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1Back to top Go down    low speed cutting out. on Thu Jul 06, 2017 8:13 am

bigdavergs

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Hi all,a little bit of help neededplease. Low speed cylinderscutting out on my '85k100 (naked with an RS fairing). Checked the past topics, theculprit seemed to be the coil as the problemis theengine would only run on two cylinders and the tacho would stop working,then the two cylinders would fire up, as would the tacho. Checked the coils, they were the older, originaltype still. Bought somenewer type as the topic suggestedwith the orange bits on them, fitted them yesterday, cutting out problem persists. My commute to work is about 5 minutes of town speed,20 minutes at100kph speed, so the twin cylinder problem is not a problem for long and once at speed, the bike runs well. Other work to the bike includes, new plugs, ignition switch taken apart and cleaned (looked brand new still) andEME plug leads were fitted last year. This problem has only started about three weeks ago.
Any other suggestions to sortout the problemwould be most appreciated. Many thanks, Dave.

    

2Back to top Go down    Re: low speed cutting out. on Thu Jul 06, 2017 11:51 pm

Holister

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A bit confused. Is it running ok then cuts out or is just not starting nor running on 2.
"Cutting out" implies its going ok then stops.

Try these

  • Check your spade connectors on the bottom of the coils particularly the earth connections.
  • Make sure the ICU plug is clean and properly seated. This is a common problem.
  • Make sure the HES connector plug front/right under the tank is clean and properly seated.
  • One of your HES may be Kaput.


__________________________________________________
1988 K100RT VIN No. 0094680
1989 K100RT VIN No. 0097367 (naked)
1996 K1100RS VIN No. 0451808
Fuel: 95 Octane
Engine Oil:Nulon Full Synthetic 15W50
Gear Box Oil: Nulon Synthetic 75W90
    

3Back to top Go down    Re: low speed cutting out. on Fri Jul 07, 2017 4:36 am

bigdavergs

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Hi Holister, thanks for the reply. I'll try to be a little clearer. Bike starts and idles fine, as soon as I pull away it intermittentlyruns on two cylinders and the tacho stops working. Once out onto the open road, it's fine. When I get to the town where I work, it will often drop two cylinders and the tacho stops working again. As mentioned, I replaced the original coils a couple of days ago with a pair of the orange tower coils to try and fix the problem, but theproblem persists. So, theissue happens hot or cold. Any more thoughts from anyone? Cheers, Dave.

    

4Back to top Go down    Re: low speed cutting out. on Fri Jul 07, 2017 4:45 am

92KK 84WW Olaf

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Have you any way of determining which two cylinders are causing the trouble? The tacho signal comes from oneof the coils and both coils get their signal starting from the Hall Effect Sensor.

If one of the sensors is acting up it will interfere with the signal for either 1&4 or 2&3 and will affect two rather than one cylinder.

I cant remember if its 2/3 coil has the tacho signal but its pointing to one of the sensors or to damage to the wire from the HES to the ICU.

Check and clean plug and pins on ICU. Can you swap the HES with another?

Still points to Holister's post.


__________________________________________________
1992 K100LT 0193214 101,000 miles
1984 K100RT 0022575 Baja Red bought 36,000 now 87,100 miles
1997 K1100LT 58,000 miles
    

5Back to top Go down    Re: low speed cutting out. on Fri Jul 07, 2017 6:49 am

duck

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FYI: There's two black/blue wires from the 1&4 coil. One goes to the tach and the other comes from the ICU.

If the tach goes out when you're running on 2 cylinders then I'd guess it's the 1&4 coil not firing.

One of the following may be the culprit:
1 - ICU going bad or connector loose
2 - One of the HES sensors or its wiring going bad.

The HES wiring is zip-tied to the right frame member that goes to the engine. You can try wiggling that to see if the HES wiring might be the issue.


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

6Back to top Go down    Re: low speed cutting out. on Fri Jul 07, 2017 8:33 am

RicK G

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If your 2-3 goes out the engine stops because the ECU gets it's signal to fire the injectors from that so the 1-4 coil/HES is where I would be looking for starters.


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If everything seems under control then you aint goin fast enough:- Mario Andretti
Bikes 1986 K100RT, 1993 K1100 LT, 1994 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 & 1976 SR 500 Yamaha for now
    

7Back to top Go down    Re: low speed cutting out. on Fri Jul 07, 2017 9:58 am

bigdavergs

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Many thanks Olaf, Rick and Duck for the excellent info'. Gives me something to work with and I've got plenty of spares, so we'll see how we go. Thanks again, Dave.

    

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