MOTOBRICK.COM

MOTOBRICK.COM => Welcome To Motobrick.Com => Topic started by: Krautpleaser on January 27, 2021, 08:38:00 PM

Title: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: Krautpleaser on January 27, 2021, 08:38:00 PM
Hi there. Doing a test ride on a 85 K100rs on Friday. It's not cheap, but it looks extremely well kept. Yeah I know... who knows. Always a gamble. But I'm feeling lucky and will probably get it if the ride feels good.

Question: Guy said: "Everything works, including the ABS." Cool, but... that didn't come until later. Is it possible that someone retrofitted the bike with ABS?? Seller's story is that the bike is from a Dealer's collection, someone who sold these new back in the day. Again, who knows. Just wanted some more thoughts from you smart people.

Plus, any other tips on what to watch out for. Bike needs a new rear tire, and I'll definitely do the rear spline lube job while changing the tire. What else?

Thanks!
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: johnny on January 27, 2021, 10:01:13 PM
greetings...

sounds sketch...

photos and vin please..

j o
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: rbm on January 27, 2021, 10:05:55 PM
retro fitting an '85 with ABS is no small feat.  New harness, all the ABS components, replacement relay box, replacement cluster, etc.  Just a ton of work for what benefit.  Like Johnny says "sketchy"  Approach with extreme caution.
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: Past-my-Prime on January 27, 2021, 10:14:09 PM
Good quality, well-maintained bikes come up for sale all the time. A small sampling is on

 https://www.motobrick.com/index.php/board,35.0.html

and then there's

https://www.motobrick.com/index.php/board,117.0.html

Where some nice examples can be found.

Not that you might not be lucky -- good luck to you! (I was lucky but mine was only seven yrs old when I bought her, your will be over 35! 

If the guy is asking a lot, it won't go quickly.

Just my advice, best of luck.
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: blackie1 on January 27, 2021, 10:36:58 PM
in my opinion, the outer appearance will give you an initial indication if it has been looked after.
the ABS addition is .... unusual.
look for the basics. oil leaks, water leaks. make sure everything is dry around your brake lines.
then, if tires and brakes look like they will handle it, i would take it for a test ride and ride it as hard as i can. thrash it.
just up and down the gears in a straight line. don't go canyon riding on a bike you are unfamiliar with and don't yet own. you don't want to come off it

if its gonna break , this is the time to break it, before you own it.

listen to the engine, feel for smooth acceleration and smooth gear changes.

use any abnormalities or faults as a bargaining chip and beat him down on the price.
or walk away and look at another one
good luck


Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: Chaos on January 27, 2021, 10:59:07 PM
if it has abs it may not be an 85, hard to imagine retrofitting that especially since the 85's were a bit oddball with lots of unique parts compared to later years.  May be a titling mix up. but hey, if it runs good and feels good that may be a bargaining point!
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: Krautpleaser on January 27, 2021, 11:29:03 PM
greetings...

sounds sketch...

photos and vin please..

j o

VIN WB1051306F0042357
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: The Mighty Gryphon on January 27, 2021, 11:35:09 PM
K bikes, especially the early ones had odometer issues so I would be wary of the mileage.  It's not unusual that the speedo was changed out, restarting the mileage count.  A lot of the bikes that warranty speedometer replacement had a tag on the rear cowl near the paint code with the date and the mileage of the old speedometer. 

Do you have a link to his advertisement?  What is the asking price?  As the others have mentioned, this may be the only '85 in the world with ABS.  It could be added if you have all the parts, but I would be wary since adding it requires messing with a lot of the bike's wiring and brake system.

Does Georgia record the engine number on the title?  You might want to check both the frame and engine numbers.  A couple years ago I had my '92 K100RS totalled in an accident, but the engine and a lot of the brakes and wiring were still good so I got them from the insurance company and rebuilt the bike on a '91 frame that I got with a clean title.  I was able to sell the finished product for what I had in it, and had the satisfaction of saving a bunch of parts as a complete running bike.  It's possible that the bike in question is the marriage of parts and engine from an '88 or later which had ABS and a frame with clean title from an '85.  A couple good photos would help the eagle eyed inmates here to spot any parts that are not native to an '85 K100.
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: The Mighty Gryphon on January 27, 2021, 11:42:01 PM
I don't see any ABS hardware on your bike. 

I attached a photo of a bike with ABS 1, the first version.  Above the footpeg plates are the big modulators that pulse the brakes.  Also, on the front and rear wheels are toothed discs with a sensor.  I don't see them in your photos.   Not a big deal that it's not there.  In fact, not being there probably means the bike is in unmolested original condition.  IMO that's a good thing.


* BIKES 011 (2).JPG (64.45 kB . 768x544 - viewed 671 times)

The bike looks to have an aftermarket exhaust, probably a Staintune.  It's a bit louder than stock, and changes the power band a little from what I hear.  While I am not a fan, some riders like the exhaust sound with it.
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: blackie1 on January 27, 2021, 11:44:17 PM
I think it looks great  icon_cheers
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: The Mighty Gryphon on January 27, 2021, 11:46:35 PM
Looking closer, I see a Works Performance rear shock.  I have had them on a couple of my Bricks.  It's a pretty good shock, much better than the original.  They are rebuildable and can be done at home with about $40 in parts and a few more bucks to have the gas charged.  Most of these old bikes have aftermarket shocks by now, so it's not really that big of a selling point, IMO the only rear shocks that get a premium on the price are Wilburs and Ohlins.  This one just means you won't have the expense of replacing a worn out OEM unit.
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: The Mighty Gryphon on January 27, 2021, 11:55:47 PM
Mileage looks okay at 52K.  Engine should be just about broken in.  Looking closer, I still can't see the sensor rings or sensors for the ABS.

It looks like the rubber on the shifter has a cable tie around it.  Why?  The tragkorbs look pretty cherry, so possibly the paint on the rest of the bike is original and the bike hasn't been down.

The seat looks to be a Russell Day Long.  This is what I consider the best long distance seat you can put on one of these bikes if you plan to do some serious horizon chasing.  Should be worth an additional $100 on the sale price.  A good one goes on eBay for $200+.

All in all, the bike looks nice.  If it were mine to sell, I'd ask for $2300 and try to get at least $2k for it.  Whip out a stack of Hunnerts, offer something and make him talk you up, be prepared to give him your phone number and walk away.  It's a $2100 bike, tops.
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: volador on January 27, 2021, 11:59:55 PM
Bike is a K100RS (K589)      VIN:0042357  Produced: 02/85  USA

To verify the year made, enter the last seven digits of the VIN at Max BMW then hit 'ENTER'    https://shop.maxbmw.com/fiche/PartsFiche.aspx

The 1985 K100 is a 1-hit wonder. Your main concern will be with the 'Fuel Level Sender'. This part is no longer available and the archilles heel of the 1985 K100.


EARLY FUEL LEVEL SENDER  (http://www.motobrick.com/gallery/2/1601-100320202513.png)

EARLY FUEL LEVEL SENDER O-RING (http://www.motobrick.com/gallery/2/1601-100320202625.png)


How to fix the fuel level sender   http://www.motobrick.com/index.php/topic,12340.0.html

Under side of a 1985 tank  http://www.motobrick.com/index.php/topic,13775.msg123483.html#msg123483


Notable differences of the pre-85/86 K100 are the seat pan design with matching tail cowl section, the water/oil pump design changed, throttle cable design and fuel tank/fuel level sender/fuel return check valve.


Your '85 may have the European "hotter" cams known as "Finest Year K"

http://www.motobrick.com/index.php/topic,3653.msg21985.html#msg21985

https://forums.bmwmoa.org/showthread.php?4534-Why-is-the-85-K100-the-quot-Finest-Year-K-quot&s=66f149b3cadea44550d51fbf0b9ee793&p=42512&viewfull=1#post42512

The pre-1985/86 has molded pillion handles as part of the seat pan, metal or plastic seat pan.
Post-1985/86 removed handles from seat pan and added handles to the tail cowl section.


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


Throttle cables have 2 versions and lower brackets. Cable lengths vary with handlebars.
#1 version- have a adjustment sleeve approx. halfway down length
2nd version black plastic collar at the lower end or a white plastic collar

Pre-1985 fuel tank has a rear mounting tab later removed.
Early fuel lever sender is a thermistor type later is a float type.

http://www.kforum-tech.com/how-to/Modification%20for%20early%20gas%20tank.htm

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


Good luck on your buy

PS; looks like a SuperTrapp or Mac Performance Kerker style muffler & header

NO ABS on this moto
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: Krautpleaser on January 28, 2021, 12:15:45 AM
wow people. awesome info. riding the bike on friday. if it feels like i think it will, let the haggling begin  112350
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: daveson on January 28, 2021, 02:19:00 AM
The look of it tells me that the previous owner loved his bike, that's a big ticket item. The trip meter reads 333 miles, that makes me think the gearing might be broken and the mileage questionable. See if you can reset it to 0. See if the mileage is still 500 after your test ride, then ask if it's genuine. The shocker replaced also makes me wonder if the mileage is genuine.

The test ride is a good chance to find out the most about its history. If it has receipts they might mention work required for next service, eg. mileage broken, head stem work, etc. I'd check the mileage on the receipts too, it might have been 50,000 ten years ago.

Is that exhaust like one of those bloody k1100 things that crack in anticipation if there's even a rumour that someone's about to look at it with a frown?
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: koapono on January 28, 2021, 06:02:20 AM
Greetings, I have an 85 RS, same color as the one pictured. I currently have 206,000 miles on the original gauge cluster. Yes, they are prone to issues but after you take it apart a time or two it becomes quite easy. Otherwise the bike has given me no problems, ever. I do my own wrenching. Aside from wear and tear items, the occasional shaft-spline lube, ONE clutch and monkey-nut (alternator drive coupling) replacement the bike is original. I believe it was assembled by elves and fairy-folk in some magical Bavarian forest!
The bike pictured appears to be in great shape, previous owner seems to have paid attention to it:
Stainless brake lines up front, fork-brace, upgraded shock and seat. The muffler is not OEM.
As mentioned by others, I see no indication that ABS has been added to bike: sensor rings, modulator, etc.
The dash pad is not the same as mine, though mine is an early-model 85.

take the plunge!
G'luck
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: Laitch on January 28, 2021, 09:12:21 AM
The Russell seat has an excellent reputation and the rear shock is more desirable than a stock one. The custom exhaust is probably OK. The troubling part is that the "Guy" asserted it has ABS but—as indicated by members on this thread—it doesn't. That calls into question any other claim made about the moto from the seller. Look for gasoline leaks around the underside seams of the fuel tank and don't depend on the fuel level lights to give an accurate reading of fuel level. The sender in the tank was replaced by a more accurate device in later models and the fuel tank was redesigned to accommodate it.
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: Chaos on January 28, 2021, 09:33:57 AM
looks like a supertrapp muffler, tends to blacken the rear wheel because it is short and blows gas to the sides.  adjustable back pressure and noise by adding/subtracting plates but I never took a liking to the one I had.  Interesting how many 85's pop up here, they're also known as FYK  (Finest Year K)
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: Krautpleaser on January 28, 2021, 11:10:44 AM
Another total n00b question: how do you clean this bike? I have a pressure washer, but don't want to hurt it. Which products do you use for which parts, and how much effort do you put in it, on a scale from toothbrush to waterbucket?
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: volador on January 28, 2021, 12:03:14 PM
Use a soap made for 'car washing', no dish soap. Toothbrush, toilet brush works good on the wheels, Home Depot, Lowes, Amazon have all sorts of cleaning brushes and shop towels for cleaning in home cleaning section.

A compressor is useful to blow off the top of the engine tends to collect all the road debris and sand, etc... and the radiator up front.

The handlebars and dashpad look to be changed to the "C" type handlebars. A slightly more upright, comfortable for long distances riding stance.

Your quality of life depends on the quality of your effort. Success is not given, it is earned, and it is DESERVED. Don't rub the paint off...
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: alabrew on January 28, 2021, 12:07:21 PM
Wash it? Ride it in the rain., duh. =-}

Welcome from Birmingham. Good looking moto.

+1 on what the other have said to look for.
Check the date codes on the tyres and also check the condition of all the rubber bits.
Never hurts to change the fuel filter (NAPA Gold)
Look at the sticker under the seat to see if it is a 49 state bike, or 50, to determine if it is a Finest Year.
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: The Mighty Gryphon on January 28, 2021, 12:15:21 PM
I've been using S100 for far longer than I've been riding K bikes.  I use it on almost everything around the house from our automobiles to the lawn mower and the tractor.

When I get a "new" bike, I do a complete tear down of the fairing and as much of the mechanicals as I feel motivated to do.  It all gets a spritz or two of the S100 a wipe with a sponge or a gentle scrub with a soft brush and a good rinse.  This stuff quickly gets down to the original finish with almost no effort on my part.  It's pretty gentle and hasn't hurt anything I've used it on.  It's sold by Hardley Dangerous dealers, and I think you know how fussy the Hardley riders are about their rides.

Avoid pressure washers, they are the invention of the devil, and will cause much pain.  I use the lightest spray from the garden hose that removes the soap suds from the bike.  Take longer to rinse completely rather than blast quickly with a powerful spray.I have a collection of old towels that are used only for drying my bikes.  I wash them every time I use them.  I also have a bunch of microfiber towels for stuff like waxing, and detailing(when the spirit moves me).

I use Zymol cleaner/wax.  It lasts a long time, but isn't difficult to remove when painting is done.  I have also found a product called Back To Black that darkens and brings out the black in the bike's trim.  I use it once a year on all the black parts on the bike, turn signals, rear mudguard, fairing knee pads, engine cases, etc.  Works great on plastic, chalky paint, and the "rubbery" stuff.  DOn't use it on the seat though because it can make it pretty slippery.

As a maintenance thing, get a can of Deoxit spray and try to give every electrical connection a squirt to clean up any corrosion.  Also get a can of copper anti-seize and use it on every bolt on the bike when ever you take anything apart.
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: Krautpleaser on January 28, 2021, 12:27:58 PM
Excellent. I'll concoct my routine from these suggestions.

Last one for now: what's the most obvious thing to point to when telling my guy that this bike does not have ABS?

I am now convinced the he was just lazy (as opposed to intentionally lying... yes, i'm a bit of an idealist) in his sales description, given that his main business is selling much more pricey bikes. I've already laid the groundwork for my haggling with correcting him on the year of the bike (and if this really is the FYK, i'm just fine with that  :laughing1:), but could make a bigger deal out of the lack of ABS (which again, i'm not really sad about, given the troubles some have reported)
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: Chaos on January 28, 2021, 12:55:56 PM
Here's the KBB price as a starting point, I wouldn't go much higher.  S100 is great but pricey, Orange spray cleaner is usually only a couple bucks, cuts grease, smells nice.  Brand doesn't seem to matter and available everywhere.
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: Laitch on January 28, 2021, 01:29:42 PM
Last one for now: what's the most obvious thing to point to when telling my guy that this bike does not have ABS?
It doesn't have an ABS pressure modulator on each side of the moto which is characteristic of ABS1 on classic 2 valve Bricks. See photo below. There's no substitute for those modulators. Make him show you what runs the ABS. That should be educational. Personally, I'd move on.

As far as the label "Finest Year K" is concerned, read this (https://forums.bmwmoa.org/showthread.php?4534-Why-is-the-85-K100-the-quot-Finest-Year-K-quot&s=cb00ca93f408438090bc01033fc3ad55&p=42512&viewfull=1#post42512).
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: The Mighty Gryphon on January 28, 2021, 02:16:54 PM
These are the parts you need for ABS:

1. Pickup ring for wheel speed sensor
2. Modulator controls brake pressure when wheel locks up
3. The "brain" that controls everything is an electronics box that hides in the tail cowl.

 [ Invalid Attachment ]
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: Krautpleaser on January 28, 2021, 04:06:11 PM
So, just look for the cans clearly labeled "ABS"... got it  44271
Great background on FYK. If I love the bike, I'll totally go with the myth :)
But it does explain why he might've advertised it as 86, which is def sketch.
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: daveson on January 28, 2021, 04:37:37 PM
Possibly first registered in '86, which is an innocent explanation.

Bricks were the first bikes in the world with ABS. Maybe he read this, which is true, but I think it was optional.
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: rbm on January 28, 2021, 08:18:29 PM
These are the parts you need for ABS:

1. Pickup ring for wheel speed sensor
2. Modulator controls brake pressure when wheel locks up
3. The "brain" that controls everything is an electronics box that hides in the tail cowl.
4. pickup ring on front rotor and visible sensor mounted on left fork leg.
5. small blue relays in the relay box.
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: Chaos on January 28, 2021, 09:14:43 PM
These are the parts you need for ABS:



annoying flashing red light in speedo pod
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: The Mighty Gryphon on January 28, 2021, 11:05:39 PM
Yeah, the flashing light.  I only mentioned the parts in my photo.  Obviously, if they're not there, the bike is unlikely to have ABS. 
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: volador on January 29, 2021, 04:13:00 PM
BMW ABS app works on iPhone 12 and Android 10.

Just installed the ABS app on my iPhone 12 Pro. Need to synchronize with Bluetooth v5.0 ABS sensors on the 84...
Title: Re: Hello. About to pull the trigger on a 85 K100rs. Any wise advice for the n00b?
Post by: alabrew on January 29, 2021, 05:30:07 PM
Looks like it is at Blue Moon Cycle in Norcross, GA.
https://www.cycletrader.com/listing/1986-BMW-K100RS-5014821717
Surprised they would make those errors, they should know better, they have been around a long time and have a vintage museum.