Turn signal blink rate rises with engine RPM's

I put 2000 miles on my 1981 since getting it road worthy late last summer.  One thing I've noticed is that the turn signal blink rate is normal up to maybe 3500 or 4000 RPM, then the rate increases with the engine speed.  Living next to I90 in South Dakota, I routinely cruise 80 to 90 mph; 5000 RPM gets me 80 mph and by then, the blink rate is quite fast.  Is this normal, a sign of the generator over charging, or other problem?  She's only got about 6000 on the odo.

Thanks.

I suspect you have a regulator/rectifier issue and would check your battery voltage against engine speed - early type turn signal relays are sensitive to voltage and it's normal for the relay to flash slower at engine idle speeds where battery voltage is generally around 12.5-13 volts. However, above about 1500 rev/min the generator should be producing enough power for the regulator limit to apply which should stabilise at around 14.5-15 volts. The fact that your relay seems to flash even faster above 4000 rev/min suggests that the voltage is continuing to rise?

Adding to Neville's comments, also check the 3 phases coming from the stator windings to the regulator. You may have an open phase causing lower charging output at lower rpm's. LOTS of reports on the site with shorted stators and open phase stators. It's unfortunate that Kawasaki back in the day elected to go with Shunt regulators which operates the charging system at 100% output all the time instead of using MOSFET regulators which  modulates the charging system to the needs of the draw on the charging system. The MOSFET regulators run the stator at much cooler temperatures. There's a ton of information on this site regarding the upgrade to either a MOSFET regulator or a series regulator. And be leary of where you buy MOSFETs from. A lot of Chinese garage out there especially on EBay.

This is a good read  50 amp RM Stator

I can highly recommend the Shindengen SH775 regulator which has solved my perennial charging/stator overheating issues - It does just fit in place of the stock regulator with some minor mods to the mounting bracket - some other options are too big and need to be placed in the tool tray on the carb models - agree with Kawboy that there are a number of inferior copies on various selling sites - there are some very clear clues on what is genuine or not so worth doing your research first.

See  www.kz1300.com/index.php/forum/welcome-n...79-z1300-a1?start=18

Just to confuse things.... MOSFETs are not limited to 'series type' voltage regulators and are also used in some 'shunt type' voltage regulators and have some advantages over the thyristors (SCRs) traditionally used in the shunt type.

Bucko wrote:

Just to confuse things.... MOSFETs are not limited to 'series type' voltage regulators and are also used in some 'shunt type' voltage regulators and have some advantages over the thyristors (SCRs) traditionally used in the shunt type.
 

You are correct Bucko and thanks for raising the point.
The Shindegen  FA020AA is a MOSFET controlled Shunt regulator and is better than the Kawasaki stock regulator because the MOSFET's can handle the load switching better than the stock unit's transistors. It's a step up going to the MOSFET shunt regulators, BUT- an upgrade to a series regulator is the ultimate "fix" for the problem.
Shindegen offers the SH847 as a series regulator and if you wish to buy on from one of the few Shindegen dealers, go to Roadster Cycle .   He is an authorized dealer for Shindegen and helped us on this site to better understand our issue and how to fix it once and for all.

Also, as an alternative, RM Stator in Quebec Canada offers a series regulator @ $ 174.00 CDN and if I remember correctly, free shipping. This is a direct replacement for the SH847 offered by Shindegen. Both have a 50 amp capacity.  The RM Stator unit is also compatible with Lithium Ion Batteries just in case you also opt for a battery upgrade.  check out  RM Stator series Regulator