Idle problem

[mike10]

Hi, I rode my 1980 GS1000 to work ,about 20 miles ran fine. When I stopped to park, it started to Idle slower and slower then quit running. I tried to restart and it cranked very slow. So I quit trying to start it and went inside. 8 hours later came out it started right up rode home ran fine. While waiting for the garage door to open it began to idle slower and slower till it died. So only happens when it is nice and hot. Then cranks like the battery is very low. Multimeter shows 12volts in the battery. Didn't find any air leaks. CVcarbs. Just put gas in that day. Looking for ideas what to do next. Thanks, Mike

[1_v8_merc]

Is it 12.0 even?
What is the voltage with the bike running at Idle?

What do your spark plugs look like?

[Steve]

Multimeter shows 12volts in the battery.

Under what circumstances?

Even before you turn the key on, the voltage should be 12.6 to 12.9 volts.

At idle, it can be about anything, but over 12.5 would be nice.

At 2500 RPM or so, it should be at least 14.0 volts

At 4000 RPM and up, it should be over 14.0, maybe as high as 14.5 volts.

.

[mike10]

volts on batt term

I stuck the multimeter on just now 9PM PST. 12.51 just while it is cool sitting.With the key switched on headlight and taillight on 11.91 volt. When I first got home and it was hot but cranking slow I put the meter on it and it was 12.something with the key off. still more than just 12 volts I don't remember what. My first thought was it had been running off the battery. Not charging and the battery just went dead. reading taken right off battery terminals. I didn' check the charging system yet.

[tom203]

Seems like hot weather has tired out your battery-below 12 volts with ignition and headlight on (before cranking) is low, but maybe your charging system is lacking. Do the tests

[mike10]

Ok

I'll check it out. Thanks

[mike10]

Cam chain

I found that my cam chain tentioner nut, knarled wheel and spring came off. I also must have forgotten to put the jam nut on the locking screw. The parts were down in the hole where the starter motor sits I don't have the cover on it. Could too tight of cam chain cause the engine to die at low RPMs and start hard when the engine is hot ? I found the nut for the set screw in my tool box. So I took the carbs and everything off and fixed it. I hope there is no other damage.

[Big T]

I found that my cam chain tentioner nut, knarled wheel and spring came off. I also must have forgotten to put the jam nut on the locking screw. The parts were down in the hole where the starter motor sits I don't have the cover on it. Could too tight of cam chain cause the engine to die at low RPMs and start hard when the engine is hot ? I found the nut for the set screw in my tool box. So I took the carbs and everything off and fixed it. I hope there is no other damage.

No,it won't

[mike10]

All back together

I got it all back together now. After fixing the cam chain tentioner. Guess I'll test the charging system. Thanks Big T

[tom203]

I got it all back together now. After fixing the cam chain tentioner. Guess I'll test the charging system. Thanks Big T

You did remember to back off locking SCREW and tighten lock NUT after reinstalling tensioner?

[mike10]

You did remember to back off locking SCREW and tighten lock NUT after reinstalling tensioner?

Yes I did,but thank you for reminding me. I forget crap all the time.

[mike10]

Quik test charging

12.55V with the key off. 12.14V with the key on headlight and taillight on. Started it up 13.26, 2500RPM 13.45V, 5000RPM for about 30 seconds never went higher than 13.45V . Guess I will check out the wires and connections. Then the stator.

[Big T]

Did you run a ground wire from the RR to the negative battery post?

[mike10]

put new RR

Did you run a ground wire from the RR to the negative battery post?

Yes I did, my RR is new. A few months old.

[mike10]

Stator

I just tested the stator all is within normal limits. I almost cried. So now I still don't know why this thing drops RPMs untill it dies but only at running temp. Then cranks like the battery is low. It just started doing this last week.