K75C from Kyushu to Tokyo

[gkanai]

Hello, new to the forum and new to BMWs.

I just picked up a K75C at auction for a very reasonable price. It apparently has less than 10,000 kms on the odometer, which is hard to believe. The previous owner said it ran about two years ago but it's no longer registered for the roads (in Japan.)

I'm going to rehabilitate it and put it back on the road, maybe with a new coat of paint. I have some mechanical ability, but I will also rely on a specialist vintage BMW mechanic in Tokyo (Flat BMW) who is near me. I have a ton of questions but will take time to go through the information on the forum. I'm very much open to ideas/advice.

One of my main concerns is about suspension. I'm a large rider and the OEM stuff is old, so I'm planning new springs up front, and a whole new rear shock. Any guidance on that area would be welcome.

Let me share photos in the next post.

[gkanai]

[AtLarge]

That’s a beaut!

[gkanai]

She needs some love but yes, I think she will turn out just fine. I had read about some bikes (and cars) in Japan being well-taken care of over the years and clearly this one was well-taken care of.

I'm looking for luggage. Does K1100LT luggage fit this bike? (Is all K-Bike luggage similar?)

[Laitch]

I'm looking for luggage. Does K1100LT luggage fit this bike?

Yes. The racks are the same for all models.

[gkanai]

Yes. The racks are the same for all models.

Great- thank you. I'll start looking for used luggage and mounting rails.

[natalena]

Welcome, and great looking brick. Is it a 1987?
Likewise, I have a K75, and have been happy with a YSS adjustable shock on the rear, and progressive springs in front with 10wt oil. We ride 2 up with luggage, so it works well for a load. Enjoy getting it back on the road!

[gkanai]

Welcome, and great looking brick. Is it a 1987?

Thanks! When I saw the mileage and the price, I had to grab it.

I do not know the year yet- the previous owner is still working to get it shipped to me.

Thanks for your thoughts on the YSS suspension. I'm looking at YSS but also IKON and the Progressive shock as well.

[gkanai]

I'm looking for tires for the K75C and am considering:

BATTLAX BT46 100/90-18 M/C 56V TL

ContiRoadAttack 3   100/90 R18 M/C 56V

DUNLOP ARROWMAX GT601 100/90-18 M/C 56H


REAR

BRIDGESTONE BATTLAX BT-46 TOURING 120/90-18M/C 65V T/L

ContiRoadAttack 3 CR   130/80 R18 M/C 66V TL C

ContiClassicAttack   120/90 R18 M/C 65V TL

DUNLOP ARROWMAX GT601 120/90-18 65V

[The Mighty Gryphon]

+1 on the YSS rear shock.  For the price, it is a very good deal.  I am very happy with mine. 

For the front end, I would suggest investigating Race Tech cartridge emulators and single rate springs. 

I put them in my K75RT and the improvement in handling and ride was noticeable.  Brake dive was greatly reduced while smoothing out the ride harshness over rough pavement.  I run Automatic Transmission Fluid(ATF) in my forks.

[gkanai]

+1 on the YSS rear shock.  For the price, it is a very good deal.  I am very happy with mine. 

For the front end, I would suggest investigating Race Tech cartridge emulators and single rate springs. 

Thank you! Did you get the YSS with the external reservoir or not?

I've run Race Tech springs Gold Valves before- I'll do the same this time.

[The Mighty Gryphon]

No, I didn't get the model with the external reservoir.  It's nice not having the reservoir or the line.  I replaced a Works Performance shock and the YSS in my opinion is as good or better than the Works shock.

[gkanai]

My bike has the Y-spoke 18" wheels. Is there anyone who has changed to the 17" Y-spoke wheels? I know that will throw off the speedometer probably (and the odometer?) but there's a lot more choice for 17" tires.

[volador]

All 1991-92 and newer model K75 have the 'Tri-spoke' wheels.

On your moto, do to the 'rear drum brake' your upgrade would require newer type final drive and rear disc brake assembly.

If you do upgrade need to make sure the newer Rear 'Tri-spoke' rim is of the 'TYP B'

K75 Rear Tri-spoke rim markings should read 36.31-2 310 188 MTH2  3.00x17E  TYP 'B'  which is not the rim part# but must be a manufacture# or such

I read rear Tri-spoke rims of the 'TYP A' and 'TYP B' have different off-set. I never measured to verify.

Probably because of paralever vs. monolever final drives rear wheel rim installs.

[gkanai]

@volador, thank you. That's a lot to think about. I may stick with the 18" wheels and see how that goes.

[volador]

@volador, thank you. That's a lot to think about. I may stick with the 18" wheels and see how that goes.

I agree, tough finding the parts. Use what you got, its very nice looking moto, good tire choices.
 
If that is the correct kilometers you are lucky dude.

Apply 303 Aerospace Protectant, Meguiars M40, or ArmorAll to revive all the plastic, vinyl parts

Check condition of the inside of fuel tank. Lowest portions are prone to corrosion when moto is left sitting for some time.

Rubber fuel pump damper will disintegrate over time left sitting in petrol.




Some links for your K journey Good Luck

Just bought a 2V

Just bought a 4V

K75s midlife refresh

Check parts compatibility with BMW MAX Microfiche, BOBS BMW, REAL OEM

https://shop.maxbmw.com/fiche/PartsFiche.aspx

https://shop.maxbmw.com/fiche/PartsSearch.aspx

https://parts.maxbmw.com/BMW___BmwMotorradK.html

https://www.bobsbmw.com/store/microfiche/BrowseSeries.aspx

https://www.realoem.com/bmw/select.do?kind=M&arch=1

https://www.ascycles.com/BMW-Motorcycle-Parts-Fiche

Cross reference parts like Bosch pn#'s, etc....  http://partsplusecat.com/
No spaces in the part number

Parts Vendors

https://www.beemerboneyard.com/

https://www.capitalcycle.com/

https://www.euromotoelectrics.com/

https://www.tills.de/

Headlight relay stuff if you chose to add one

https://www.motobrick.com/index.php?topic=268.0

http://www.motobrick.com/index.php/topic,4962.msg30932.html

http://culayer.com/product/matchbox-headlight-relay/

http://easternbeaver.com/Main/Wiring_Kits/H4_Kits/h4_kits.html  Eastern Beaver site is a great reference for electrical connectors,plugs, etc...

http://www.k100-forum.com/

http://www.kforum-tech.com/Tech-page.html

http://www.kforum-tech.com/electrical/EFI/bike-wont-start-EN.htm

http://www.kforum-tech.com/Downloads/electrical/diagrams/interactive_diagrams.htm

http://www.kbikeparts.com/classickbikes.com/ckb.tech/0.ckb.tech.files/k100tshoot/K100.Troubleshoot.Start.2018.pdf

http://kbikeparts.com/index.htm

http://www.kbikeparts.com/classickbikes.com/ckb.tech/ckb.new2k.htm

http://www.kbikeparts.com/classickbikes.com/ckb.tech/ckb.tech.toc.htm

http://www.eilenberger.net/K75S/IgnitionSwitch/

http://www.verrill.com/moto/moto.shtml

this site has a lot of good info and breakdown pictures in the tech and tech resources sections for K1100 alot of the parts are on K75 & K100

http://www.k11og.org/forum/index.php?sid=2df953dde5715fd9001fbe69edec5ad0

https://ibmwr.org/index.php/k-bike-tech-articles/

This site has all kinds of technical specifications on all the BMW models    http://www.bmbikes.co.uk/mechanicalpages/kseriesmechanical.htm

http://largiader.com

http://bmwk10075abs1fix.web.fc2.com/index.html  Toshi ABS site

Hosa D5S-6 CAIG DeoxIT 5% Spray Contact Cleaner, 5 oz.

CAIG Laboratories D100L-25C Contact Cleaner Needle Dispenser

Oil/Water Pump

pre-1986-87? original design old style impeller 11411461177

Superseded by 11412325850 design change the shaft with gear Z=32 teeth, shaft- 11411461183

Superseded by 11417676366 same shaft with gear Z=32 teeth

latest design 11517676371 design change shaft with gear Z=19 teeth, shaft- 11411461793

3-Bond 1184 Service Bulletin

Slip-ring seal for water pump Service Bulletin

Oil Water Pump Seals K-models SB 11 039 89 2352

https://www.euromotoelectrics.com/product-p/pumpkit870.htm

https://www.euromotoelectrics.com/product-p/pumpkittool628.htm

[gkanai]

@volador - thank you for the great list of resources!

I now know my bike is a 1986 model.

The YSS dealer in my country says that the spring that they normally sell on the shock for the K75 is ID46 45-60N/mm L-220mm.

That spring is way too weak for my weight. YSS thinks that I would need a 100 N/mm spring but that the largest they have is 80N/mm.

I may have to look beyond YSS.

[gkanai]

Welcome, and great looking brick. Is it a 1987?
Likewise, I have a K75, and have been happy with a YSS adjustable shock on the rear, and progressive springs in front with 10wt oil. We ride 2 up with luggage, so it works well for a load. Enjoy getting it back on the road!

It's a 1986, I now know.

Regarding your YSS shock, did you replace the OE spring with a heavier spring to account for your passenger? Do you know the spring rate of the spring? Thank you in advance.

[gkanai]

Ok so the bike has arrived. Exciting! It's a little rougher than expected since the auction photos were not that close up, but I know it's not really running at the moment. I'm sharing a few photos now, will take more later. Clearly that injector rail needs to either be replaced or re-finished, and the injectors probably need a cleaning or replacement. If there is anything that jumps out at anyone, please let me know.

[stokester]

Looks like a good project. I like the YSS shock and have one on each of my K75Ss and Race Tech fork springs in the '93.  My current favorite tires are Metzeler Roadtech 01 although I do like the Avons as well.  I'm currently rebuilding the forks on my '78 R100S using HyperPro springs and if I like them will probably consider a set for one of the bricks.
I don't see any oil in the sight glass! 

[Laitch]

It is certainly photogenic but slightly disappointing in person. I'm like that, too.

Apply heat and then Liquid Wrench or its equivalent to all stubborn, rusted fasteners; otherwise, it should clean up fairly easily with a case of Scotchbrite pads and rattle-can paint to become the glorious icon of moto transport it was meant to be.    Although the parts fiches show that seat strap, the one on yours is the first one I've seen in a member's photo. 

[gkanai]

I don't see any oil in the sight glass! 

Thank you for the feedback on tires. Metzeler doesn't sell any tires that fit the K75 in Japan apparently.

The bike only has the side stand, so that's why there's no oil in the sight glass. I'm going to look for a used centerstand and the parts to make that work.

[gkanai]

It is certainly photogenic but slightly disappointing in person. I'm like that, too.

LOL! Yeah, me too. Thank you for the advice on the Scotchbrite- will buy a box and will look for a gas heat source

[The Mighty Gryphon]

The engine corrosion can be cleaned up with an aluminum cleaner.  Aluminum Jelly is a product that can be used.  I also use aluminum brightener that I get at the auto parts store. 

Follow the cleaning with a self etching primer and then your paint.  I find that a semi-gloss engine enamel works well.

[gkanai]

The engine corrosion can be cleaned up with an aluminum cleaner.  Aluminum Jelly is a product that can be used.  I also use aluminum brightener that I get at the auto parts store. 

Follow the cleaning with a self etching primer and then your paint.  I find that a semi-gloss engine enamel works well.

Thank you! I'll look for similar products here in Japan.

Regarding finding a used centerstand- are all of the K-bike centerstands the same? Can I get a used K100 centerstand and use that on my K75?