TOPIC:

Is there something wrong with the stock coils? Reason for asking is that the OEM coils are high quality and rarely fail. Many of the KZ coils have detachable wires too so it's easy to renew them if you want to do something.

Nessism, The coils are in perfect condition. I also have 2 spare coils. But people are saying the bike will perform and idle better. Any upgrade is good.

Running greys on one of my turbos work fine .

man-of-war wrote: Nessism, The coils are in perfect condition. I also have 2 spare coils. But people are saying the bike will perform and idle better. Any upgrade is good.

I disagree that those aftermarket coils are better than stock. Do as you must though.

Nessism wrote:

man-of-war wrote: Nessism, The coils are in perfect condition. I also have 2 spare coils. But people are saying the bike will perform and idle better. Any upgrade is good.

I disagree that those aftermarket coils are better than stock. Do as you must though.

Agree. I found the stock coils on my 1977 KZ650-C1 to be of excellent quality. I've owned the bike for 41 years and the original coils still perform like new. Ed

man-of-war wrote: Nessism, The coils are in perfect condition. I also have 2 spare coils. But people are saying the bike will perform and idle better. Any upgrade is good.

How can you improve on perfection?

I have "upgraded" stock coils to aftermarket Dynas and Accels. I didn't notice any change in performance. Obviously if a coil is defective (they can breakdown gradually) or a wire is bad, then new coils will seem like an improvement.

I've even swapped to cheapo Ebay coils. They worked equally good. So if coils and ignition are working properly, you won't notice much difference on a well tuned motor. Motors in poor condition or poorly designed will sometimes show performance differences with different coils and ignitions, but a good Kz shouldn't.

The factory coils were usually 2.3 ohm, so the 2.2 ohm, full-size, grey Dyna coils would be the closest match to a stock system. 3 ohm, full-size, green coils should also work fine, and would give the option of going to a Dyna S if needed in the future.

Rough idle check valve adjustment, make sure intake boots not leaking, syn throttle bodies, and if still rough but TPS Sensor up a smidge.

DFIGPZ wrote: Rough idle check valve adjustment, make sure intake boots not leaking, syn throttle bodies, and if still rough but TPS Sensor up a smidge.

How do I syn the throttle bodies,is there a special Vacuum tool ??? If so could you link me the site. As well as the TPS Sensor.
Ive been trying to put my hands on one with no luck. the engine was rebuilt 5 or 7 years ago . I have Pictures of me opening the TPS AND REPAIRING IT. Works like a charm now, I dont get that variable Idle speed any more. I'll try to find the pix and post it..

Where are you located? The non smog valve cover say European.

TPS sensor



Leerlaufwiderstand = Ohm @ idle
Vollgasstellung = Ohm @ full throttle
Pin 1 - 3 = Ohm @ every position between idle and full throttle



Air temp sensor



Engin temp sensor

You might need to send the injectors out for a flo check and clean . Just sent mine out to rc injectors in california and had them done up . They came back looking like new . It was only like 120 or something for all four . Will worth it . Charlie on the turbo site actually sent them for me but im sure you could send them yourself .

You need a carb sync tool. My carb sync clocks looking like this
and are not the cheap Chinese crap you can buy for money.
I bought them 25 years ago for 150 German Mark = 75 Euro
and now they were sale for up to 250 Euro



A quick guide to sync the carbs:
first sync #3 with #4, (#3 is the master, all other are the slaves)
then sync #1 with #2 ( independent with #3 and #4)
then sync the pairs (#1 + 2) with (#3 + 4)
do little 1/10 turns only, every little turn interact with the other carb vacuum.
repeat the steps until you get the minimum difference on all carbs.



Have fun

Michael