Changing from 6V to 12V

[Jerry D Fast]

I have a 76 TL250 Honda trials bike and would like to switch it to 12V, does anyone know what that intails???

[Dwight_Rudder]

WHY ? I really doubt that you can anyway. But, really, WHY ?

Dwight

[zbnutcase]

EXACTLY!! WHY????? 'nutcase

[resurrection]

It' common with the BMW crowd .

new Regulater ,battery, change bulb sockets and roll.

[wayne huff]

Pardon my ignorance but does the TL have a battery system? If not it would be easy enough but as Dwight said, why bother? As long as you can get 6V replacement bulbs just stick with what you got. need more info to help, wayne

[plugeye]

i'm thinking about doing that to my old thumper too.

there are some articles on the internet about rewinding the lighting coil

the reason i want 12v is for better lighting

[Jerry D Fast]

For the 6" sealed beam headlight I have, there are limited choice of 6V bulbs,also I am putting one of these TL250s in a 2000 XR 400 chassis, with all 12V bulbs.Well it keeps me off the streets.

[Jerry D Fast]

The TL does not have a battery,rectifier or regulator, it has only a mag/ with a lighting coil.

[plugeye]

that makes it easier. find the articles to rewind for 12v then you might want to add a big capacitor for surge suppression. on my 79 XT500, i currently run no battery with 6v lighting coil, capacitor, stock regulator, stock rectifier, stock 6v headlight & 12v LED 1157 taillight. no issues except for dim headlight.

[KDN]

Of course you can. And I agree with you - better / better choice of lighting.

I'm not quite clear on your intentions, as I thought the TL was a trials machine, rather than much intended for nighttime street or trail riding. But, I agree with the desire.

So, rewinding the lighting coils is pretty straightforward. Unwind the stock, rewind with slightly heavier wire, with as many neat, tidy, tight wraps as you can get.

Wire the output to a bridge rectifier to convert to DC and add a battery if you want, or use a capacitor setup as mentioned.

That said, there are precedents for just swapping from 6v components to 12v components and let 'er rip. Many folks have been claiming that the 70's Honda singles will output enough to keep a 12 volt battery charged and the lights well lit, as long as you keep the revs up out of the basement a bit.

I haven't done it myself on a Honda single, but I did do exactly that on a '78 Honda CM185T street bike I owned once. A pvs. owner had mistakenly put a 12-volt battery in it (it was a 6-volt bike), and blew all the bulbs out. I got the bike for free and simply added 12-volt bulbs all 'round (headlight, tail/brake light, dash bulbs, blinker bulbs) and it worked like a champ for another 10,000 miles. The electric starter ran a bit faster than normal, but that was the only difference I could ever detect.

Good luck with it.

Kirk

*edit* here's some reading for you: http://xlboard.aimoo.com/SL-100-125-s/Stator-Rewind-to-12-Volts-Foll-1-999410.html

[wayne huff]

Before you go to rewinding coils etc, try what I do. This works and has been proven on many bikes. Get a "Moose" 12V regulator Parts Unlimited # 2112-0090 They are less than $15. Then simply switch to 12V bulbs. There is plenty of AC to run the more efficient 12V bulbs. It is simple, cheap and you can forget about 6V. You will have good lighting even at low RPM and will have a very reliable system. I have yet to blow a bulb and have very good lighting. The mag does not need to be rewound to have12Volts!!!! THIS WORKS good luck, wayne huff

[wayne huff]

Hi Thumper folk. It is very easy to convert to 12V on these old bikes. In the old days regulating voltage was a hassel. They used high resistance 6V bulbs to do most of the regulating. With modern solid state regulators it is easy to convert to 12V. Just purchase a 12V regulator like the " Moose " 12V HD regulator. less than $15, install it ( easy two wires and one goes to frame ).

Then install 12V bulbs and you will have good basic lighting for enduro type or off road vehicles. There is no need to rewind for 12V because the output of most magnetos is about 20 to 30 VAC at just above an idle. 12V bulbs have a lot less resistanc than 6V and will be brighter. I have done several now and this has been tried by other friends and with great results. I have been using this on several bikes from Hodakas to SL100 Hondas. If these regulators were available years ago there would not be many 6V systems. The regulator I have been using is the Moose Parts unlimited # 2112-0090 anda should cost less than $15 from your local dealer. TRY IT ! it works very well, wayne huff

[KDN]

Hey, Wayne,

That's great info. I have both a Hodaka 250SL and several early SL/CL Honda 100s and 125. I've read about doing it, but it's always been "my brother's roomate's cousin knew a guy who..." ?

I'm curious about the hookup: the early Honda's are two wire, where each wire is one end of the long multi-coil charging/lighting circuit. Each wire goes to half of a full-wave rectifier, which inverts half of the DC. With the Moose type, with a single input and one side grounded, it must just be a half wave rectifier, which just clips that other half. Where do you hook up the second wire from the OEM system?

Anyway, sounds interesting. I may give it a try...

Kirk

[wayne huff]

Kirk, forget about rectifiers and DC current. The regulator simply plugs into your lighting wire and the other other wire has an eye made on to it, that goes to ground. If you have two wires coming out of the mag( other than the wire for ignition) just use one of them. the other may need to be grounded but I think it usually can be just taped off or something. This is something I have tested and currently use and is not some rumor. It works and works well. If it matters to anyone, yes I do have a degree in electronics and am a long time proffessional motorcycle mechanic. The regulator is small and bolts to the frame. prefferably where it can get air although I have had no over heating problems with the ones I am using. The regulator works so well it is impossible to tell when it kicks in and doesn't seem to care what rpm or load you put on it. I know this all sounds too good to be true but the availabilty of a good cheap reliable regulator has changed everything about simple reliable lighting on these vintage bikes. I say again, you do not need to rewind for 12V. The windings are already wound to produce enough AC to run 12V bulbs. I know it seems backwards but the 12V bulbs have little resistance and do not put near the demands on your magneto output as 6V bulbs and rectifiers.I will try to write this up in more detail and post it on my web site when I get around to it so I won't have to do it for every forum I am in.By the way, Dwight Rudder is using this method on one of his bikes that I wired for him and is well pleased. Also this is so much fun to get rid of the corrosive battery,unreliable rectifier and there is no need for a fuse!! Just a light switch and a kill button. Try it you will like it. have fun ,wayne huff

[wayne huff]

Kirk, The early Honda SL100/ 125's will not run without a battery and will have to have my "No battery conversion" before you can take advantage of the AC only system. The other magneto powered two strokes and later four strokes will work with simply doing what I said and using the regulator and 12V bulbs. wayne

[inthedirtagain]

Holy Crap!!!! I have searched and searched for the answer to this very question for the last 3 days. Every website I've been on is saying that I need this and I need that, and it will cost $$$$ to get it done.....whew!

I want to convert my 1985 XR350R to 12v and run some LED brake lights and turn signals. You just answered a question that my Clymer's manual could not. The wiring diagram states that a regulator and 12v lights were factory options, but doesn't go into any details! Now, I'll just head to Canyon Honda in the morning and order up my regulator and peruse their options for aftermarket lighting. Thank you so much:thumbsup:

[willie]

Many years ago I converted a Kawasaki F9 from 6 to 12v the same way Wayne describes. Worked great. Removed regulator/rectifier/battery/6v bulbs much of the wiring and replaced with a 12v ac regulator and bulbs. Much simpler and reliable. However you may have trouble operating DC specific items such as signal light flashers, horns and led lights. If you want to use these a full wave DC or bridge rectifier is required in addition to the regulator.Also you will need a large capacitor for signal lights. Added complexity but certainly possible. Have seen 12v rectifier/regulator combo units for $80+ several years ago but may be cheaper now.

[wayne huff]

Willie is right on. My 12V conversion will not support any DC applications like LED, turn singal flasher etc. It is for total AC and works well with basic lighting, head tail, brake light.

wayne

[KDN]

Ah, there's the big stumbling block, right there!

My intention all along has been to convert 6V to 12V and still maintain all street equipment - horn, blinkers, dash bulbs, etc. It was never my intention to make a simple 'lights only' deal, or to try to eliminate the battery or rectifier.

Thanks for the clarification on that!

Kirk

[Madmac74]

Wow, this is great info. Just to clarify; I have a '83 XR 200 R, with just head and taillights. Its got the 6 volt system. If I understand correctly, all I have to do is get the Moose regulator, and 12 Volt bulbs??

Thanks Wayne Huff much appriciated:applause: ?

MAC in Prince George