DT 175 MX 12volt conversion

[nydamon]

Signals work perfectly. I'm using an electronic flasher that is not load dependent so it will run LEDs or even work with only one incandescent bulb per side. The stock 6v relay worked but made a funny noise and blinked too slow.

[teledan]

Cool, I have an electronic flasher also. I think I mut have a bad ground somewhere or something.

[teledan]

I tried grounding my LED turn signals straight to the capacitor (battery eliminator) and they still don't work well under about 2.5k rpm. I'll have to do more troubleshooting on that but the tail light and head light are great!

[nydamon]

I didn't think there was enough power to run turn signals without a battery. I know incandescents won't work.

[teledan]

I know of people that use battery eliminators on SRs and XTs and the turn signals work fine. I think mine will work well enough to pass inspection though.

[NE0]

I Had to replace a blown tail light bulb the other day, first time since the 12v conversion. Which is not bad after over 18 months of use. (I did blow a speedo bulb at the beginning but it was 2nd hand to start with)

This led me to develop a way of monitoring the replacement bulb (as i was unaware it had blown)

read about this project here.

[Dt175]

Currently working on restoring a 1974 yamaha dt 175 E.

i want to do this 12 v conversion, apologies if ive missed where you explained it

but will the new 12 v system still be able to charge its battery with the gen?

[Airhead]

Currently working on restoring a 1974 yamaha dt 175 E.

i want to do this 12 v conversion, apologies if ive missed where you explained it

but will the new 12 v system still be able to charge its battery with the gen?

DT175E was 1978 and virtually the same bike as NEO's...a monoshock?

[Dt175]

yeah a monoshock. not generator start like the MX though, kickstart.

[Airhead]

yeah a monoshock. not generator start like the MX though, kickstart.

It's 1978 that was my point I know its not elec start It's virtually the same bike as mine and NEO's

[Dt175]

oh okay sorry, so it that a yes to thinking this process (i know if i mess it up i cant complain) will work in converting my DT?

thanks for your time

[NE0]

There's no reason why it shouldn't work on your bike,

Once all the bulbs have been replaced with 12v, the battery runs that circuit.

the bottom line is simply the generator charges the 12v battery and runs one headlight!

Whilst the coil is capable of doing the required work

The payoff is the headlight will not be as bright at lower revs ie below approx 3000.

Thats all this conversion is about.

.

[Dt175]

Thanks heaps mate this is my first project. got my new bulbs, battery and reg/rect on the way!

ill let you know how it goes

[mech73]

Hi

I've just been reading this project with interest as I have converted two FS1E's to 12V in the last couple of years. The FS1E has a very similar circuit to the DT's, however I used a different method.

I wanted to run the lights on DC direct off the 12V battery as then you get full brightness even at tickover.

The problem is that the standard rectifier (and a C90 cub one) are the 'half wave' type with a single diode, this means that only half of the ouput of the generator can be used to charge the battery. This would mean the battery would not be charged sufficiently with the lights on (assuming the wattage of the bulbs was the same as before the conversion).

My answer was to use a rectifier/regulator of the 'full wave' type which are readily available on ebay for the larger Chinese bikes. Unfortunately the lighting/charging coils on FS1E's, DT's etc are usually earthed at one end. For a full wave rectifier to work this coil has to be de-earthed, so the reg/rect can be connected to both ends. The diagram below shows the circuit I used.

This does need some soldering work at the stator and some modification to the loom. However you do end up with a simpler wiring circuit. When fully installed I checked it out using a meter strapped to the tank, measuring current into or out of the battery.

I initially tried with a 35W headlamp (std is 18W), but the break even speed for charging was 44mph in top which is almost flat out. I settled on a 25W halogen bulb where the break even speed was 25mph in top. I used a dry sealed battery from screwfix and it's never needed charging in over a year.

The second fizzy I did, I fitted a whole pattern stator intended for a PW50 kids bike. This was to get CDI instead of points. I wired the lighting/charging in the same way as before, but this coil was more powerful and easily runs a 35W headlamp.

This was the reg/rect I used it's a 5 wire type. The 5th wire goes to a 12V feed from the battery that is only live when the ignition is switched on. Otherwis the circuit is as above. From memory the wire colours were:

Yellow = AC Input 1

Pink = AC Input 2,

Red = Battery positive

Green = Battery negative (earth)

Black = Battery positive but only with main switch on

http://www.petrolsco...r/category/411/

There are loads of similar units on ebay, but the useful information is usually lacking and it's not easy to tell the full wave from the half wave and the single phase from the three phase. The one above definitely works though and regulates at about 14.5V.

Hope that was useful.

Cheers

Mark C

[Airhead]

Very good interesting post there Mark

[shntat]

i converted a 78 dt175 to twelve volt electric start. i got everything machined to make fit . just need brushes a spring and the regulator and i can then test the system out.

[busyeddie]

Neo, can you point me in the direction of the 45w bulb? Ive searched but have drawn a blank. I am doing this conversion over xmas I think, as my yellow DT is gettin used for night rides now so needs some light! If it goes well ill do the same for my blue one.

Cheers!

[NE0]

http://www.ebay.co.uk/itm/APF-12v-45-45w-Headlight-Bulb-/271087594212?pt=UK_Motorcycle_Parts&hash=item3f1e146ae4

Readily available, various prices!

These fit my DT.

[busyeddie]

Bloody hell NEO, that was quick!! Cheers mate. I assume back bulbs, instrument lights etc all fit ok, just 12v instead?

[busyeddie]

also did you consider using relays to power said front light direct from battery?? maybe with thicker cables?