The engine only runs at idle and low rpm

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dirk
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The engine only runs at idle and low rpm

Post by dirk » Thu Apr 01, 2021 10:26 pm

Good evening everyone. :-)

I haven't been in the forum for a long time.
i hope you are doing well so far.

Unfortunately I still can't write in English. :oops:
so google helps ..


I was on the Autobahn today.
Engine ran more or less normally (felt a little sluggish).
suddenly loss of power when accelerating.
Temperature was normal.
but I could only drive at walking pace.
with every attempt to turn over approx. 4000 rpm the engine power is
collapsed.

Changed the spark plugs.
Spark plugs were wet and black.

No improvement with new spark plugs.
the engine starts up normally.
no suspicious noises
same game again when trying to accelerate.
The ADAC had to come.

What could have happened?

greetings
Dirk
KR-1S 1990
RG500 1987
RGV 250 1992
TZR250 (2MA) 1987

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JanBros
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Re: The engine only runs at idle and low rpm

Post by JanBros » Sat Apr 03, 2021 10:58 am

does it run normal under 4000 ?
My ultimate goal is to die young as late as possible !

Coose
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Re: The engine only runs at idle and low rpm

Post by Coose » Sun Apr 04, 2021 9:55 am

I assume it was previously ok, but have you fiddled with anything as that's the first place to look?
I would then check the resistance of the high and low speed stator coils, then have a look in the carbs to make sure nothing is amiss.

dirk
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Re: The engine only runs at idle and low rpm

Post by dirk » Mon Apr 05, 2021 5:56 pm

Hi Jan

Starting is normal.
then up to 4000 with very little power.

@coose

Thanks for the note.
i'll check the alternator.
I had only replaced the connector for the battery beforehand.

Statistically, it was high time something happened.
that went well for too long.
however
i still like the bike a lot.
i also have an RGV.
i prefer the engine from the KR1s.
KR-1S 1990
RG500 1987
RGV 250 1992
TZR250 (2MA) 1987

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JanBros
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Re: The engine only runs at idle and low rpm

Post by JanBros » Mon Apr 05, 2021 11:14 pm

does it run on 2 cylinders ?
checking resistance of stator might say it's ok, but that doesn't mean it is. incomprehensible weird shit like this is often a failing stator (the 3 seperate windings for the ignition).
My ultimate goal is to die young as late as possible !

dirk
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Posts: 342
Joined: Mon Jul 30, 2007 8:18 pm
Location: Germany

Re: The engine only runs at idle and low rpm

Post by dirk » Sun Apr 18, 2021 10:14 pm

Thanks for the support.

the resistors of the alternator were OK.


the resting voltage of the battery before another test drive was about 13V.
after that, only 3V :shock:

it was the charge regulator.
the charging voltage was over 16 volts at 4000 rpm.
that killed the battery.

interestingly, the engine ran completely smoothly at idle.
KR-1S 1990
RG500 1987
RGV 250 1992
TZR250 (2MA) 1987

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JanBros
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Re: The engine only runs at idle and low rpm

Post by JanBros » Mon Apr 19, 2021 10:09 pm

you are lucky your tacho and CDI didn't fry !
My ultimate goal is to die young as late as possible !

dirk
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Posts: 342
Joined: Mon Jul 30, 2007 8:18 pm
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Re: The engine only runs at idle and low rpm

Post by dirk » Tue Apr 20, 2021 9:29 am

stupid question
If the CDi is grilled, does the engine no longer start?

i have now ordered a Tourmax charge controller.
i hope it lasts.
KR-1S 1990
RG500 1987
RGV 250 1992
TZR250 (2MA) 1987

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