1977 z650b1 project with pics [completed!!!]

The rectifier I have has Mitsubishi DS10TR2-M C9Y written on a sticker. C9Y looks to be a date code but I am not sure

That's the same rectifier that was on my 77 650 B1 when I got it, ran and charged perfectly for 5 years before I swapped engines and went with a permanent magnet setup.

You're probably right that it's a date code or maybe a batch no., mine is marked C06.

So you are saying the rec I have will work with both bikes as long as they are 3 phase regardless of permanent magnet or excited field?

I think they will - I'll ask Lou to check this thread, he knows what he's talking about.

Yes, the 900 with seperate reg and rec can use the same rectifier as the 77 650 which also has the seperate reg and rec, even though their regulators are completely different as detailed by OnkelB.

The 900, even though it originally had seperate reg and rec can use most modern 3-phase reg/recs from bikes with 3-phase, permanent-magnet alternators. There are also many aftermarket combo reg/recs which will work.

The 77 650, unfortunately, has to retain seperate reg and rec since there is no combo unit for this setup (that I know of). Oregonmotorcycleparts.com has a reg specifically for the 77 650 and the ones I've dealt with seem pretty good, especially if you consider how affordable they are.

You can make just the rectifier pretty easily.

Wow thanks for all the info everyone! This has really encourage me to do a lot of studying.

So basically, we have reached the conclusion that on a z900, which is permanent mag setup, you can use any rect as long as it is 3 phase. My question: Does that also apply to my 650? Can I use any rect as long as it is 3 phase? Since my new reg/rect is a combo, does that mean i cant use it at all? Would i be able to just ignore some of its wires and use it in conjunction with my old reg.?

It sounds like the 650 will take the same rec that the 900 uses but the 650 has to have its own regulator for that bike. The combo unit will NOT work on the 650. I think that is what was said

Yes, both 900 and 650 can use any 3-phase rectifier, as long as they are using a seperate regulator.

Usually, you would not use a combo rec/reg just for the rectifier portion. However, there is small chance you can use it as just a rectifier. If the combo rec/reg uses a dedicated sense line to detect voltage, you could leave that wire disconnected (or possibly ground it). Then it will never do any regulating, but will still rectify.

If the combo unit has no dedicated sense line, and, thus, senses battery voltage through it's output wire, there is no way to disable the regulator. You would not be able to use this type for rectifier-only duty.

Since your new reg/rec has that extra brown wire (assuming it uses KZ color convention), there is a chance you can use it as just a rectifier.
Do you have any literature or instructions on the reg/rec unit you bought?

Thank you to all for the help. I really learned a lot about rectifier. I think i figured mine out, but not sure. I need to get the carbs finished so that i cant start the engine and test it.


*******Does anyone know what the stock jet sizes are for this bike? (1977 z650b1) Although it is the japanese model, i think it has the same carbs as shown in the pictures above. They are the round type Mikuni brand. My original jets are so corroded that i cant make out the number on any of them.

#15 pilots, #102.5 mains, needle clip in the 4th groove (counting from the blunt end of the needle) is the stock setup.

Just a note here, that rectifier was a breeze to build.

Qdude wrote:

Just a note here, that rectifier was a breeze to build.

-care to elaborate?