien kit lets it. The kit's battery and controller both are a bit on the low side. A 25 amp controller would be much better, but then you need a bigger battery to give that current. You could go up to a 48v battery for more speed too, but then you'd need a new controller too because the Alien one is a bit on the small side and would probably over-heat.

 

There's nothing wrong with the Alien kit. It gives more power and speed than most 250w kits, but if you want more speed and/or power than that, you have to change the battery, controller and free-wheel, which is why I'd suggest a different kit.

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