Messages

1

Tech Talk / Re: Sanity check: The lay of lighting coil (or any other stator coil for that matter

« on: October 02, 2012, 09:51:42 pm »

yeah put the circuit up fo the 6 and 12v,i like playing around with electronics

Started a thread as requested http://ozvmx.com/community/index.php?topic=25750.0

2

Tech Talk / DIY 6VDC or 12VDC Voltage Regulator

« on: October 02, 2012, 09:48:28 pm »

All,

I've been putting into some research into alternatives for the lighting / charging systems for my Dad's PE400 and my DT175A.

I bought a cheap Chinese regulator/rectifier off ebay and wasn't having much luck so I poked around on the net till I found an elegant solution.



The above schematic is taken from this website http://www.reuk.co.uk/LM317-High-Current-Voltage-Regulator.htm

Modifications i've made to this circuit are:

- Include a bridge rectifier between the lighting/charging coil and the input of the circuit to get DC.
- The PNP Darlington transistor (shown as Q1 in the schematic) I used is a BD650 which is good for 8A of current. It's possible to use a different transistor if you require more current/wattage.

For 6VDC output use:

- Resistor R1 = 120 Ohms
- Resistor R2 = 470 Ohms

For 12VDC output use:

- Resistor R1 = 120 Ohms
- Resistor R2 = 1 KOhms - 1.2 KOhms

A 1 KOhm resistor is calculated to give 11.67 VDC, 1.2 KOhms will give you 13.75 VDC

For additional functionality/precision R2 could be replaced with a variable resistor or trimpot to provide more light or get more precise voltages, similar to a product that Trail Tech produce.

I've used resistors rated for 1 Watt to provide a bit of safety margin.
Remember also to get caps with adequate voltage ratings.
I mounted the circuit on some stripboard from Jaycar.
All components are readily available from Jaycar and can be had for < $15.

Note, that it's highly recommended to provide adequate heat sinks for the LM317T and the Transistor. I'll also be looking to pot these using an appropriate resin in the near future.

In order for the circuit to work correctly the supply voltage must exceed the desired output voltage by a 1.5 - 2V or so. So, if you're looking to change your 6V system to 12V ensure that your lighting/charging coil at idle produces around 14VDC after it's gone through the bridge rectifier.

3

Tech Talk / Re: Sanity check: The lay of lighting coil (or any other stator coil for that matter

« on: October 01, 2012, 05:55:04 pm »

Bit of an update:

Tried alot of things to get this home-brewed coil to work to no avail.
Possibly the gap between the coil's core and the flywheel is too great. The way dad has the stator set up is using one mounting hole for say lighting coil "A" and one mounting hole for coil "B" - straddling across the stator.

The path forward I think:

1) Either get a PE250 T/X or PE400 T/X coil - I've checked part numbers and it looks like that the are interchangeable - can anyone confirm this?

2) Or get a TS185 coil which will fit will a little coercing from a file - Can anyone also confirm this for me?

3) I've also been told that the following can be used but will require a new stator plate. http://www.rickystator.com/catalog/suzuki-lt500r-watt-lighting-coils-p-243.html

I've also scratch built a voltage regulator that i've currently got running at 6V and is good for 8A. I can easily change a single resistor to get 12V @ 8A if needs be - depending on what I can get out of whatever coil i can source. If anyone would like any info on making their own DC linear voltage regulator i'll be happy to start a thread. Only a resistor change to get your desired output voltage. Cost of build < $15.

4

Tech Talk / Re: Sanity check: The lay of lighting coil (or any other stator coil for that matter

« on: September 24, 2012, 06:43:22 pm »

If you fit a regulator you also need a largish capactor to act as a load to allow the regulator to operate otherwise it will almost certainly fail when the lights are turned off.

Again, thanks for the info Montynut! Most helpful.

5

Tech Talk / Re: Sanity check: The lay of lighting coil (or any other stator coil for that matter

« on: September 24, 2012, 12:22:34 pm »

you say it is lighting a 12v 21w tail light.
The PE250/400 lighting in _total_ was only about 20w of 6v. The headlight was 15, the taillight was 5.
Brake and blinkers were drawn off the battery.
Lighting coil should be putting out 5.6v->8.5v@8000.

lukeb1961,

I tracked down the owner's manual last night and yes was surprised to see the front headlight was only 15W. Thanks also for the output figures of the coil. Dad's going to track down a 6V bulb and give it a go.

Montynut,

That's interesting what you said about too much iron - i'll bear this in mind.

Regarding the drilling out of holes, also a good point that I didn't consider. The extent of modification to the holes was reaming them out about 1 - 2mm each to make them fit. I'll be sure to monitor that.

I'll report back once we have another crack. Meanwhile, i'll put a 6V regulator on order.

6

Tech Talk / Re: Sanity check: The lay of lighting coil (or any other stator coil for that matter

« on: September 23, 2012, 08:40:47 pm »

Thanks for your reply, Montynut. We never had an original lighting coil to work off unfortunately. We used the iron from an old pulser coil and an old ignition coil and sandwiched them together. Perhaps there's not enough iron.

I'm just digging out the PE400T manual now to get the factory Ohmage of the lighting coil.

The mounting holes had to be drilled out a little to make it fit on the stator - perhaps the gap is a bit too large at the moment.

When i say the multimeter was getting weird readings - it was sweeping between hundreds of volts AC to a handful and then back up again. I used a bridge rectifier to get DC and the same was happening. It was like it was getting interference. I tested my Yamaha DT175A coil the other week and it was reading fine at just around 7 volts at idle without a regulator so i know the meter works.

Proof is in the pudding i guess - glowing a 12V bulb at idle and a little brightness at half throttle.

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Tech Talk / Sanity check: The lay of lighting coil (or any other stator coil for that matter

« on: September 23, 2012, 07:11:16 pm »

All,

Just a sanity check on the lay of lighting coil - thinking back to my introductory physics course:

1) Shouldn't matter if i start winding the bobbin right to left give the coil will produce AC (not the case for a pulser coil of course where initial polarity is key)

2) Be consistent with the direction of lay - wind the wire, say, right to left then run wire parallel to iron core back to right side of bobbin and repeat. (Winding right-left, then left-right etc will cancel out any voltage being produced.)

Learnt the hard way, or rather, my old man did. He wound a lighting coil for his PE400, i must admit with my instructions "it shouldn't matter how, just wind it all on". Wired it in today and got some inexplicable readings out of the multimeter - and barely enough juice to power a 12V 21W taillight bulb. Went back to the drawing board and thought a little more and reasoned the above points out - i think i've got it sussed.

8

Tech Talk / Re: Yamaha DT175A (1974) Stator - What's the 3rd coil for?

« on: September 10, 2012, 07:39:16 pm »

More digging:

boats.net tells me that it appears to be a second lighting coil.

http://www.boats.net/parts/search/Yamaha/Motorcycle/1974/DT175A/FLYWHEEL%20MAGNETO/parts.html

Perhaps 1 coil is left as AC to drive the headlight directly, and the other is rectified and used to charge the battery and all the other lighting demands.

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Tech Talk / Yamaha DT175A (1974) Stator - What's the 3rd coil for?

« on: September 10, 2012, 07:30:19 pm »

I've started to tinker with my lighting coil. I removed it a couple of years ago when I first got the bike. After inspecting the stator plate yesterday I noticed there's two more tapped holes to accommodate another coil. I wrote it off as something Yamaha has done to economise spares, sharing stators for different bikes.

Then I came across the following image:



So,

- 1 off coil for ignition
- 1 off coil for lighting

What's the third one for, also ignition? Does it have anything to do with higher RPM's and sparking?

Why i'm so perplexed is that my bike currently starts and runs fine....albeit I haven't really opened her up except for a session at Barleigh Ranch where it was so out of tune it was oiling something fierce after a couple laps which i put down poor needle and mixture settings - I also didn't de-oil my air filter......

This makes me wonder if I need that additional coil??

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Wanted / Re: Wanted: 12V headlight, fork ears, front and back blinkers, flasher, tail light

« on: September 08, 2012, 10:09:24 am »

Have some fork ears, but can't remember if they came off Dt or TS185.

Yours for the postage if you want them.

Thanks very much SimonC, much appreciated. I'll send you a PM.

Blinker can is ~$9 from your local car parts place. Wouldn't bother with a used one for that sort of money.

Will have a look for other bits when I get home. 99.9% sure I've got a headlight with DT ears, but can't recall whether they're for the 250 (34mm) forks or the little 175 forks.

Also, thanks very much Nathan S and for the advice re: blinker can. Let me know how your search goes, either way i'm happy to buy the headlight. SimonC has kindly offered me some fork ears.

I see on eBay there are incredibly cheap blinker sets but I was worried that they wouldn't pass a roadworthy?

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Wanted / Wanted: 12V headlight, fork ears, front and back blinkers, flasher, tail light

« on: September 06, 2012, 08:58:04 pm »

Hi all,

Just after a range of lighting bibs and bobs for my Yammy DT175A. Going to get her road registered.

While i'm at it i'm upgrading, or should I say, making from scratch a 12V lighting system.

Please PM me if you can help out with any or all of the bits. I'm not too worried about aesthetics at this stage.

Cheers,
tdpomodoro

12

Bike Talk / Re: Road registering 1974? 1976? Yamaha DT175

« on: September 04, 2012, 12:12:43 pm »

Thanks to all who posted, fantastic information.

Currently my budget is only permitting me to buy odds and sods to hopefully get the girl roadworthy again.

It's a race between my L's expiring and getting a registered motorbike with which to legally ride on the road!

13

eBay Finds / Identify this bike

« on: August 23, 2012, 09:05:17 am »

Here's a twin-shock with very limited information. Can anyone identify it?

http://www.gumtree.com.au/s-ad/raymond-terrace/motorcycles/dirtbike-200cc-300cc/1005914072

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Bike Talk / Re: Road registering 1974? 1976? Yamaha DT175

« on: August 14, 2012, 09:59:26 pm »

Thanks for the great info Nathan S. Looks like i've got a '74 judging by your description:





I have a fair way to go to get her back on the road..... I'm slowly piecing her together.
Note the liberal application of heat wrap in the vicinity of my header repairs.

I'm not sure if the frame/engine number has ever been registered before. Is this going to prove difficult to get it through the RTA?

15

Bike Talk / Road registering 1974? 1976? Yamaha DT175

« on: August 14, 2012, 07:36:33 pm »

Hi all,

What's the chances of road registering my old 1974 or 1976 (hard to tell) Yamaha DT175 - Did Yammys of this vintage come with a compliance plate?

I have found the frame number stamped on the fork stem and the engine number is obvious. However no plate to speak of, or anywhere that looks like it had one attached.

I'm in NSW for the purposes of rego.  I'll post some pics when I get home.