New to DTT, and starting a '73 CB125 cafe build!

Sorry to bump but I've been digging around for 125 threads and I like the way yours has turned out! I have a '75 myself – I ordered a k&n/bigger jets not more than an hour ago and I'm planning on doing a 12v conversion down the line as well. Got any more pics/progress updates?

I really haven't done much since my last update due to school and laziness. Last thing I did was update the wiring diagram for 12v, which is attached to this. The GY6 reg/rect wiring can and probably will be different so you'll have to test it to confirm if you go that route. Good luck with your build.

I think I've finally got the jetting close. Using a Keihin PC20 clone, #78 main and #35 pilot. The clone was weird and I couldn't find any pilots which were an exact fit, so I ended up going with a #35 version of the exact same pilot in the stock carb.

With looking at the diagram, looks like you did a 4 prong reg, was there a reason? I'm noticing there are many different variations of the GY6 reg when it comes to the amount of prongs (I've seen 4,5,6,7)

Steaksauce said:

With looking at the diagram, looks like you did a 4 prong reg, was there a reason? I'm noticing there are many different variations of the GY6 reg when it comes to the amount of prongs (I've seen 4,5,6,7)

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The CB125S generates single phase AC and 4-prong GY6 regulator/rectifiers are all single phase AC to 12V. It also happened to be the cheapest on eBay at the time...

3-phase example: http://www.ebay.com/itm/12V-6Pin-11Pole-DC-Voltage-Regulator-Rectifier-for-GY6-150cc-Scooter-ATV-GO-KART-/181404874358?pt=Motorcycles_Parts_Accessories&hash=item2a3c92b676&vxp=mtr

That one has three yellow wires, a red, a red/white, and a green. Typically the yellow wires are your phase leads and in this case three leads = three phases. The red is usually the bike 12V+, red/white is usually battery 12V+, and green is ground.

Single phase example: http://www.ebay.com/itm/Voltage-Regulator-Rectifier-4-Wires-4-pin-12V-for-GY6-scooter-ATV-50-125cc-150cc-/321403550852?pt=LH_DefaultDomain_0&hash=item4ad524fc84

The four wires on this one are yellow, pink, red and green. Yellow and pink are your AC in and can correspond to the CB125S's yellow/pink (make sure to jumper the yellow and white wires from the stator!). Red is 12V+ and ground is green.

Ah alright, thanks for explaining that. Wiring is a bit of a weak spot for me lol

hey why did you end up scrapping the sv650 hanger and caliper.

BravoTango said:

hey why did you end up scrapping the sv650 hanger and caliper.

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It looked like it would be easier to use the Ninja 250 front caliper. Someone here on DTT was looking into or already had made a bracket which used a Ducati Monster rear caliper.