Bike turn over very slowly (1979 xs1100)

[old_bartender]

1 check batter OK 12volt voltage drop to about 3 or 4 volt when starter is engage
2 turn moter with wrench on crank turn fine
3 pull starter clean and test out stater and rotor coil with vom test check out fine
4 bench test starter pull 15-25 amps
5 reinstall starter motor turn over slowly
6 remove wire from solenoid use small car batter to starter motor turn over slowly
7 put kick starter on use hand to turn over motor move fine
8 remove spark plug motor turn over fine with starter
9 put spark plug back in motor turn over slowly

do I have a bad starter (flying short) no torque under presser

[TopCatGr58]

You didn't mention CLEANING the starter casing to frame GROUND connections. The bolts that secure the starter provide the starter motor case/ground to the engine, along with the ground wire strap from there to the frame junction behind/below the carbs. Disconnect and clean, and then retest with the jumper car battery. IF the starter then turns over quickly, but still slowly with the bike battery points to the bike battery as being old/worn out and only holding a surface charge=12+volts, but no AMPERAGE reserve=slow turning!!

T.C.

[natemoen]

I am guessing bad battery.

[buffalo]

+1 on TopCat's advice... I had a 78 that would kick over easy but crank slow with the starter, especially hot. Ground cable from frame to rear of engine was the culprit. It looked fine on the surface but when the bolt was removed I could see it was hardly making connection. Check voltage drop from starter housing to battery neg terminal to verify.

[CRXSi90]

I am guessing bad battery.

That's what I thought when I read this:

1 check batter OK 12volt voltage drop to about 3 or 4 volt when starter is engage

but then I read this:

6 remove wire from solenoid use small car batter to starter motor turn over slowly

and if it's a known good battery, then I thought maybe not.

Where were you measuring the voltage when the starter was engaged? AT the battery terminals, or at some other convenient location?

[Geezer]

When using the small car battery to test the starter, where did you connect the ground, to the engine or to the frame. It's easy to forget that the engine in the XS11 is rubber mounted...

Tony