k75 starting problem - help please

[89477]

I have a 1991 K75, just bought and am going through it to make into a solid bike. One week ago I began to replace brake fluid, then a rear master cylinder - bike sat without being started for this week. I finished brake work today - after 3 days of rain and bike under cover of a carport. Went to start the bike - nothing doing. Have headlight and turnsignals working. Have 12.3 volts at accessory outlet. No gear indicator or neutral light coming on at all - and these worked before the brake work and the rain. Couldn't see brake lights, saw taillight. No sound of a starter relay clicking. Of course, have a full tank of gas (so pulling tank is not my preferred option, but can do if needed). Fixed: watch out for pinched brake light wires at master cylinder - they take out the bike's ability to start because they apparantly take out the gear posiiton indicator circuit.

[Dennie]

sounds like mositure in some of the connectors, my k would blank out the gear position indicator in the rain, water was getting in the switch. try an electrical contact cleaner on the connectors-note be careful to use contact cleaner and NOT brake/carb cleaner:nono . make sure as the cleaner dries, the pins remain dry. make sure your batt does not have just a surface charge, i.e. it has the ability of a high amp output.- but I dont think its the batt. this is tedious work but must be done. if you pull the tank, be careful putting the fuel lines back on for a secure connection- its a high press system and spraying fuel on a hot engine under your fuel tank while driving= challenger kaboom. well not kaboom but big flames possibly. oh yea watch the paint with the cleaner overspray. the biggest problem with trouble shooting ( IMHO) is not creating more problems with assy/ dissassembly process. good luck. :wave

[SweetT]

I've had this problem with every fuel injected bike I've owned. The soloution has been something that deals with the battery. Either a loose connection (yes, the lights can still come on even if the battery cables are loose) or a weak battery that isn't fully charged. Just last week my K1200RS wouldn't start because the battery wasn't fully charged up even though my voltmeter showed that the battery had 12.4 volts. I took the battery out and charged it for a few hours. Now the battery has 13.2 volts and starts the bike easily. My hunch is that you've got a battery that is going bad. It can still hold 12 volts, but when you put a load on it, it doesn't have the oomph to turn the starter over.

[dswilliams47]

You say the neutral light and gear selection don't display. How about the other idiot lights (oil pressure, alternator)? If they aren't displaying either then you have an issue with the kill switch. Either it got bumped into the off position or perhaps moisture has shorted it out.

Dave

[will3hawks]

Saw your post and some of the good advice that you have been given. One of my own personal maintenence musts is Dielectric Grease. Spend some time hunting down any and all electric connections, wire brush any you can, clean with contact cleaner (not brake clean) and coat all the male and female connections with said grease. I have found that this makes a radical difference in an electrical connection's ability to function in less than ideal conditions. When you start pulling apart the connections you will find that there is the dreaded "white crud" which is oxidation and just a spot or two can cause guages to go wacky, bikes not to start, etc. One of the characteristics of of K bikes is that they tend to start when others will not, ergo if yours is not starting, the electrical system needs attention. The good news is that most of it is very simple and simply requires being sure that your connectors are in good shape. When you get your K75 sorted out you will find that it is as reliable as a rock. One last suggestion is to make sure to change the coolant every 2 years and use the BMW stuff as you will have less trouble with your cooling system.

Regards,

Will

[89477]

Hi and thanks to all who gave advice. I caused the problem when I replaced the rear master cylinder and inadvertantly pinched the rear brake switch wire during reassembly. This circuit also contains the gear indicator switch and neutral switch. Fixed the short, replaced the fuse, all is okay. Have been sorting her out now for several weeks now - dielectric grease at connectors has been done amongst other things, coolant changed too. I great ride! Dave