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robocog
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PostPosted: 21:01 - 18 Jul 2010    Post subject: heated grip pads Reply with quote

Bit premature I know, but fancy building a controller at some point for a set in readyness for winter (and the speed I usually take with this sort of project it may not be complete in time for this winter...LOL)

eBay seems to have "very basic" grip heater pads
(eg https://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=270603472601) which are cheap enough for me to want to play with a set

none of the sellers of the cheaper end pads however have any clue as to what sort of current draw they will require

anyone got a set of this style fitted (or even better got exactly this model?)

Are they actually capable of getting hot enough to warrant any form of control in the first place?
(or is it a case of these cheap ones are a bit pants heat wise and only low power?...hence only really requiring on or off)

I guess if I knew what size fuse they required or what the current draw was it would give me a better idea? (maybe?)

Seen a particular make (Symtec?) mentioned on here as being good heat wise (36 watts claimed power), but they seem to be a LOT more expensive

Looking at the pictures the Symtec's 'pads' have lots of thin gauge wiring elements and the cheaper end ones have fewer thicker wires in the 'pads'

Am I wasting my time looking at the cheapo ones?

Regards
Rob
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supZ
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PostPosted: 09:18 - 19 Jul 2010    Post subject: Reply with quote

they look like the symtec ones i put on my 600. VERY good.

obviously not as versatle as the oxfords but not as bulky either (as you use standard grips) and they actually worked unlike the oxfords!!

the symtec ones are £30 odd and have a high and low setting. fit with a good amount of electrical tape and jobs a goodun.

dunno if these cheapy ones will be enough but if they're comparable to the symtec ones then they got me through last winter with toasty hands Smile
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herulach
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PostPosted: 17:10 - 19 Jul 2010    Post subject: Reply with quote

For 3.50 I reckon it's worth a punt. The symtec ones don't have a proper controller, just a high/low/off switch. I don't reckon wiring one of those up would be too hard, just needs a suitable divider circuit to knock the voltage down, although all that will do is keep your hands cooler rather than save your battery.
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robocog
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PostPosted: 20:04 - 19 Jul 2010    Post subject: Reply with quote

Was thinking along the lines of using pulse width modulation (turning them on and off rapidly and varying the ammount of time they are on for) to control it, rather than dumping it elsewhere

More for the sake of doing it/an experiment more than anything TBH

Just unsure if those cheapies will actually get hot enough to justify it
(eg if they get mildly warm at best, no point in building a device to turn them down..LOL)

Will order a set anyway at that price

Regards
Rob
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robocog
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PostPosted: 19:51 - 26 Jul 2010    Post subject: Reply with quote

Just touching the thread as the heater pads arrived today

Put them on a regulated 14.4v supply and they are drawing 1.4A according to my multimeter
they get "quite hot" (BUT not too hot / painful to touch though)

Maybe I won't need any sort of control other than on and off...esp when buried and insulated under a set of rubber grips

will fit them as they are with the simpls switch at some point and report back

Regards
Rob
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robocog
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PostPosted: 20:01 - 24 Aug 2010    Post subject: Reply with quote

Fitted them up after testing them on the workbench and they kept blowing the fuse..
turns out (after taking them off without destroying the evidence) that the left hand grip had a short and had burned a hole through the plastic from where it wrapped round itself and had sat on top of the solder joint...which was pretty sharp

I re soldered the joint so it was smooth and cut a couple of the elements off (so it no longer wraps round itself) and put extra layers of self amalgamating tape round the bare bar for good measure

They both now work...but alas the bikes panels are STILL away being sprayed so don't know how effective they really are when moving along
The grips get "fairly warm" through the rubber...not too hot to touch
Unsure if they will actually be noticable through gloves as well..

Have wired them with a double pole double throw switch which changes them between being wired in parallel and series (so acts like a 'hi' and 'lo' heat setting ....if needed)

I ordered a PWM motor controller that looks like it should be able to fine control the heater elements if the hi and lo switch thing is a bit poop
The unit arrived today, its currently hooked up to a fan on the desk and seems to be doing what I expected it to do and see no reason it shouldn't work for the heated grips just as well

Panels have been away for nearly 3 weeks now, the wait is killing me Sad

Will whore some pics when they come back

Regards
Rob
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herulach
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PostPosted: 19:13 - 07 Sep 2010    Post subject: Reply with quote

Noob question, but about to pull the trigger on these, do they need the grips to be replaced or will they fit under the old ones?
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robocog
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PostPosted: 19:57 - 07 Sep 2010    Post subject: Reply with quote

Mine fit nicely under the original grips no problem
The heater elements are wafer thin
They add very little to the bulk and dont feel any fatter and the grips went back on without any hitch with the aid of some WD40
(they very quickly went from being able to be spun and moved to rock solid as if they had been glued on...so you need to work fast)

I did put a couple of layers of self amalgamating tape on the left hand bar to help insulate it as I heard that the grips can be a little slow to heat up on that side if they are trying to heat the bar as well Wink
It also helps stop any shorting out - which is something the cheap grips I have were happy to do, so an extra couple of layers of amalgam were used directly under the connectors)

I did search high and low for Mrs Cog's hairspray but I don't recall the last time I actually saw her using any (used to be the gold can...Elnet? and was just the best substance in the world for doing grips when I used to mountainbike)

removing the grips /should/ be simple...assuming they have not been glued on
Bar ends/weights off so you can get to the edge of the rubber
Poke small screwdriver under grip and slightly stretch rubber
Spray WD under grip and work it deeper with the screwdriver or the little straw that comes with the WD
Eventually it will just be so loose it will just slip off

Replacing it is as simple as coating the bar with hairspray or WD in my case and squirting some into the grip and getting it on as fast as poss Wink

Have tested the cheapo grips on the bike and I can feel the heat through the grips and my thin ish gloves on the high setting

Got sweaty palms after a few mins of riding so put them onto the low setting and didn't really notice much heat (but then it has been pretty warm recently so not had chance to test them when the air is cold...yet)

The ones I got came with a pretty crappy switch with just on and off
...it got replaced as it looked like it would not survive a mildly damp day let alone a winter

bought a nice small plastic case

Double pole double throw switch (DPDT) wired so it flicks between high off and low settings
Easily done by basically wiring from being both grips in parallel for "high"
Off (where both grips are just disconnected from the supply)
and the low setting is the grips wired in series across the supply

Sounds more complex than it should and will do a simple paint diagram if you need help

I also got the following:
Waterproof rubber cover for the switch
couple of meters of black and red cable
Green 12v LED
bag of "Tamiya radio control" type battery connectors

I think it looks OK (much better than an exposed switch on a crappy steel bracket anyway)

End result is on the left hand handlebar...

https://www.robocog.dyndns.org/motorbikes/gpz/DSCF3300%20(Small).JPG


Regards
Rob
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robocog
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PostPosted: 21:35 - 07 Sep 2010    Post subject: Reply with quote

Series parallel paint pic
Hopefully it will help someone Smile

It is slightly simplified as I actually wired it via a spare wire that is controlled by the ignition to save me flattening the battery if I forget to turn it off!

Regards
Rob
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herulach
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PostPosted: 22:18 - 07 Sep 2010    Post subject: Reply with quote

The plan is to wire it them to a relay that switches off the rear light, and stick the switch somewhere out of the way.

I do like the on/off light idea though.
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spetom
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PostPosted: 07:18 - 12 Nov 2010    Post subject: Reply with quote

I know they're not practical for race bikes. But I'm seriously considering bar muffs over heated grips, despite them looking a little naff.
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Damon
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PostPosted: 10:35 - 12 Nov 2010    Post subject: Reply with quote

Just ordered a set. For that price its worth a play

Cheers
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tahrey
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PostPosted: 17:55 - 24 Dec 2010    Post subject: Reply with quote

robocog wrote:
Series parallel paint pic
Hopefully it will help someone Smile


Sorry Robo, that one's red-X'ing, at least for me. You couldn't put a copy up on Imageshack or somewhere like that could you please?

I don't actually need it but I'm interested to see how you do such a thing with a DPDT, can't quite get it right in my head Smile
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robocog
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PostPosted: 19:31 - 24 Dec 2010    Post subject: Reply with quote

I can see it this end??
Ok copied and hosted on my box...

https://www.robocog.dyndns.org/motorbikes/bcf/series_parallel_wiring_for_hi_and_low.png

In case that doesn't work the direct link for it should be
https://www.robocog.dyndns.org/motorbikes/bcf/series_parallel_wiring_for_hi_and_low.png

Regards
Rob
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tahrey
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PostPosted: 21:12 - 27 Dec 2010    Post subject: Reply with quote

Cool... I'm guessing the ultimate path of current when you flip the switch one way or t'other is as below? With any indicator LED sitting on (and parallel to) either the positive or negative leg coming out the bottom of the switch.

(I had to go work it out diagrammatically in paint to properly figure out what you were showing us... i'm at another one of my low mental ebbs Smile so the battery may be the wrong way up etc)

With, of course, no complete path from positive to negative on the battery or frame when the switch is in the centre position. Overall, very clever!
(I'm sure it's one of those real basic circuits you get shown on week three of an electronics course, but it's been so long since I did anything like that, I've no chance of remembering)
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robocog
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PostPosted: 22:56 - 27 Dec 2010    Post subject: Reply with quote

Yup 100%!

I did buy a variable motor controller from CPC that uses PWM (basically turns them on and off quite fast and does the "heat adjustment" by increasing or decreasing the time they are in the "on" state)

The complete circuit only cost a few quid but unfortunately is just slightly too big to fit in the black box I used for the switch

I have bought another set of heat pads which I'm going to try and make a velcro together "pad" for and use them on the outside of the grips as I'm a bit dissapointed in the lack of heat coming through the bar grips I currently have on there (even when set to high)
The low setting is barely perceptible with my gloves on and stationary so is a bit redundant TBH

Regards
Rob
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tahrey
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PostPosted: 05:21 - 07 Jan 2011    Post subject: Reply with quote

Think something might be wrong there then! I haven't got to ride with mine yet - I'm busily still making a complete pig's anus of the leccy side of the install, after only just getting them physically on, and at 5am have decided to call it a night after somehow shorting 3 fuses (better them than the expensive bits!) AND fusing the relay "on" - but I have got them on the bike and had wired them to live power, and full heat means they start getting toasty to the touch (bare skin) in under a minute. Quite impressed Very Happy ... we'll see if it stays that way once i've nipped into halfrauds to get another relay and a box of fuses, assuming I don't get locked into works' overspill car park that i was hoping to avoid during the main carpark's imminent closure by riding.

Bike seems to be making enough watts once revved up to cruising rpms, but the effect of the PWM can be seen at idle through the (slight!) dimming of lights. It's almost like an indicator flash on min power, then gets higher and higher duty until level 4 (of 5) is indistinguishable from 100%. So unless its doing something wierd like alternating which grip gets the power, even the lowest setting is like 40-50% duty cycle. So it may explain why 25% is so lacklustre?

(Also think of it in terms of electric fires or fan heaters... 2-bar / 2000w setting will get the chill off, but the maintenance setting is only half that and can still seem a touch cool. 500w would be almost unnoticable)
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robocog
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PostPosted: 12:06 - 07 Jan 2011    Post subject: Reply with quote

Should be taken direct from the battery- so there should be no PWM going on

If you are stuffing AC through the relay that would indeed give it a headache and would quite possibly weld the contacts in the on position! (or kill it very quickly) and would possibly explain the fuses letting go

Wire direct to the battery only

Stick to DC as per the diagram!

If you are wired direct to the battery it could well be your reg/rectifier has gone
Needs sorting (and you'll probably need a new battery whilst your down there) Batteries don't like AC much IME

Regards
Rob
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tahrey
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PostPosted: 19:38 - 17 Jan 2011    Post subject: Reply with quote

Nono mate... you misunderstand. I haven't got the cheapy-cheap direct connect ones. Though I was interested in how your diagram worked, it's not actually of any use to me at this point.

Given how long a delivery time was stated on the cheap grips, I ordered up some more expensive but quicker-delivered ones, not knowing then how long it'd take to get them on and hence how little use I'd get out of them in the brassic conditions (heck, thanks to having to carry a lot of stuff and not wanting to be out in the wet til I've scraped all the salty shite off of what is hopefully a surviving layer of protective wax, haven't even used them for commuting yet). May as well have had the three quid ones!

Said more expensive "R+G" grips come with a little electronic controller dongle with five LED-indicated levels on, and the parts for screw-clamping it onto the bars. After the mentioned false starts (all the issues were because I was being a plonker and shorting positive to frame whilst the battery was still connected), I've wired it up proper:
short run of wire from battery to new fuse holder, then run up under the back of the seat to the (new) relay with a crimped and insulated spade connector, whose switching input parasites off the indicator relay high-power input with a crimped butt connector (lol butts), switch signal sinking direct to ground (at the battery... couldn't find a better ground clamp) and power output running back the same way, gorilla taped on top of the factory loom as far as possible, past the battery and up to the bars (again intermittently taping onto the loom, or where I had to make a loop because of excess wire, cable-tying onto the support hooks the loom uses).
At the bars, the power feed has a pre-installed waterproof clip connector to the dongle and similar back out to the grips themselves... which are also on quite long, clipped wires, which "for now" are coiled and cable-tied around an out-of-the-way bit of the bars.

They actually work pretty well, I had a run out in exactly zero temperature air, eventually up as fast as the bike would take me (65 ish with the silly milkbottle deflectors on) and came back with cool, but fully sensate digits, which is a definite improvement. In the end I was running them at full blast, but for most of the ride I had them on the lower 3 settings til the airflow proved too much for that; figure that if I'd left them on full all the way the result would have been better. Probably wouldn't be so great on a faster bike, but if I had such a beast I'd probably also invest in fairings/screen, better gloves, better deflectors... better hotgrips...

As it stands, for a piddly 125 and such cold conditions (about as cold as I'd dare max it in - when it was truly brassic I didn't ever get above 60, and rarely much over 25), and given how frozen my hands have got before, they did well.

The only problem I've actually found - which you wouldn't get with the stick-on elements - is they're too narrow! Never mind "if they're too long you can trim them to fit", they must be at least a half inch narrower than stock, there's a noticable gap inboard of where they end vs the flush look of the factory grips. I've had to put insulation tape around the exposed bit of the throttle twist to disguise and smooth it some. Trying to keep a decent grip on them did make my hands ache slightly. But it might just be a matter of getting used to a subtly different position - I seem to recall having a similar issue the first couple times I ever rode the CG, and it eventually wore off. Plus I would have been gripping pretty tight to soak up all the warmth. At low settings in the current milder air it may not be so bad. It's not like I'm going to get them off without cutting anyway (or getting hold of some dry ice), they're a SUPER tight fit, i'd almost suspect I had 1" bars and they were made for 7/8", if it wasn't that one side seems to have a rigid plastic inner section...

Anyway as far as the PWM goes, I can't see how else this setup would be regulating the heat output unless there's some fancy diode-and-resistor network hidden in the grips themselves, or it does a version of the series/parallel hookup electronically (which would be a flavour of PWM anyway, in order to give 5 levels). There are only two wires going to each grip, and no "dump" resistor/regulator that I can see. Plus there's the whole thing of the headlamp dimming slightly at about 2Hz (like an indicator with a blown bulb) on idle and low settings. It's not a problem of hooking it up to AC, or the bike's reg being blown, anything like that, because I'd expect to see the effect with the grips fully off or on 100% power (it stays steady, though dimmer when they're on), and the AC component is surely a whole lot higher frequency given that it idles around 1200-1500rpm and has a 3-phase alt...

Incidentally the battery was in fine fettle when I got back - certainly a whole lot better than when I started, where I almost flattened it leaving the LIGHTS (but not grips!) on whilst getting the garage tidied up and had to bump-start. (Why did they remove the kickstart?). Even though noodled back at 30-ish for the final few miles, with the grips on full blast, a test ignition-off/restart cycle at the end of the trip went off without incident.

Right, next job is to chop a bit out of the patch and reinforce the left hand deflector, as the clutch lever stuck on it a couple times during that run. Didn't do originally, must have stretched in the wind or something. Only needs like a millimetre's extra clearance. Hey ho...
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tahrey
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PostPosted: 20:33 - 17 Jan 2011    Post subject: Reply with quote

Or in other words ... seeing as you were so nice to give us a diagram before... here's my full layout Smile --- Hopefully it'll be useful to anyone else trying to figure out how to do it, as I had to cobble my knowledge of this together from various different posts and internet articles. The main one being the very fine grip-install (with photos) thread on this very board, whose author I'll name once I get back to the PC where I've still got it open! It didn't however have a diagram on it...

In this case the relays are under the seat, on the right hand side, WAY up at the back on my CG, and the red cable from relay to grips is actually run pretty much right across the top of the battery but for the little flange that the main loom also sits in. Your components may end up scattered in other positions so feel free to rearrange this.

Anyway, if you erase the inbound and outbound clip connectors for the controller and the controller itself and substitute in your own hi-lo switch diagram as before, it should look pretty much the same overall. May need to alter where the earth wire goes to or a couple other details (eg where the +ve feed comes from?) but there's not a great deal to the thing really.

Oh yeah and hopefully erase the pile of fried or hamfistedly mashed components...

(What can I say ... I haven't dealt down-and-dirty with automotive electrics for years, and this is my first time crimp/spade-connecting anything EVER. I didn't even know of it as a method for attaching electrical stuff until recently and I can hardly believe no-one mentioned it before - feel like a RIGHT noob. I would otherwise have been trying to solder or scotchlock/screw-block/wire-wrap'n'duct-tape this stuff... gawd! As it is, I used the cheapest of all cheap and nasty my-first-crimper kits from Halfords bargain pile, but it appears to have worked OK)

Red wires are "hot", (potentially) high current ones; blue wires are low-current positive for triggering switches; black wires go to ground (mind that although most of the voltage is spent, they still carry current, and that's what hurts!*). Naturally, it is NOT AT ALL TO SCALE Mr. Green
* May or may not be bullshit, but that's no reason to be careless.
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thenosabokid
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PostPosted: 20:24 - 19 Jan 2011    Post subject: How many watts do they use Reply with quote

I want to put them on my bike but Im concerned about how many watts they use

does anyone know?
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Im-a-Ridah
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PostPosted: 15:36 - 20 Jan 2011    Post subject: Reply with quote

robocog wrote:
Was thinking along the lines of using pulse width modulation (turning them on and off rapidly and varying the ammount of time they are on for) to control it, rather than dumping it elsewhere

More for the sake of doing it/an experiment more than anything TBH

Just unsure if those cheapies will actually get hot enough to justify it
(eg if they get mildly warm at best, no point in building a device to turn them down..LOL)

Will order a set anyway at that price

Regards
Rob


You'll need to use a transistor of some kind, a MOSFET would probably be your best bet in efficiency terms. If you are using a voltage controlled oscillator circuit like a 555 timer then you should be able to drive the MOSFET from the output. If you use a microcontroller you'd be best off putting a MOSFET driver in series for several reasons. Firstly, the MOSFET isnt going to be fully on until 6v or 7v, microcontrollers put out about 4.5v, so the on state resistance (and so the power wasted as heat on the MOSFET) is going to be larger. Secondly, a driver provides a source of high current, as MOSFETs draw a current in spikes, which a microcontroller can't supply, and so switching would otherwise take longer, and so your switching losses (as heat) will go up. Personally though, I'd just get a controller premade from China Thumbs Up
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herulach
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PostPosted: 00:31 - 21 Jan 2011    Post subject: Reply with quote

Should have posted up my findings too. I have mine wired to a control robbed from an old set of tech7 grips, as far as my multimeter can tell this is a pwm rather than voltage regulator.

With it on hot the grips get warm enough - not as hot as some, but certainly hot enough to make a difference (been out in -5 with these and a set of HG lobster gloves with no issues for first half hour or so, started to get chilly after that).

Turning it down to mid makes them hardly noticeable, probably just enough to take the chill off if wearing thinner gloves in the autumn/spring.

I did find a couple of wraps of insulation tape under the left pad made it heat up significantly quicker, otherwise you have to wait for the entire bar to get warm before your hand does!
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tahrey
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PostPosted: 22:40 - 07 Feb 2011    Post subject: Reply with quote

thenosabokid: without sticking an ammeter (or multimeter) in series, it's hard to be sure, but the symtec ones shouldn't be ANY higher than 3A (36~42w) at full blast (and probably a little below anyway) just as mine are under 4A (48~56w) at max - because of the fuses.

my testing does suggest that whatever it is, it's within the general spare surplus charge coming off an electric-start CG alt... If you figure you have 40w to spare, you should be OK. Even if the headroom is actually 41w and you go around with it on full blast ALL the time (which you won't unless you're blatting through minus temps at full throttle), it'll still trickle charge the battery enough. once you turn them onto part power it's probably no longer an issue.

Im-a-ridah: I figure that's pretty much what's going on inside mine, with some kind of very basic microcontroller taking the place of the 555. Nothing with any kind of fanciness, just enough to drive the mosfet subcircuitry at the set level, respond to the button / voltage input, store the last used power level in a single nibble of flash ram (might even be mag-core or bubble...) so it comes back in one press, and drive both the constant display and the other indicator patterns on the LEDs (a "i'm alive" knightrider pulse at first turn-on, a confimatory flash of the set power level after the button's been left a few seconds, etc).
There's nothing to PWM after all; something to drive the power signal on and off and control the width of the pulses, one or more power transistors (ie the mosfets) and the power source & sink.
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