Proud Owner of a KZ650

Hello everyone.

Last week I was gifted with a great condition 77 KZ650. Ive had older bikes all my life, but never a 650 until now.

What a great bike. Amazing power and very smooth. I have a few questions:

Is it me or is the choke finnicky on these things. My bike takes forever to warm up, and still needs a bit of choke every now and then. everything on the bike is stock, including the pipes.

All of the lights (brake, oil and neutral) worked fine until i let the bike get reallyt hot when warming it up. Its not a big deal, but while everything else including the oil light, signal lights and headlight are fine,

The Neutral light and Brake light no longer come on

I can find netural easy so i dont need a green light to come on to tell me when Im in neutral, but what could have caused the neutral and brake light not to appear anymore?

Beautiful bike! My 79 KZ650 D2 warms up unusually slowly. I've gone through the carbs and set it up with Gunson color tune and sync'd them, still warms up slowly. Just in case you aren't aware, air cooled bikes shouldn't just sit idling for extended periods. Without air moving through them they can overheat.

You should be able to access the oil and neutral lights quite easily. The beauty ring around the ignition switch just unscrews and the cover will come off. If you have checked the bulbs and the sockets, you will have to work backwards though the wiring harness. I strongly suggest you get a factory service manual. These bikes are fantastic and you have a brilliant example. Good luck.

ajsfirehawk wrote: Beautiful bike! My 79 KZ650 D2 warms up unusually slowly. I've gone through the carbs and set it up with Gunson color tune and sync'd them, still warms up slowly. Just in case you aren't aware, air cooled bikes shouldn't just sit idling for extended periods. Without air moving through them they can overheat.

You should be able to access the oil and neutral lights quite easily. The beauty ring around the ignition switch just unscrews and the cover will come off. If you have checked the bulbs and the sockets, you will have to work backwards though the wiring harness. I strongly suggest you get a factory service manual. These bikes are fantastic and you have a brilliant example. Good luck.

Thanks for this. Ive been searching through the forum, and it seems there is a switch somewhere near the engine that burns out from time to time. If anyone cares to chime in, please do

Neutral switch location



Shortcut the neutral switch connector to the engine housing or any bare metal part (neutral light should be come on).




Wiring Diagrams




Michael

Assuming the photo you posted is your bike it is not a 1977 KZ650. It is a 1978 KZ650. It could have been built toward the end of 1977, but just like cars bike models start being built a bit before the model year of the bike. Otherwise there would be no models available in January other than last year's models. There should be a label with the date and the VIN on the steering stem neck. If not, at least the VIN will be stamped there.

Your bike is either a 1978 KZ650-B2 or a 1978 KZ650-B2A. The B2A models used 22mm carbs rather than the normal 24mm carbs. To tell the difference you can probably hold a small mirror in the airbox to see the rear of the carbs. The image below show the extra orifice that the 22mm carbs have.

In any case, your bike is a real beauty! I sincerely hope you intend to keep it stock. Stock KZ650's are becoming extremely rare, and as far as I am concerned look far better than any modified ones. Ed

650ed wrote: Assuming the photo you posted is your bike it is not a 1977 KZ650. It is a 1978 KZ650. It could have been built toward the end of 1977, but just like cars bike models start being built a bit before the model year of the bike. Otherwise there would be no models available in January other than last year's models. There should be a label with the date and the VIN on the steering stem neck. If not, at least the VIN will be stamped there.

Your bike is either a 1978 KZ650-B2 or a 1978 KZ650-B2A. The B2A models used 22mm carbs rather than the normal 24mm carbs. To tell the difference you can probably hold a small mirror in the airbox to see the rear of the carbs. The image below show the extra orifice that the 22mm carbs have.

In any case, your bike is a real beauty! I sincerely hope you intend to keep it stock. Stock KZ650's are becoming extremely rare, and as far as I am concerned look far better than any modified ones. Ed

Thank for your advice. You are right. it was built towards the end of 1977 but is a 78!

And yes I plan to keep it stock. i would never ever hack up a bike like this into a cafe racer. No way.

thanks. All of the signal lights come on,its just they dont show up in the "tree" between the gauges.

The 2 links below contain information about your KZ that you should be aware of. If nothing else be sure to read the section about JIS vs Philips fasteners. Ed

www.kzrider.com/forum/10-new-members/607...san-francisco#772643

www.kzrider.com/forum/10-new-members/607...san-francisco#772644

Ive heard that these bikes are cold blooded. Mine takes forever to warm up. Is this normal?

650Dude wrote: Ive heard that these bikes are cold blooded. Mine takes forever to warm up. Is this normal?

Yes, that is a common complaint.
Perhaps you have a couple of burnt out indicator bulbs, but I think it more likely that there is a loose connector, probably in the headlight bucket.

650Dude wrote: Ive heard that these bikes are cold blooded. Mine takes forever to warm up. Is this normal?

Define "forever." When it's relatively cold outside mine may take 5 minutes or so to warm up. Keep in mind these bikes have carbs rather than fuel injection and have no computers to vary the fuel mixture to compensate for different temperatures. Ed

650ed wrote:

650Dude wrote: Ive heard that these bikes are cold blooded. Mine takes forever to warm up. Is this normal?

Define "forever." When it's relatively cold outside mine may take 5 minutes or so to warm up. Keep in mind these bikes have carbs rather than fuel injection and have no computers to vary the fuel mixture to compensate for different temperatures. Ed

Right. Ive had vintage bikes all my life, prefer them to new bikes and I pretty much know how they should, at least, work. This one takes a bit to warm up and even when warm, drops off when I took the choke off. I figured it out though. The idle was down too low. I adjusted it via the idle screw and everything is ok now.