Sub £1000 bike conversion

[Aarongriffin999]

Afternoon all!

Only a few months into this game and so still learning, so please excuse the lack of technical language. I am keen to purchase a road legal kit with the option of 500/1000w for fun off road. At the moment I have three options ahead of me and I need your advice.

Rider details:
Height: 172cm
Weight: 76kg
Age: 30
Commute:
Distance (A to B): 2.9 miles
Return: 5.8 miles
Steepest gradient: 22.2%
Ebike knowledge: not a huge amount!


Option 1: Use my current bike.
The bike I have (photographed in my kitchen) is a GT Transeo 4.0 (pretty much the same as this, the details and specs are here), it has a 27 inch wheel size and disk brakes. The rear dropouts are vertical and 13.5cm apart. It has an 8 cog speed Shimano gear system on the back wheel but I don't think it is a freewheel, but I don't know if this matters. The frame triangle is approx. 38cm from bottom to top, 48cm across and 60cm to link them so I think there will be plenty of space for the battery. My issue is that the frame is aluminium so I am wondering if this is an issue. It is also currently a hybrid so only has a max space of 5.5cm for the rear tyre to fit into before it starts rubbing the frame. I was thinking cyclotricity duel kit?

Option 2: Buy a second hand bike and attach a kit
Anyone done this? I am assuming that there are common bikes used? An email back from cyclotricity said "we do a 48/12 rack and a 48/12 frame and the ds-6 frame type", but I have no idea what that means.

Option 3: Buy an ebike ready made.
I was thinking about the Woosh Karoo, but there are so many available.

What would you do? Any help appreciated!

 

[anotherkiwi]

Welcome!

22% isn't a hill it is a ramp... Anything above 15% you are getting into mid-drive with correct gearing or 500W+ geared rear hub territory.

The kit you mention isn't legal despite what they say. Not being able to switch is part of the law.

Your current bike is fine it will need a hydraulic brake on the front. Woosh has a powerful rear hub kit and a mid drive kit that will do what you want.

 

[Deleted member 4366]

Those 500w/1000w with the big direct drive motor are not really suitable for yourGT bike, so you can cross that one off as an option.

Other options depend on how fast you want to go. My preference would be to convert your bike with a rear geared cassette motor, a 48v down-tube battery and KT controller with LCD display. You can choose the motor according to how fast you want to go. Cost would be about £600. You could do it for about £400 if you're not too bothered about speed.

You could get a ready-made bike. That's a lot simpler, then sell your GT to claw some money back. Obviously, with a ready-made one, you get warranty and backup. Conversion doesn't work out that much cheaper, but it allows you to get a system with exactly the speed and power you want, and is better if you like to be self-sufficient.

 

[Aarongriffin999]

@anotherkiwi thanks! I laughed at the ramp comment, it is a bridge I have to hit every day. I need to be road legal though so I will have to stay at 250w. Will check out Woosh. No experience installing a mid drive, are they as "plug and play" as the other kits?

@d8veh I've seen you are a fan of the KT controller. Sorry to ask you to do this but would you mind adding links to what you said before so I can take a look at precisely what you mean? I need to be road legal so I'll need to stick to the 15.5mph.

 

[Deleted member 4366]

For any kit with an LCD, you can set the speed to 15.5 mph or anything else.
Kit here:
https://www.ebay.co.uk/itm/36V350W-28-700c-Rear-Motor-with-Cassette-E-bike-Hub-Motor-Conversion-kit/222254740610?hash=item33bf6a3482:g:~VgAAOSwE8daXvAc

battery:
https://www.ebay.co.uk/itm/36V17Ah-Electric-bicycle-Li-ion-Battery-with-Cellphone-charging-USB-3A-Charger/222314423780?hash=item33c2f8e5e4:g:FJAAAOSwfkdZkt3z

Mid-drive kits are easy to install. They're a bit more expensive and, by most accounts, not as reliable as hub-motors, and harder to fix when they go wrong. At only 75kg, you don't need a crank motor for that hill unless you have some medical condition that stops you from pedalling. Maybe that would be different for a 22% Alp, but not a bridge!

 

[DynatechFan]

just my 2 peneth, After borrowing a £2k crank drive Merida for a month I converted an old 26" wheel MTB with a YSBattery geared rear hub kit off ebay - mostly for road/commuter use. Very happy with it even on steep hills, better to ride than the Merida in many ways. The hub came with a 350W sticker on it that I removed - it looks and behaves pretty much like a road legal kit - just wondering why you *need* your kit to be 100% road legal

 

[Woosh]

for steep gradient, you'd need something like the 48V SWX02 hub kit. This motor has winding code 16, that makes it quite good at climbing hills.
The kit comes complete with everything you need, 48V 11.6AH battery, charger, choice of pedal sensor (left, right, Hollowtech, triple chainring), thumb throttle and sensored brake levers.
We also stock DNP 8-speed freewheels for them.

http://wooshbikes.co.uk/?hubkits#swx02-48v-kit

 

[spanos]

Nothing climbed hills like my 350w BPM hub running at 48v

No longer have it, or indeed any hub bikes, I miss it for speed up hills

Legal cranks cope perfectly but not at same pace

 

[Aarongriffin999]

Thanks so much for the links guys, very tempted by both @Woosh option and @d8veh option. Dumb question but I'm assuming they can take disk brakes?

To answer @DynatechFan I guess if something were to happen (like going into the back if a car, or a kid running into the road and getting hit) then having a road legal bike means not being pulled up on it if insurance claims happen. But I guess for day to day the police round me don't care, but I guess that isn't a the point.

@Woosh just to say you website footer is taking up most the mobile page using chrome on android.

 

[Woosh]

Dumb question but I'm assuming they can take disk brakes?

yes. I have 180mm rotor on mine but it will take 160mm rotor too.

 

[Deleted member 4366]

The Woosh kit is stamped 250w. All you need to do is set the speed limit to 25km/h and you're legal.

 

[Aarongriffin999]

The Woosh kit is stamped 250w. All you need to do is set the speed limit to 25km/h and you're legal.

My understanding was that the hub had to show what wattage it is alongside being speed limited. Would it be road legal to have a 350w limited by the LCD screen to 25km/h? I just reread the stuff on this website and it says it isn't clear.

 

[Woosh]

Would it be road legal to have a 350w limited by the LCD screen to 25km/h?

you need to affix a 250W label.

 

[Aarongriffin999]

Thanks Woosh, looking forward to buying the kit you suggested then, thanks so much for the help. I'll need to work out a solution with the brakes as mine have both gears and brakes in one unit on the handlebars. Brilliant, thanks for the help guys.

 

[Woosh]

I'll need to work out a solution with the brakes as mine have both gears and brakes in one unit on the handlebars

you'll need to fit a pair of these:

 

[Woosh]

I forgot top mention that we usually stock them but if we are out of them, you can buy them here:

http://wing-ebikes.co.uk/?page_id=3002

 

[wheeliepete]

You can retain your existing levers by using the hydraulic brake sensors. I think Woosh stock them. You may need to lengthen the wire and/or change the connectors as I'm not sure they are the same.


Edit; I must learn to type faster!!

 

[Aarongriffin999]

you need to affix a 250W label.

Sorry, last question, because if the word affix. If I had a 1000w motor limited to 250w using an LCD and then put a 250w stamp on it it would be road legal? I'm asking because if that is the case then I'll aim for a higher wattage to blast the bike on private land without having to change anything except the LCD.

 

[wheeliepete]

The power output from the motor comes from the controller and the battery. If you fit a motor capable of taking more power you will need a controller and battery able to provide it. The 350w/48v bafang will suit your needs. if you want more power, build another bike.

 

[Deleted member 4366]

Sorry, last question, because if the word affix. If I had a 1000w motor limited to 250w using an LCD and then put a 250w stamp on it it would be road legal? I'm asking because if that is the case then I'll aim for a higher wattage to blast the bike on private land without having to change anything except the LCD.

If you're thinking of one of those big direct drive motor 1000w kits, you need to run them at 30 amps or more to get any sort of reasonable performance out of them. That means that you need a big heavy expensive battery. One of the cheap 48v 11.6 Ah ones will give you a range of about 10 miles and will need replacing in less than a year.