No crank but will easily bump start

[EdwarddRichtofen]

I own a k75s from 1991… I have no response from the ignition.. I have tried with the clutch in and in neutral.. nothing.. I get no Wirring from the fuel pump.. no wirr from starter.. no click from relay.. headlight does not dim.. replaced top fuse.. still nothing.. I can bump start but it’s not a fun way to get around town. I will clean the starter and ignition switch to get rid of those possibilities.. Any ideas would be appreciated.

[frankenduck]

Link to clean it:
https://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/ignition2vclean/ignition2vclean.htm

[natalena]

If you disassemble the ignition switch, the white subassembly is really easy to crack when prying it from the black tabs. Best to warm it up a bit so it's not cold-brittle..our garage is always freezing, unless I light the kerosene heater an hour before working. Good luck, Cheers

[EdwarddRichtofen]

is there anything besides the switch it could be? I forgot to add that I had been bump starting the bike to get around but now I’m sick of the issue .. I’ll try it out and I’ll be sure to be careful with the plastic.. my R1100R is in the cold workshop.. thankfully I brought my brick into the living room..

[Laitch]

Sounds like a challenge!

Maybe the cause is starter grounding problems. Try mounting the Brick, leaving the ignition Off, putting it in gear, back-pedaling it a few feet then popping the clutch. Do that three or four times then try starting it. If it starts, your Brick likely has a dirty starter commutator and maybe even bad brushes. You'll need to clean the commutator and perhaps replace the brushes it they're too worn. Here's a tutorial. Also, clean the electrical connections to the starter and the battery ground connection at the transmission.

[EdwarddRichtofen]

I’ll try it out.. should I hold the clutch in when back pedaling or no?

[Laitch]

I’ll try it out.. should I hold the clutch in when back pedaling or no?

That's the only way you can do it and let the clutch out when you're rolling. Be careful you don't drop it on yourself when it jerks as the clutch engages. Once, I dropped my Brick at a standstill when the call of a Pileated Woodpecker got my attention. 

[EdwarddRichtofen]

Rocked the bike back and forth. Still nothing. Not sure if I mentioned but my headlight does not dim when pressing the start button. Could it be my ignition button?

[frankenduck]

Start button rehab:
https://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/startkillrehab/startkillrehab.htm

[EdwarddRichtofen]

Thank you for the link. I will do that rehab along with this…

https://www.k100-forum.com/t2342-starter-motor-cleaning-tutorial

…and will report back… got the oil head in the living room right now so this project will have to wait till that one is done…

[sooprvylyn]

I know its probably not this easy but...is your battery nice and charged?  Should read over 13v w a multimeter if it is.  Bike wont even crank if your battery gets too low, but your headlight would still turn on.

If its low, you'll need to figure out if your alternator is charging your battery, or if you just have a bad battery.

[EdwarddRichtofen]

I’ll test the battery as well while I’m digging in the starter… good idea

[sooprvylyn]

If you find its like 12v or less, this could be the problem.  Over 12.1v and the bike usually tries to crank, but 12 or less and you may get nothing at all....and the lower the voltage the more likely you'll get nothing from the starter at all.


The start buttons do get dirty too.  They are pretty easy to clean.  When you take the switch assembly off the perch, and remove the screws on teh back to gain access to the switches, there will be a small circlip for the start button switch.  Remove it carefully and dont lose teh small spring inside.  You should be able to clean the contacts with rubbing alcohol and a q-tip.  I've seen them get totally caked with grime and prevent contact.  It's a 10 minute thing to check if that's the culprit.