Cyclamatic: The Beastamatic is dead! Long live the Beastamatic

[Deleted member 4366]

@d8veh: re cell capacity issues; do you think replacement of the whole existing cell set with say a 3s3p x 3 of 3600mAh 18650's might be a goer? If the cheap Chinese ones turn out ok, it would only cost about £55 + charger by the look of it...

Bike arrived today and have it assembled, but one crank nut is missing! Frustration!

I can't say about these cells until I test some. On past history, they don't live up to their claims, so I wouldn't risk it yet. Better to go down the lipo route as you know about electrical stuff. A 5.4aH pack would cost about £50 plus leads and connectors, or 10.4aH for £100. You still need a wattmeter, charger and power supply for about £30 total. Say £150 all up. This pack might be more useful if you do a later upgrade because it'll give as much current as you want, while as you're more or less over the limit for the present battery and those cells.
http://www.ebay.co.uk/itm/5200mAh-18-5v-20C-LiPo-5-Cell-18-5-RC-Wif-Akku-Battery-/160430615548?pt=Radio_Control_Parts_Accessories&hash=item255a68ebfc

 

[evendine]

@d8veh: Thanks for the link to those LiPo packs - look good for the money and you've obviously tested them thoroughly already. Do you know if 4 would fit into the existing case?

re: cheap Chinese batts - I contacted the major supplier of tagged 18650's on ebay and they tell me the 3600mAh cells that look the best bet are 10C

eBay - The UK's Online Marketplace

Given that they're so cheap (£1.88 each) , I'm tempted to buy 10, build a 3s3p 10.6Ah 11.1v set and give the 'booster pack' approach a try. A 36v charger will be a useful investment even if it doesn't work out. Do you see any possibility of damaging the existing components if the pack goes out of balance during use? I could add a low voltage monitor to the build as you suggested...

 

[Deleted member 4366]

I always say, "Give it a try and then you'll know if it works". The worst that'll happen is that you'll lose a bit of money and you can always use the cells for your lights if it doesn't work. I'm pretty sure that the best way to charge them would be separately from the main pack, and just use them as a booster pack. Then you have the option of adding in an extra cell for 40.7v and a bit more speed. Plus, you'll be able to see how they go down compared with the main battery, which will give an idea of whether a permanent installation inside the case is possible. You can charge them with a lipo charger like this:
IMax B6 Lipo NiMh battery Balance Digital LCD Charger | eBay
Then you need a 12v power supply for it, which can be a car battery of one of these:
12V 5A Power Supply Rc Lipo iMAX B6 Balance Charger 937 | eBay
Then you need some bullet or Deans connectors and a balance lead like this:
211F 2x7Pin Balance Cables for 6S LiPo Battery Charging | eBay

The 18.5v lipo packs that I showed before fit in the case nicely. I used two for 5.2aH 37v and couldn't get another pair in because I mounted my bigger controller in the bottom. You might just get 10.4aH, but it'll be tight. you could always leave the top off the case if they stick out a bit - handy for charging.

Whatever system you use, you must monitor the voltage of the batteries while in use, so you might want to get one of these:
eBay - The UK's Online Marketplace

 

[evendine]

Charged the standard batts fully and took it for a test ride, but I'm getting two lights on the handlebar indicators when the motor is under full load; which I assume indicates voltage sag... Is this normal (don't remember it happening when I tried another bike a few months ago)?

 

[Scottyf]

Yes this would indicatate the current draw is creating the voltage sag.

My current Lipo setup drops 1v across 12cells at a 1.3c draw.
So roughly 0.08v per cell.

My 18650 cells would drop alot more maybe around the 2v mark on a 10s setup. This was using panasonic cells at a 2c rate. So 0.2v per cell.

But they are all rated differently. You need to do some testing on it.
Generally Ebikes are quite low draw applications in standard trim.

 

[evendine]

Understood, but what I'm wondering is should I expect a voltage sag under load sufficient to cause the green light to go out using a brand new fully charged standard 24v pack? Maybe I've go a sub-standard pack?

re: 18650's - really interested in your configuration Skottyf - where did you get the cells? Did you make a booster pack (i.e. add them to your existing pack) or did you build a new pack altogether?

 

[Fordulike]

Understood, but what I'm wondering is should I expect a voltage sag under load sufficient to cause the green light to go out using a brand new fully charged standard 24v pack? Maybe I've go a sub-standard pack?

re: 18650's - really interested in your configuration Skottyf - where did you get the cells? Did you make a booster pack (i.e. add them to your existing pack) or did you build a new pack altogether?

Yes, the green light going out under load is quite normal.
As long as under load the yellow and red are both still lit, then the battery is probably ok.
Straight to red under load on a fresh battery might indicate a faulty battery.
The best way to test is to fully charge the battery.
Then on a fairly flat route, power the bike with throttle only till it shows a red light only whilst stationary. Stop every now and then to test.
Then head home using pedelec. Should have enough power left to make it home, if you have chosen a short route.
You should get at least 15 miles out of the battery on throttle alone, with a sound battery.

 

[Scottyf]

re: 18650's - really interested in your configuration Skottyf - where did you get the cells? Did you make a booster pack (i.e. add them to your existing pack) or did you build a new pack altogether?

This was with my old 36v 9amphr battery made up of 10 cells in series of 2250mah, 4 blocks in parallel. This was a 40cell battery. Pretty standard for an ebike.

I never made a booster pack as I got bored of it and went straight to Lipo. I sold that battery. It was only 6 months only at the time.

You can make a booster pack so long as its in series with an original battery and is of equal amp hours.

My lipo setup now is very similar to D8veh's (and many ebike users on the internet using RC lipo).

I simply moved onto RC lipo becasue there are alot of connections, chargers and advice on the net about it rather than making a heavier 18650 celled battery. This also offer higher discharge rates.

Only down side is life cycles and they are more hazadous if you dont treat them with care.
There also about as light as you can get for the moment.

 

[Deleted member 4366]

It sometimes takes a couple of cycles for the battery to get full capacity, plus it's not very warm at the moment. both of these factors will cause lower efficiency from the battery. Also, you can't take too much notice of these indicator lights because they're not an accurate representation of battery voltage.

 

[evendine]

Just bought a 2nd hand Cyclamatic on ebay for £100 which apparently has a good battery (tested on another bike) and was working until a couple of weeks ago, but now has no lights on h/bars. Any thoughts on what might be wrong appreciated (sounds like a wiring problem)?

In any case, I can now experiment with battery pack upgrades without losing warranty on my new pack - looking at 2 x 18.5v 5200mAh Lipo's that everyone seems to rate as a starting-point. Anyone know a reasonably priced UK supplier?

 

[Fordulike]

Just bought a 2nd hand Cyclamatic on ebay for £100 which apparently has a good battery (tested on another bike) and was working until a couple of weeks ago, but now has no lights on h/bars. Any thoughts on what might be wrong appreciated (sounds like a wiring problem)?

In any case, I can now experiment with battery pack upgrades without losing warranty on my new pack - looking at 2 x 18.5v 5200mAh Lipo's that everyone seems to rate as a starting-point. Anyone know a reasonably priced UK supplier?

I had my eye on that baby too, but too far to travel to collect.

If you can't get it to work, then I'll take the rear wheel off yer hands for some lolly

 

[Deleted member 4366]

The prongs on the base plate fit into clips on the battery. It's possible a clip has been bent apart so that the battery doesn't make contact. Remove the battery and check the voltage on the clips. Install the battery and take a side off the little compartment under the it. Check that you have battery voltage on the power wires going into the controller, and while you're there. check the other connectors. By then you should've found or repaired the problem if the seller was telling the truth. £100 for a CYCLAMATIC, the best bike in the world: Bargain!

 

[Deleted member 4366]

I had my eye on that baby too, but too far to travel to collect.

If you can't get it to work, then I'll take the rear wheel off yer hands for some lolly

And I may take the rest of it, if you're not too far away.

 

[evendine]

I'll be more than happy if I can get it to run - thanks for the advice...

It's a bit rough round the edges but with a matt black respray should make a good test rat!

 

[Fordulike]

d8veh, I'm still using my bike at the mo, so not keen to strip the hub down again.

By chance, do you know how the nylon spur gears are attached to the assembly.
Are they held on by a circlip? Too much grease on them to notice the other day.

I am warming to idea of either getting a nylon or metal replacement fabricated, or a repair job.

Be a shame to see the Beastamatic's demise because of a blooming plastic cog.

Why oh why is the axle such an odd length

 

[evendine]

If I end up breaking the 'Rat' you guys are first on the list for any spares, of course!

@Fordulike: There are some good low cost '3D printer' services around these days - they can make virtually any shape in many different types of plastic (and even metal). Have been thinking of getting an extension to the body of the batt case fabricated, so that the uprated controller + 2s2p Lipos will fit...

Here's an example someone did with a home build 3D printer:
http://makerblog.anat.org.au/2011/12/from-conception-to-reality-how-to-3d-print/

...and another with better finish:
http://www.instructables.com/id/3D-Printed-Clock-and-Gears/

 

[Deleted member 4366]

We have a good 3D printer at work. It prints ABS. I'm not sure that it's strong enough for motor gears.
Fordulike, I haven't taken my motor apart yet, but I assumed the gears had pressed-in bearings that just sat on the pins. I was wondering whether the frame could be narrowed a bit with a good downward stroke from a foot when it's laid on its side. That's why I'm interested to get another frame p to try it. Then any motor could be used. Aluminium will permanently deform given enough welly, but you have to do it in one move because it work-hardens

 

[Fordulike]

We have a good 3D printer at work. It prints ABS. I'm not sure that it's strong enough for motor gears.
Fordulike, I haven't taken my motor apart yet, but I assumed the gears had pressed-in bearings that just sat on the pins. I was wondering whether the frame could be narrowed a bit with a good downward stroke from a foot when it's laid on its side. That's why I'm interested to get another frame p to try it. Then any motor could be used. Aluminium will permanently deform given enough welly, but you have to do it in one move because it work-hardens

I may be willing to give that a go, but was just under the impression that aluminium snapped really easily when forced beyond its formed shape.

 

[evendine]

'...We have a good 3D printer at work. It prints ABS. I'm not sure that it's strong enough for motor gears....'

This outfit does laser-cut stainless - might do the job if the sheet they use is thick enough:

Ponoko - Ponoko - United States - Ponoko

(They do a wide range of plastics too)

This is interesting too:
http://www.fabathome.org/wiki/index.php/Main_Page

Looks like they've build a chain-ring for a bike which works...

Has anyone contacted SportHQ re original spares?

 

[Fordulike]

Has anyone contacted SportHQ re original spares?

Did that a few days ago. Just waiting for a reply