Just bringing the K75 back to life after being rained on for 2 weeks over Christmas....battery flat, so on charge....replaced some instrument cluster bulbs.
I have noticed that the main headlight is not functioning. the high beam position works off the right hand switch, as does the high beam flash switch on the left. I changed the headlight bulb, but there was no difference. Can anyone point me to the next port of call??
Thanks....and happy new year!!

A quite common problem at our K's, which most of the time is related to the LHS switch assy, which must be dismantled and cleaned/repaired if possible.

Have a look at this link.

Could also be the connector under the tank for this switch assy, but that isn't that much likely.

When you get it to function again, install headlight relays, to avoid this problem.

Could not agree with Inge more strongly about using relays because when you look at the switch innards the first thought is you cannot be serious, what useless swine designed this? Call those contacts I would only rate them for a torch bulb. Sadly that is not a problem unique to K's all bikes and cars are designed down to the lowest fraction of a cent. Using a relay set will make the lighting much more reliable, the easiest way is to use a relay kit from Jim at Eastern Beaver they are very reasonably priced and he does heavy duty waterproof relay kits with ceramic bulb connectors to allow higher wattage bulbs to be used. His kit is really simple to install and leaves the original wiring unchanged because the drive from the relay coils comes off the socket that was used for the bulb. A new heavy duty power cable runs from the relays to the battery via a fuse which is part of the kit he supplies. Installation is a no brainer and very quick, delivery is quick too. The web address is http://www.easternbeaver.com/Main/main.html
Regards,
K-BIKE

Tremendous info!! I'll have a bash at the switch tomorrow and see what occurs.
Thanks alot!

It would be a smart idea to disconnect the switch from the bike,
and dismantle/open it at the kitchen table......when SWMBO is out of the door.

Am I greasing the contact points on re-assembly? What is best to use?

Hiya BooG;

Here is another hint...as these bikes are really "mature" age now what is the chance the electrics have lasted this long and now have given up the ghost....check to see if you already have relays fitted and see if these have fuses...and if these fuses are ok.....personal experience talking here.

I decided not to in the end as I didn't want to risk attracting more dirt in there... What I did to was use Deoxit to assist with the cleaning and left a coating of it in place....

If you wanted to use a specific type grease to prevent water ingress and something like Maplins silicon dielectric grease would do the trick...

Maplin Grease

Thanks guys! I will do the same regarding the contacts and will explore the relay situation also. I am cleaning it all up on the kitchen table as we speak.

Just don't get the silicone grease on the contacts.
Regards,
K-BIKE

+1.

I have a rather alarming delay, i.e. no light at all for a second or two, when switching from dip to main beam, and I suspect that this topic may have already supplied an answer. I recall that my R75/6 had a headlight relay 35 years ago so why do the K bikes not use this obvious expedient?

Mr Grumpy,have you checked your switch contact.
mine lost contact, still gave me low beam, but no high.
good luck with it.

Been there, done that. Most likely from lack of use the light switch becomes hard to move and sticks in-between positions.
Consider removing the switch and putting a drop (one drop) of super oil on each of the switch hinges, then work the switch until it moves freely. Should work just fine thereafter. :bball: