Motorcycle Repair/cooling


have a 1986 1100 shadow, my first water cooled bike, replaced thermostat  , cooling switch in rad.. was stored in garage, 3, 4yrs before I acquired it) how hot should it get on the gauge before fan runs. Its seems to get more than half across, and still not run,  Idles higher then , I feel it should run then.
Am I correct in assuming that the fan should  keep a relatively constant temp, same as my truck ? Thanks, Frank

Hi Frank,

The gauges often read very high before the fan runs on these.
It may read over half and even up to the red before kicking on.

It will likely only run when stopped totally and go off when moving.

You can connect a battery to the fan to see if it is working.
There is a 10 amp fan fuse under the right side cover I believe.

Later models were changed to a light so riders wouldn't be
worrying about the high gauge readings and calling Honda.

If the fan runs at all it is probably okay, the gauge is not too accurate.
Just watch that you are not losing any coolant due to boil over.
Could have a bad rad cap.

It is normal for the fan to run rarely and only when stopped.

Wayne S.

Motorcycle Repair

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Wayne S.


Licensed Motorcycle Mechanic, Knowledge of motorcycles from 1960 up, Japanese, British and most other brand motorcycle repairs.


Worked for Yamaha, Honda, Suzuki, Kawasaki British: Triumph, Norton, BSA Other: Most Scooters and Mo-Peds

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