Globe (Specialized) commuter build thread

After catching up with Full-throttle recently he has convinced me I should be capturing more info in build threads. So here goes.

Apologies as some of this info will be back-posted. I'm 80% the way thru the build and have learnt a lot.

I spent a bit of time at the LBS and had been eyeing off this bike. An aluminium framed single speed with steel front forks. After hacking my brushed BB drive Aprilias it felt like time to build a bolt-on front hub bike. So $600 later I had the base bike.

Here's the before pic.


I really enjoyed the handiness of the front basket for quick shopping trips into town.
But riding it to work without a moto at 15kph it wasn't a viable longterm prospect. I'm frequently late out the door, and my knees aren't improving with age. Time to find a front motor.

I wanted a hub with a nice aluminium finish to match the minimal look of the bike. I did consider a MPII or mini-pie, but they just would have looked wrong. A black mac would have done. I came a across a local Ezee motor in a 700c quality rim and knew these motors were good quality, so rather than undercook the starting torque with a non-name mini hub I went for the ezee.
Six 5s 5Ahr bricks were purchased for batteries (to be run at 10s) and I had a generic 17amp KU60 controller in the shed, as well as a thumb throttle.

The front rack made a great commissioning platform for holding the various bits and ghetto runs down the street.
View attachment 1

An old cassette case (remember them!) came in handy for an outer case. An ebay 3v to 30v voltmeter made a simple check on voltage sag during test runs as there is no BMS with RC lipo. I made some 3:1 parallel harnesses with 4mm banana plugs to get the 6 lipo bricks into a 10s 15Ah state.

Here she is in Full beta mode after a test run down to the local watering hole.

I was surprised at that point of how nice it was to ride despite the weight up front. I had discounted how nice it was to be able to swing the light aluminium rear end around - perfect for keeping in the hallway of our house and shooting downtown for a late night snack or errand to the ATM machine.

The aluminium frame did ring like a bell a bit on takeoff but once the gears settled in on the virgin hub it got a lot quieter. I found later on that controllers made a difference to startup also (more posting on this later).

The ezee had a mountain of torque at 17 amps. Probably too much as it would lift quickly to 37kph. On 28C tyres traction was an issue. The steel forks showed no sign of wear but who knows in the long run. And the front forks would be flexed forward with each hard start - probably ok in the long run but you never know!

I fancied the idea of a dual suspension dual drive after seeing D8VEH's setup so I went looking for a cheap minihub so I could retire the Ezee.
I did find a new bag that suited a bit better for looks and took her out on last weekend's group ride in Melbourne. Got lots of looks and compliments for the minimal build.



I also started to think about how to get the RC lipo bricks into the bottom of the frame for handling improvement. But after riding it awhile I decided it wasn't needed. Although it'd be good to have the full basket back so I could fit more beer in.

Google sketchup was handy for planning this in the most compact shape. I tried to work on a wooden vintage look triangle bag in leather or a wooden triangle with a vintage look.

An ebay 3v to 30v voltmeter made a simple check on voltage sag during test runs as there is no BMS with RC lipo.

Click to expand...

http://www.methtek.com/2011/11/12/lvchvcparallel-boards-10/

You probably know this already but I'll throw it out there anyways. I see no problem with a voltmeter as you know what #'s to look for when it's time to let up on the "juice". I think a LVC/HVC board similar to what's linked above would give you less to worry about. Plus, you could lend it out to friends knowing there is an active safety measure. Otherwise, clean build! 8) I have my batteries on the front too. At the moment, it's not the most secure rig as I've got it in an old lumbar pack made of ballistic nylon (cordura) and "ghetto" strapped it down. Doesn't really affect the ride much as the rack isn't connected to the wheel just like yours. I believe they are called "truck" or "trucker" styled bikes. Designed to be used by businesses to get their stuff moved via bicycle.

Hey that's true about the voltmeter. But the voltmeter was just a plugin for commissioning so i could read the 15mm high numbers at night

I ended up with a Hobbyking 30 dollar wattmeter but reading one of those during commissioning at speed is suicide. Now I know that sag isn't an issue it was a viable solution.

More posts a bit later this afternoon...

I started thinking more about getting the batteries out of the basket for beer-space and getting somewhere to hide the controller and wiring. Underneath the basket was looking good for the controller.

While looking around for a mini motor I noticed that it didnt cost a lot more on freight to get a bottle battery. So I order a q100 kit with bottle battery (more like a thermos) as it could be used on a wife bike anyway.

A quick poke around the internet gave me some inspiration. I like the current trend of black+tan bikes, but the black and polished aluminium is cool too IMHO.

I thought about replacing the front basket with a vintage wood crate. or maybe hiding each liPo brick inside a steel beercan (Sapporo or similar). I'd still like to do that one day. A six pack of Zippy LiPo please! 8)

Before the batteries could be settled my q100 arrived. It was noticeably smaller than the Ezee - which was really overkill on torque. These are 700c rims, don't underestimate the size of the Ezee. A BPM or MAC would be about in the middle for size from memory. Might be wrong

View attachment 1
Of particular notice was the poorer quality of the chinese rim on the q100 out of china. The join around the braking face was maybe 1mm misaligned. Should wear some brakes out fast. But not unsafe at the low speeds of this bike.

I also received a 6FET, 9FET and 12FET with my q100 hub and bottle battery. Which was just as well. I soldered the shunt on my generic controller but after a few minutes at higher power my KU60 went up in smoke.

The 9 FET drove the q100 at 700 watts (readable on my turnigy wattmeter now inline). It went pretty well for such a small motor. But still quite growly on takeoff as the Ezee was.

I switched to the 12 FET and it pulled 1001 watts from the battery at WOT. Too much for the little internal gears in the long run I suspect, and not in keeping with what the bike is about.

So I switched back to the tiny little 6 FET. Remarkably the little 250W controller gave a nicer startup and was pulling 14 battery amps from the RC lipos.
I think it might have a faster frequency, if I am right that might be why the growling was less noticeable down low. Very quiet and tiny outfit pulling 600 watts from the battery. A good fit. Bigger isnt always better.
Checked the motor, controller and connection with a 30 dollar laser temp. No bad joins. Motor and controller barely warm on a 16 degree spring evening.

In the last few days I have been ducking down to the shops quite a bit and the q100 is taking everything I throw at it. Not the fork bending torque of the ezee but still moderately peppy at the lights.

I have become a bit paranoid about someone mucking around with the RC lipos while parked and finding a corpse next to the bike. And I would rather the lipos to go with the ezee on a dual drive as I mentioned earlier.

So I have started to think about using the bottle battery. The site says it is limited to 10 amps continuous though, and 25 amps burst. It'll be interesting to hook it up and see if the controller they sent it with can still pull 14 amps or if the battery BMS pulls it back to 10 amps.

Here it is sitting loose in the frame. The plug and go charger and the inbuilt LED gauge seems nice and simple. No chance of over discharging. No need to remove the RC lipo and turn the 10s pack back into 5s twins and parallel charge. Pub bikes should be simple and secure.


The smaller controller is easily stashed under the basket. I will probably fit a small plywood base in the basket just to hide the wiring. Less chance of being caught in the rain and water getting on a connector too. You never know...

This post brings me up to current. I might switch the rear gear to a 17 or 16 tooth (its 18 stock). I should still be able to add a little leg power then at full throttle on the flat into headwinds.

Excellent, looks super clean and has style.

You should
[youtube]InRDF_0lfHk[/youtube]

Or matte black contact paper from the supermarket

Where have you positioned the controller located?
I've got a similar battery in for testing, but it's 9Ah and about 1/3 smaller, what Ah rating is yours?
They do make a 12A controller that fits into the base of the unit which is interesting.

So I have started to think about using the bottle battery. The site says it is limited to 10 amps continuous though, and 25 amps burst. It'll be interesting to hook it up and see if the controller they sent it with can still pull 14 amps or if the battery BMS pulls it back to 10 amps.

Click to expand...

They newest gen of euro spec batteries have max current rating with a time rating, ex 5 mins max at 20A.
Non mention of the BMS cells power after prolonged high load in any of the documentation i've read, usually up to the manufacture/seller to accordingly spec a controller.

But I could be wrong as some of the pedelec based batteries are well engineered.

Hey man,
the tiny ku60 is up under the front beer-basket. It came stock at about 14.5 battery amps I think (info is above somewhere from memory) so the bottle battery must be at least 15 amps. Maybe 20. It's quoted as a 9Ahr battery. I am amazed at the range I can get, but on those skinny 28 tyres with flak sides I run about 70psi, and if you cut the throttle it just rolls and rolls and rolls. And rolls.

Must have a go at shunting the controller, and see if I can get 17amps. Using the laser temp logger, it doesn't get above about 32 degrees currently.

I wish there was a 15s equivalent battery in that package. That'd rock as an off the shelf set and forget solution.

I need to change my rear single sprocket. It cruises at about the 30kph mark but legs top out at about 22kph on the stock ratio.

Visited SamD's mans cave today. Got treated with freshly ground coffee and had a ride on the Globe commuter and a cargo bike.

The Globe goes really well, much better than the Q100 I have. Slow wind makes big difference.

Glad you liked the slow wind F-T. It was good to see you in 'smell-a-rat', hope we can hold a ride over here one day.

Might just get this bike out for the Melburn Roobaix.

Great build! I'm looking to do something similar to what you have. Where did you get the battery, controller and motor?