K75s trub

[B777Fman]

Aloha gents,
I'm running out of patience on this one and am turning to the wisdom of the motobrick for some assistance. I've got a '93 K75s, which has been essentially  trouble free for the two years that I've had it. I have no knowledge of the previous owners maintenance practices.

Short version:
Was in normal cruise and engine quit, like the plug got pulled. Got it home and proceeded to t-shoot. Plenty of cranking but no joy. Good spark. Drained fuel tank, discovered baseball sized glob of water at bottom. Completely cleaned tank , replaced filter, fuel pump and sock with new units. Checked injector operation and cleaned. Replaced fuel with no ethanol gasoline. Engine would hit when starting fluid applied, but THEN the headlight started to flicker and then headlight quit, so then of course the starter wouldn't engage. I will attempt to investigate the headlight switch... Any other ideas? Thanks in advance.- JW

[johnny]

greetings b777fman...

welcome to motobrick.com...

i aints no wrench... i rides them till they wont move and trade them in on hardley ablesons... butts this is what i gotts to say...

when there is whack of any kind that may be electrical or fuel related the 1st thing i do is backspin starter maintenance...

1-backspin starter maintenance...
2-clean fuel tank electrical connector...
3-clean and tighten all + and - connections at the battery and where they terminate...
4-clean jetronic connector...
5-make sure spark plugs are tight and wires are tight at coils and plugs...
6-can hear fuel pump pressurize when pressing start button on the 750...
7-jiggle ignition key to see what happens...
8-keep it on a tender so the battery does not go low...

then move on from there...

when posting up about whack its best to have on center stand and report whats on and whats not with just ignition on... such as dash lights... low and high head lights... turn signals... tail light... brake light... horn... then what happens when starter button is pressed...

then move on from there...

j o

[Inge K.]

, but THEN the headlight started to flicker and then headlight quit, so then of course the starter wouldn't engage.

Typical symptom of worn starter brushes and/or dirty commutator.

Search the forum with the key words......LSR relay+worn starter brushes.

[B777Fman]

Most appreciated, will look into this before stripping out philips head screw in light switch-jw

[Motorhobo]

Was in normal cruise and engine quit, like the plug got pulled.............Engine would hit when starting fluid applied, but THEN the headlight started to flicker and then headlight quit, so then of course the starter wouldn't engage.

Engine quit with or without power to everything else? I've had engine quit due to bad ECU connection -- pull plug, spray with contact cleaner, plug back in, as JO said...that connection can be wonky.

As Inge said, starter brushes are overdue for replacement if they're still original...that should be part of standard 75k mi service IMO.

Doesn't sound to me like anything out of the ordinary k-bike quirks...you'll figure it out soon enough.

[B777Fman]

Thanks Hobo, Indeed there was full electrical power when engine quit. Oddly enough I tried J.O's suggestion of a back spin and then the headlight worked… briefly.  Subsequently pulled the starter off per Inge's post and cleaned it all up with air and then used and eraser and 3000 grit to ensure contact. I measured the brushes and although they are clearly worn (6.5mm & 9.5mm) I put it all back on bike and will take a look at the LSR. I will go ahead and get new brushes, however living on the island generally precludes a quick replacement.

[johnny]

the load shed relay can be swapped out with the horn relay for troubleshooting purposes...

j o

[B777Fman]

Whew! Ok gentlemen, thanks for all the useful input. She fired right up. I regret that I was somewhat unscientific about the process and unfortunately am unable to say exactly what cured it as I didn't attempt a restart after each possible solution. It seems that it was clearly the water in the fuel that caused the initial badness and that perhaps with the multiple start attempts it became an electrical/starter issue. I did swap the horn relay with the LSR but seemed to have the same effect. Good things happened when I got into the starter and cleaned all that up. I will be ordering a set of brushes as they are indeed due. The other lesson for me, since the bike sits 3 weeks out of 4, is to use the no-ethanol fuel as I'm sure that the ethanol's propensity to absorb water didn't help me any.
Again a Big Mahalo for all da help. :2thumbup:

jw

[TimTyler]

Your problem is clearly the result of mounting the muffler on the wrong side of the bike!  :neener:

[The Mighty Gryphon]

Your problem is clearly the result of mounting the muffler on the wrong side of the bike!  :neener:

Along with the rest of the engine...!!!

[Chaos]

It's the British RH drive model  :neener:

[B777Fman]

Fixed the pipe..
jw