KOSO gauges slow tach

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savethe2strokes
Posts: 513
Joined: Tue Jan 24, 2006 6:35 pm
Location: Kansas City, MO

KOSO gauges slow tach

#1 Post by savethe2strokes » Thu Oct 26, 2017 10:38 am

Bike: 1985 Yamaha RZ350
Mods: KOSO RX-2 Gauges, KOSO EGT gauges, ZeelTronic Ignition and PVS controller

So I followed the gauge wiring to the T. Everything works great, but I believe the tach is a little slow to read especially when in the upper RPM range. I either have a slipping clutch or the gauges can't keep up when in the upper RPM range. I have the KOSO gauge hooked up to the RPM signal wire out of the ZeelTronic and not off the coil. Preferred wiring is to use a signal wire from the stock harness. Since the RZ is cable driven that isn't an option. I used the Zeel RPM Signal wire instead. It seems to read perfect except it seems a little slow in the upper RPM range. Has anyone else noticed this? I think I'm hitting the RPM rev limiter before the tach even registers that.

I'll try to post a video of this.
85 RZ350-Messed up wiring

tacky1
Posts: 950
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Re: KOSO gauges slow tach

#2 Post by tacky1 » Thu Oct 26, 2017 4:32 pm

Wire it to the coild and set the speed to double and you will have no probs, Thats how I wired mine..
1985 RZv500
1984 RZ500 Hybrid
1986 RG500 Walter Wolf
1986 RG500 Skoal Bandit
1984 RZ350
1984 RZ350 Hybrid
1981 RD350LC
1981 RD350LC Hybrid
2009 CR500AF Supermoto 250X
2007 CR500AF 250X
1988 YSR50 (2)
1984 GPZ750 Turbo
1989 VFR750R RC30

savethe2strokes
Posts: 513
Joined: Tue Jan 24, 2006 6:35 pm
Location: Kansas City, MO

Re: KOSO gauges slow tach

#3 Post by savethe2strokes » Sat Feb 17, 2018 7:15 pm

tacky1 wrote:Wire it to the coild and set the speed to double and you will have no probs, Thats how I wired mine..
So you put it on the positive wire for the coil?
85 RZ350-Messed up wiring

MK
Posts: 814
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Location: Wolfenbüttel, Germany
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Re: KOSO gauges slow tach

#4 Post by MK » Sun Feb 18, 2018 3:06 pm

The Koso tach has a damping which is the cause to be "slower" than that jerky 30 year old stuff you'll find on old TZs.
I doubt using the coil signal will help, as the Zeel (and stock Yamaha) tach signal basically is identical to the coil primary signal (just the hi/lo levels are inverted).
Trying a different setting in the Koso programming would do the same.
(I needed 2C, 2P and Hi)

If you have a suspicion that something is wrong with the rev limiter, then first check with the handheld if the Zeel sees the right rpm and you set the right limit.
Bye
Martin

savethe2strokes
Posts: 513
Joined: Tue Jan 24, 2006 6:35 pm
Location: Kansas City, MO

Re: KOSO gauges slow tach

#5 Post by savethe2strokes » Sun Feb 18, 2018 4:44 pm

The tach shows the right RPM, but it just reacts slowly. At idle the right RPM is shown but when I rev the bike it is goes up on the tach very slow.
85 RZ350-Messed up wiring

MK
Posts: 814
Joined: Sat Nov 26, 2005 11:44 am
Location: Wolfenbüttel, Germany
Contact:

Re: KOSO gauges slow tach

#6 Post by MK » Fri Apr 27, 2018 8:11 am

Some Zeels have two tach signals available.
Did you use the yellow /green cable?

Other than that: how about posting a video somewhere for us Koso owners to compare and rate if yours is ok?
Bye
Martin

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