Newbie w/ tc125 elect problem

[ANCIENT TC125]

I recently purchased this 1974 TC125 which I thought was in mint condition.

Everything works great, but it keeps blowing out the headlight (very expensive). Have read most of the other posts on the TC 125 and TS125 about the voltage regulator but I can't find one on this bike. Not under the resistor nor on the front Yoke. The wiring chart with the owners manual doesn't show one. The parts outlets do show one but very expensive.

Question
Where should VR be on this bike (or if)

Anybody have an accurate Wiring Diagram

Anybody have suggestions for aftermarket VR

Help muchly appreciated

Steve

[jabcb]

Is your bike 6 or 12 volts?

[ANCIENT TC125]

THE TC 125 (1974) IS A 6 VOLT. THE LIGHT CIRCUIT IS PUTTING OUT 14 20 VOLTS AC

[Alan H]

The battery is usually the voltage regulator unless its direct lighting, but if you can post a wiring diagram we can see what is what. It's unusual for a regulator in a 6v circuit. The old Zener diodes were 12v.
Open circuit voltage, i.e. with no load, is always higher than when it is loaded up with (say) a bulb.
Most common issues with a directly lit circuit - straight from a lighting coil so it isn't too bright at tickover, and gets brighter as revs rise, are either a bad connection or buld too small.

[Alan H]

https://uk.search.yahoo.com/search;_ylt ... ng+diagram" onclick="window.open(this.href);return false;


Looks like it's direct, so make sure the bulb is correct wattage, and ALL connections are good, especially earth and dipswitch.

[ANCIENT TC125]

TC(&TS) 125 WIRING CHART HAS A EUROPEAN VERSION (LIGHTS ON, LIGHTS OFF COIL), AN ASIAN VERSION, AND A USA/ CANADIAN VERSION.

THEY ALSO CHANGE BY YEAR

I HAVE THE EARLY 70'S AND THE 77( I THINK), BUT I AM LOOKING FOR THE 73-75

TNX

STEVE

[ANCIENT TC125]

OK, I FOUND WHAT I BELIEVE TO BE THE CORRECT WIRING CHART ON THE ROAD BIKE BOARD:

http://www.flickr.com/photos/zunspec/35 ... 167314563/" onclick="window.open(this.href);return false;

THANK YOU Zunspec4

THIS LAYOUT HAS THE MAGNETO RESISTOR BUT NO VR. FROM WHAT OTHER VERSIONS I'VE SEEN THE VR GOES WHERE THE BLACK/WHITE WIRE TEES OFF THE RESISTER LEAD AND GOES TO EARTH GROUND.

HAVE TO PUT THE BIKE BACK TOGETHER AND RECHECK VOLTAGES I'M GETTING AT LIGHT, BATTERY, ETC

ANYONE HAVE ANY IDEA IF THIS LIGHT SHOULD WORK ON THE TC 125 (1974)?
http://www.amazon.com/gp/product/B00GNU ... CAHSVQHA4B" onclick="window.open(this.href);return false;

THE STOCK ONES ARE TOO EXPENSIVE AND HARD TO GET!

TNX

STEVE

[ANCIENT TC125]

BY THE WAY SUZUKI LIST THE VR AS ITEM #24 HERE:
http://www.suzukipartshouse.com/oempart ... el-magneto" onclick="window.open(this.href);return false;

32500-25600

THEY GO FOR $142 TO $170

FROM WHAT I UNDERSTAND (AND I DON'T) A ZENER DIODE SELLS FOR DIMES AT RADIO SHACK?

IF ANYONE ACTUALLY HAS THE SUZUKI VR 32500-25600, IT WOULD BE NICE TO FIND OUT THE PART NUMBER ON THE DIODE (FOR OBVIOUS REASONS).

[Alan H]

No need to shout! All capitals mean shouting!!!

[jabcb]

A 6V mixed AC/DC electrical system was fairly common.
There are some aftermarket 6V AC voltage regulators that should work.
I've seen some posts about this, but it will take some digging to find them again.

Looks like Rex Caunt has a 6V AC voltage regulator that should work.
http://rexcauntracing.com/pages/regulators.html
http://www.ebay.com/itm/YAMAHA-XT500-DT ... 0165796372

Rex's regulator is about $45.
Its worth sending him a email to confirm that it will work.

[jabcb]

I found a posting about upgrading a Honda 6V mixed AC/DC electrical system.
They used a 6V regulator/rectifier.

See part 6V_reg_rec @ http://www.dratv.com/6voregre.html
Will also need the wiring pigtail, part # SUB-W-12/12/6/6

From their site:
"THIS ONE ITEM CONTROLS THE HEADLIGHT VOLTAGE (AC 6 VOLTS) TO KEEP THE HEADLIGHT FROM BURNING OUT,, AND IT GIVES THE BATTERY PLENTY OF 6 VOLT DC TO KEEP IT FULLY CHARGED AT ALL TIMES."

Honda used different wire colors.
Here is wiring diagram for Honda:
http://ep.yimg.com/ca/I/dratv_2268_41388744

This solution might not be good for the electrically timid, but its worth considering.

[Zunspec4]

Hello Ancient,

Glad my TS125 wiring diagram was of help. My particular 125 variant does not have a separate voltage regulator. It would appear that the regulation needs a GOOD battery in circuit. I let my battery die through lack of use and then had bulb blowing issues when I got it out again. Replaced the battery and all good.

I have an official Suzuki workshop manual for the 125 which includes other market diagrams. What is the exact year/country of your bike I could maybe scan the applicable cct diagram an email it to you.

Cheers Geoff

[ANCIENT TC125]

GEOFF

Thanks for you response. I am in Centerville, Utah, USA. I have a 1974 TC 125. I have a web copy of the early 70's service manual and a 1977 version. Both seem to be slightly different than my bike. The bike came to me with a blown headlight so I tried to save a little money and bought a 6 volt 35 watt headlight off amazon ($9us versus the Stanley Suzuki if you can find one $62). It worked at idle but at rev it smoked it. Then tried a 12 volt old sealed beam of a Vanagon. Same thing. Did some voltage checks to see what the output at the light connection was and got crazy reading DC and 14 to 24 volts AC. I guess I could buy a 18 wheeler sealed beam but obviously something is amiss here. The Headlight bulb is the only bulb that is blowing. Brake, instrument, and running lights fine.

Ripped the bike down to the frame to try and see if I could find the VR but to no avail. The resister and Rectifier seem to check out. Brand new battery fully charged. Now in the process of rebuilding the bike to run it again and check voltages.

Fascinated with this zener diode concept: http://www.electronics-tutorials.ws/diode/diode_7.html" onclick="window.open(this.href);return false;

Looking on the wire diagrams for the TC bikes that have these, they seem to connect with a single wire between the tee lead off the common or negative (black/white) circuit where it goes to earth ground. I'm assuming that is where the Rex Caunt unit single wire would also connect. Anyone have any info on this?

Check back with you when I get this back together and can retake voltages.

Thanks Again

Steve

[jabcb]

The Rex Caunt link I provided is for an AC voltage regulator.

Your headlight operates on AC.
The AC voltage regulator's single wire connects to the wiring between the headlight on/off switch & the headlight low/high switch.
The AC voltage regulator must also be grounded via its mounting bolt.

[ANCIENT TC125]

JABCB

Thank you for your info:

The following are two wiring charts for TC125 (USA)

This one is out of the 77 service manual(I believe)

http://suzukits.informe.com/gallery/TS1 ... 4.jpg.html" onclick="window.open(this.href);return false;

Note where they put the VR. It is a little hard to distinguish which wire they are labeling, i.e., the gray going to an box something then bl/wht, or the earth ground from b/w. Any ideas which is which?

This one I got from Zunspec4 on the road bike board. It appears to be for the 1974 or my bike

http://farm4.static.flickr.com/3620/352 ... e702_o.jpg" onclick="window.open(this.href);return false;

No VR just resistor and rectifier.

Anyway, I've had an epiphany(?)
I don't really want this bike as a road bike. I bought it to explore mountain trails. That's why I wanted the hi/lo tranny. If I can't get it to operate as currently wired, what is to stop me from just taking a wire from the battery to a cheap three way switch (off,on, hi, low) then to a new model halogen
(http://www.amazon.com/gp/product/B00GNU ... CAHSVQHA4B" onclick="window.open(this.href);return false;)
or LED headlight. It would be very rare for me to use a headlight. In addition I would not be spending hundreds of dollars on old, used, or nos parts. If the battery is not large enough , I could just go up one or two levels. What's wrong with this logic?

Thanks In Advance for your inspiration and Ideas

Steve