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Starter weak?

idtwika

New member
some background.
A 1980 R100T that has been sitting for 15 years (outdoors?) Previous owner said it was ruining when he was put up. (97,000 miles)

I bench tested the starter, dissembled the unit and cleaned and re -assembled and retested the starter. All good.
I installed the starter, and using the battery from my Tacoma (with 12.6 volts) and all I get is a loud clicking noise coming from the solenoid. The motor will try to run over, perhaps a quarter turn and then resume clicking. I am thinking voltage drop with the old 6 gauge battery cable so I replace with a new 4 gauge positive and negative from Euro Motive. Install and the same thing. I tested the clutch switch, kill/start switch and the starter relay for operation and all check out.

I then bypassed the starter relay, and used a short to apply 12 volts to the ignition terminal on the solenoid and the motor now will turn over with NO clicking sound but It seems to turn slowly considering the same battery spins up the 6 cylinder on my truck with no effort. It appears that the starter relay is bad. What about the starter? Was I amiss in not cleaning the solenoid when I took the rest of the starter apart? Or is the starter bad. Brushed looked good. light sanding on commutator, I guess in retro, it could have been warn too much.

What am I missing?
Thanks for your help
 
Starter

The starter will appear to turn over slowly because it takes more power to turn over two big pistons that six small pistons.
 
It seems to turn slowly considering the same battery spins up the 6 cylinder on my truck with no effort.

Means your problem is on the R100 - nothing else!

Could be the starter or poor conductivity of the connections (+/ground).

Do you put the jumper cables right on the starter or the battery?

Some auto part stores can do a load test for a starter.

OTH, after so many miles the bike might deserve a new starter!

/Guenther
 
It sounds to me like the friction/drag in the engine is more than the starter can overcome. I think it is an engine issue (stored outside maybe for 15 years) more than a starter issue.
 
Motor locked up? 15 years is a long time. Pull the plugs, squirt some oil in the cylinders, put it in gear and turn it over with the rear wheel.
 
Motor locked up? 15 years is a long time. Pull the plugs, squirt some oil in the cylinders, put it in gear and turn it over with the rear wheel.

I will get it load tested.
I had squirted oil in the cylinders, I did assume the walls were a bit dry. And I did could spin over the motor with the plugs out and using the starter. I did pull the starter back apart and re-test commutator and opened and cleaned the solenoid.
And yes, problem could very well be a bad starter.
Thanks for everyone chiming in, it is appreciated
 
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