New K75RT Owner in PA

[jdub]

Greetings all from a long-time BMW owner (mostly Boxers, sorry) with a newly acquired 78k mile, one owner 1995 K75RT. I owned/rode a 1990 K75S for 72k miles, so that'll help ease my transition back into brickland. I was glad to find this site as it appears to be a great resource for all things K.

I bought the new-to-me RT mostly with the intent of mostly using it as my commuter (116 mile roundtrip, beginning in the morning darkness at 0400), but maybe not during the summer months as I still remember how hot my K75S was while living and commuting in TX (inner thigh burns on one memorable 108 F. day). Picked this RT up for a very attractive price, knowing that I was going to first completely go through it to inspect and lube the FD and clutch splines, change all fluids and filters, check/adjust valve clearances, install new tires, and deal with anything else that came along. With my aircraft maintenance career/background I enjoy wrenching on my bikes almost as much as riding them, and I couldn't wait for the deep dive into this one.

Issues I've found so far are wear on the driveshaft rear splines/FD splines, a rear main seal leak, malfunctioning gear position indicator, bent sidestand, a pulsing front brake rotor and one heated grip malfunctioning. I'll replace the seal as soon as my parts order arrives, the other items will be dealt with during reassembly. After reading a lot about K-bike FD spline wear, I'll likely just ride it as-is and then wait until summer to address that.  All of the clutch components are in great shape, as is the rest of the bike.

I guess ignorance is bliss, because the entire time I owned the S I never knew that FD spline wear was a thing on these bikes and its driveline had never been disturbed. I sold it outright to a BMW dealer in 1997 for use as his personal bike, and he never asked me about any spline lube history.

Looking to glean lots of intel from the collective knowledge of this site, and to participate when I can. And I'm a firm believer in searching before posting new questions.   

 

[jdub]

Well, that was an interesting result once I actually clicked the Post button. If I can find an Edit button (is there one?), I'll attempt to clean that up.

[The Mighty Gryphon]

Welcome!  Looks like you got a nice one! 

"Modify" = "Edit"

Photos taken with iPhones seem to have orientation issues.  I always take my photos with a real camera to avoid orientation problems.  You will be getting a snarky post to this thread from Laitch about posting photos.  Don't be offended, it's just the way he is.

[jdub]

Thanks for the welcome and for cleaning up my original post. Continuing my education.....can you please advise where the "Modify" button or option is on the screen? Probably right in front of me, but I absolutely cannot find or see it anywhere.  Thanks.

[bocutter Ed]

Thanks for the welcome and for cleaning up my original post. Continuing my education.....can you please advise where the "Modify" button or option is on the screen? Probably right in front of me, but I absolutely cannot find or see it anywhere.  Thanks.

You need a 10 post count before you're allowed to edit ...

[jdub]

You need a 10 post count before you're allowed to edit ...

Ah, thanks! Good to know my eyes weren't so bad after all.

[natalena]

Welcome, and great looking RT. There's several brickster's in the central PA region, they may chime in.

[Martin]

Welcome to the asylum. A lot of the tank heat issues can now be reduced. I did a three day 1400 Km jaunt on a black K75s in 40 C temperatures with no heat issues. Actually saw 49 C on the dash thermometer  which dropped to 41 C once moving again. TMG and others  have fitted a fuel cooler and I fitted a fuel rail heat shield both methods have significantly reduced the heat from the tank. I also insulated all the external fuel lines with foam pipe insulation, and fitted double sided reflective insulated foam sheeting under the tank and behind the side covers. Hydration and appropriate vented riding gear is a must.
Regards Martin.

[jdub]

Thanks for the welcomes.

I've read about adding insulating panels to the bottom of the fuel tank, and will be doing so when I remove the RT's tank in the next week or so as part of my general inspection of the bike's condition and to route the new clutch cable I bought for it. I can't remember how heavy the clutch pull was on my old K75S, but currently on the RT the pull is very heavy - much more so than either my GS or DR. Especially because I fight a continual on/off battle with tendonitis in my left forearm, a heavy clutch pull is one of my worst enemies. I know better than lube any BMW cables due to their inner lining, so I'm just going to start fresh with a new one.

I've also been looking the sidestand retract mechanism tied to the clutch release, and can't recall if my S had the same set-up. I have to think that adds a bit more resistance at the clutch lever, and unless someone tells me that the bike will immediately go up in flames or the Motronic will permanently seize up if I do so, I plan on disabling that 'feature' during my reassembly. I realize it's meant to be a safety item, but lack of it will just make this bike like every other one I own now or have previously. Any slick methods for further lightening the clutch pull on these bikes, other than the basic lubrication of the cable ends, etc., would be most welcome.

I also noted loose steering head bearings during my single ride so far on the bike, but it doesn't feel as if the races are dented so adding the proper bit of preload should be an easy task.

Cheers

   

[Laitch]

I can't remember how heavy the clutch pull was on my old K75S, but currently on the RT the pull is very heavy -
I've also been looking the sidestand retract mechanism tied to the clutch release ...

the Motronic will permanently seize up

There are a few friction points in the clutch setup: the clutch arm at the transmission, the nipple attachment at the clutch hand lever and the clutch cable routing. The nipple and clutch arm need regular lubrication but if the cable is routed incorrectly, it can take main force to squeeze the hand lever. Three relatively healthy and mobile fingers should be able to pull the hand lever adequately. The side stand retraction feature can be set up so little extra effort activates it; after the stand is retracted, the retraction mechanism should have no discernible effect on lever pull.

The K75 has a Jetronic fuel injection control unit. The Motronic unit is used on the space-age 1990–1992 K100RS and the K1100 16 valve models. The 8 valve models are in the Red Flyer category of Bricks. :-) As a point of clarification, six- or eight-valve models are also termed 2V; 16 valve models are also known as 4V.

[The Mighty Gryphon]

As per Laitch, the sidestand mechanism does not affect clutch operation when the stand is retracted. 

On my K75, even though it can push the stand up, it only acts as a reminder that the stand is down.  I feel the increased resistance and kick the stand up with my foot.  All in all, it's a good safety feature.

[Martin]

Although BMW advises not to lubricate the cables it can be done using the correct lubricant. Because the cables are Teflon lined you need to use a PTFE lubricant like Tri Flo, the cables will benefit. Do not use non PTFE lubricants. You will be surprised at the crap that is flushed out when you do this.A grease nipple can be added to the clutch arm and will also help.
Regards Martin.

Clutch grease nipple 2.jpg (38.33 kB . 768x576 - viewed 622 times)

[caveman]

Nice truck!
So that KDX isn't yours (not in sig line)?
As far as cable routing some say that routeing through the left side of triple tree made for easier pull but all 5 of mine are through the right side.
Good luck with the "new k75rt" neighbor, it appears to be in good hands.

[jdub]

Thanks for the comments regarding lube of the various clutch mechanism pivot points, certainly plenty of them on this bike. Since the sidestand retract mechanism is so simple to remove and install, I'll likely try it both ways and then decide my preference.

Thanks too for correcting my faux pas on Jetronic vs Motronic. Showing my long-time Boxer roots there as Motronic was on three of those I've owned.

Nice truck!
So that KDX isn't yours (not in sig line)?
As far as cable routing some say that routeing through the left side of triple tree made for easier pull but all 5 of mine are through the right side.
Good luck with the "new k75rt" neighbor, it appears to be in good hands.

Thanks, I bought that Tundra a year ago as an early retirement present for myself, figuring it made more sense to make payments while still having income. Carried the GS in it to San Antonio in April while my wife and I visited my son and his family and we hauled lots of household items down for them. Rode the bike from there out to Big Bend National Park for a few days, nearly got stuck off-road in some deep sand only once.   


20190408_122151.jpg (90.08 kB . 768x432 - viewed 568 times)

The pics in my original post ended up a bit jumbled, and that photo of my KDX200 and K75S was from 1995 before moving from Texas back to PA. Both were sold a few years later and have since been replaced by a string of other bikes.

Thanks for the reminder on routing of the new clutch cable. It's possible that's the original cable now on the bike, with no guarantee that it's routed in the best manner.     

[alabrew]

I too have considered disabling the safety features for the side stand for both k100's, but question, "is this safe?"
I hate that the RS lets me crank and crank and nearly start when the stand is deployed.
The auto retract on the standard is just a sometime annoyance as I tend to want to keep the clutch pulled in and deploy the stand.
I rarely leave any bike on the side stand, it is just to git off and put it on the center.

[jdub]

My driveway has a very slight downward slope from my garage to the street. My routine with all of my bikes is and has been to push them out of the garage while in neutral, put the sidestand down,  pull the clutch in, start the bike and let it idle while I go back and hit the button to close the garage door. Centerstand use here is likely to result in the bike rolling forward off of it.

My normal routine's not possible with the sidestand retract mechanism on this K, and since the first thing I always do after swinging a leg over a bike is to retract the sidestand (have to on the GS, as an interlock will kill the engine if placed in gear with the sidestand down). This one seems a bit unnecessary and intrusive to me. Different strokes and all that, YMMV, etc.

[Past-my-Prime]

Once it's running and in neutral, you can put the sidestand back down (with the clutch out). I don't know how many people have driven off with the stand down but it would not be a pretty picture. I don't use the clutch to retract the stand; if I hit the resistance I manually flip it up with my left foot. It is probably a useful reminder.

[Laitch]

My routine with all of my bikes is and has been to push them out of the garage while in neutral, put the sidestand down,  pull the clutch in, start the bike and let it idle while I go back and hit the button to close the garage door. Centerstand use here is likely to result in the bike rolling forward off of it.

My normal routine's not possible with the sidestand retract mechanism on this K,

Sure it is unless you've somehow fouled up the adjustment or the Neutral indicator is faulty. The side stand retractor has nothing to do with starting. Once you push the moto out of the garage, lean it onto the side stand. If the transmission is in Neutral and the Neutral indicator is functioning, you should be able to start it. The thing is, it's best to start this moto's engine then ride off, not let it idle.

The side stand retractor's function is to keep you from spilling yourself into the hospital after your first left turn while you were distracted by ruminations concerning mechanical function and failed to lift the stand. Different strokes, I know. Some people like the attention given by emergency room staff.  :-)

[stokester]

Welcome!
In addition to the clutch lubrication points brought up by Laitch be sure to clean and lube the barrel at the end of the cable in the lever.  It will eventually start to bind and cause the cable to flex and eventually break.  I've replaced a couple while on the road and always carry a spare with the barrel.

[Martin]

You can significantly extend the life of your cables with correct maintenance. I've only just replaced my first throttle cable and still running my original clutch cable. Worn levers contribute significantly to broken clutch cables.
Regards Martin.