Hey all, I am finally starting my '85 k100 gravel runner project.

[jimmyx]

I am trying to hunt down a good dual sport tire and am wondering what the largest tires I can go with. It looks like 110/80/18 front and 140/80/17, any other thoughts? I am also in the process of replacing the fuel pump, filter, and mounting hardware (rubber damper, support ring,hoses,etc.) I have purchased a less expensive,smaller diameter pump, foam sleeve to adapt to damper and filter and a set of remanned injectors. any tips on the install of this set up would be great!
Thanks,
Jimmy

[jimmyx]

Sorry, just found tire recommendations. Any tips would still be cool though....

[jimmyx]

I'm thinking Bridgestone TW26 110/80/18 front
And Kenda Big Block 130/80/17 rear.
           Or.....
Kenda 761's

[Grim]

Make sure you post up some pics when you are done.  I have a LOT of FS roads nearby and thinking about a dual sport conversion. Actually made an offer on a crashed LT today and found a nice tight small fairing on Craig's  to get the big LT fairing off it.  See if my offer gets accepted 


Won't let me imbed but check this one out. http://www.motorstown.com/images/bmw-k-100-01.jpg

[tg4360]

I've got an R1150GS Rear on mine.  Bolts right up once you remove the rotor.  You'll need also an R1150 rear caliper and have to remove a little from the caliper bracket but it works a treat.

You'll also be sans centerstand unless you move it.  I moved my K1100 centerstand down and left an inch and ground a little of the feet to fit the tire.

Do it and don't look back.

TG

[jimmyx]

I've got an R1150GS Rear on mine.  Bolts right up once you remove the rotor.  You'll need also an R1150 rear caliper and have to remove a little from the caliper bracket but it works a treat.

You'll also be sans centerstand unless you move it.  I moved my K1100 centerstand down and left an inch and ground a little of the feet to fit the tire.

Do it and don't look back.

TG
[/quote
Hey TG,
What did that 1150gs rear set you back? Are you running a 21" front? I herd tell it can't or shouldn't be done. I would love to see a few photos .
Thanks,
Jim m

[jimmyx]

Make sure you post up some pics when you are done.  I have a LOT of FS roads nearby and thinking about a dual sport conversion. Actually made an offer on a crashed LT today and found a nice tight small fairing on Craig's  to get the big LT fairing off it.  See if my offer gets accepted 


Won't let me imbed but check this one out. http://www.motorstown.com/images/bmw-k-100-01.jpg

Hey Grim,
I will post up as I go, I ride an '01 xr650r as a DS. I would like to make this ride capable of hitting double track/ dirt roads. Plans so far are as follows ;
 Super Tenere low front fender, trail tech 8" race light(used), the biggest DS tires I can fit under it, change and tube the rear end. Some sort of rear fender , solo seat(custom), powder coat wheels black,
Moto bars, aftermarket DS speedo, rally type exhaust, beef up Suspenion, paint will be Army grey and black. This is all subject to change, of coarse. Here is a shot of my XRR.

[tg4360]

Hey TG,
What did that 1150gs rear set you back? Are you running a 21" front? I herd tell it can't or shouldn't be done. I would love to see a few photos .
Thanks,
Jim m

I got a screaming deal on an R1150 front and rear for 450bucks on Ebay.  I gave the front to a riding buddy for his birthday so now he uses it to swap between a Tourance and TCK on his GS.

The front of my bike (Forks, trees and wheel) are R80/100GS which is a 21" front rim with a second right slider adapted to the left side so I can have two brake calipers. 

I'd like to know who said it couldn't be done because I wonder what it is I've been riding around all spring summer.....

Pics here:

http://www.motobrick.com/index.php?topic=580.msg34354#msg34354

[jimmyx]

Very nice TG! Did the triples swap right over bearings and all? Or was there milling involved? I hunted down your photos, so cool. The stock forks are wicked flexy, is the upgrade more stable? No issues with 21" front touching oil stuff (technical language )on motor?

[tg4360]

Very nice TG! Did the triples swap right over bearings and all? Or was there milling involved? I hunted down your photos, so cool. The stock forks are wicked flexy, is the upgrade more stable? No issues with 21" front touching oil stuff (technical language )on motor?

The bearings and headstock dimensions are identical.  I pulled off the K100 trees and fit the R100GS trees.

Only two things needed to be done and that was clearancing the bottom tree to not touch the steering stop (This may just be on my bike as they are a welded on tab and it may not be a factor on other bikes) and I removed the actual steering stops and replaced them with a 6mm cap screw and nut in order to keep the bottom tree from hitting the rad support.

No clearance issue with the tire and pump or rad.  I've added a home made bash plate since that picture and the tire doesn't come anywhere near that either.

The rad shroud is from a K75 and it's cut and fit so there's no center section as it appears that if you even could find a K100 shroud (Rare) the center trim part may foul the fender. 

You could always use a low GS fender though.

As for stability, the front is a solid and compliant at the same time.

The stock GS fork is compression on one side and rebound on the other.  I put Racetech gold valves in both sides with rebound dampers in both so now I have compression and rebound on each side and it's fully tunable.

I think the fork brace is key also.


TG

[jimmyx]

Got 'r running! Cleaned all black gunk out of the tank....I did the $30 fuel pump swap, fuel line in tank(also $30 for one foot@ Napa), new fuel filter and line to the fuel rail, tough to start at first with weak battery. it ran pretty rough and smoked a bit then stalled. I pulled the plugs, wet with gas and thick carbon gunk. Cleaned plugs and tried again, she started but still smoked, ran rough at low rpm.
Finally I swapped in the rebuilt injectors, cleaned the fuel rail and installed new plugs. Fired right up and ran pretty smooth then stalled again. The problem was the 4 prong connection @ the fuel tank, the female connectors were spread out and a bit loose! So far so good....I also installed the new rear brake reservoir and bled the rear brake.... Good to go.
Next up are the final drive and spline lube, oil change and radiator flush.
I installed a Trail Tech, h4 (has high and low beam)set up on the bike. Some photos to follow!

[jimmyx]

Old, cruddy parts! New light and other.

[jimmyx]

Next parts are... Super Tenere low front fender, Koso digital speedo( small dual sport style) so I can ditch the big, goofy instrument panel. Fork boots, and solo seat(I need to cut and Fab the rear frame.) as for tires I think I will go Kenda Big Block rear and Trail Wing front, bolth fairly aggressive DS tires. I think I will powder coat the wheels black or dark grey. And lastly, for now will be some sort of moto bars.

[johnny]

 

[tg4360]

Hey Jimmy,

The hot setup for the rear MC reservoir is to get the newer res and strap it to the frame under the right side cover.

Gets it out of the sun and out of the way.

I got one from Bike Bandit along with a few other odds and ends and just added a longer hose.  Cleans up the right side of the bike and the res is more protected.

[jimmyx]

Good idea TG , The other was so brittle it  just fell apart. I had to get this thing running again before I invested any more cash. I will add that to the list, It'll be good to keep it out of the sun.

[jimmyx]

Hey guys,
A couple of questions.....I. Am trying to swap the instrument panel for a small Koso unit, does anyone know what wires I need to bypass or hook together so I can start the bike without the old  instrument panel on. Also ... How do you remove the ignition switch (tumbler) from the plastic housing? (Sawzall ?)
Lastly, I swapped the bars for moto style bars. The problem I am having is, the throttle tube is hanging on the new bars making the throttle stick. The throttle did not hang on the old bars and there doesn't seem to be any cable length issues. I greased the geared throttle mechanism, sanded the bars some, (which helped) and I cleaned the tube up. The throttle is still sticking /hanging. Do I need to
Sand the bars more? Pics to follow....
Thanks you,
Jimmy

[rbm]

A couple of questions.....I. Am trying to swap the instrument panel for a small Koso unit, does anyone know what wires I need to bypass or hook together so I can start the bike without the old  instrument panel on.

Pull in the clutch.  To start without pulling in the clutch, you'll need to construct a Start Enable emulation circuit.  Read this post:
http://www.motobrick.com/index.php?topic=1452

Lastly, I swapped the bars for moto style bars. The problem I am having is, the throttle tube is hanging on the new bars making the throttle stick. The throttle did not hang on the old bars and there doesn't seem to be any cable length issues. I greased the geared throttle mechanism, sanded the bars some, (which helped) and I cleaned the tube up. The throttle is still sticking /hanging. Do I need to
Sand the bars more?

Are they 7/8" chromed bars?  If yes, 7/8" is 22.2mm which is 0.2mm too large for the handlebar controls.  You need to remove the chrome plating completely for the throttle tube not to stick, assuming 7/8" bars.

[jimmyx]

Thanks so much Robert!
Good info here. I didn't know about the clutch trick, I may have stretched the cable a bit when installing the bars, but I think it's the Grey anodization. I sanded all of that off already, I will will get after it again. I do not have a throttle cable adjust at the perch end, is the slack adjuster somewhere behind the air box? It looks as though the choke is on the left of the fuel rail.
Thanks again,
Jim

[jimmyx]

One quick question, for now.....If I decide to go the clutch start method, can I simply cut and heat shrink all of the wires I am not using on the new Koso speedo unit?

[rbm]

On the early bowden cables, the adjuster was midway in the cable.  Later bowden cables put the adjuster on the perch.  Yours is probably the former.  Look for it midway along the cable.

As for getting the ignition switch out of the plastic cylinder, read this document:
http://technik.flyingbrick.de/images/6/6f/61_zuendschloss.pdf

[rbm]

One quick question, for now.....If I decide to go the clutch start method, can I simply cut and heat shrink all of the wires I am not using on the new Koso speedo unit?

Yes. 

If you're going to do that, may I suggest that you fold the end of each wire back upon itself and slip a short piece of 1/8" diameter heat shrink over the folded end.  Shrink it in place.  This way, it is not possible to accidently short a live wire and burn up the harness.  This is not so far fetched; I know of someone who actually did nearly burn up their harness even though the end was snipped.

[jimmyx]

Sound advice Robert,
Thank you.
Jim m.

[rbm]

I want to modify my unconditional "yes" to a Conditional "yes" on second thought.  Are you hooking up Charge Lamp - Pin 9 (Blue) to a bulb or LED to switched +12V - Pin 6 (Black/Green)?  If not, then do this.  Otherwise your battery will not get charged.

[tg4360]

As for the ignition switch....

The black plastic bezel on the front will pop off and then you can see how the switch is pushed in from the rear.

It's a little fiddly but once you take the pad loose and look at it from both sides you'll see how to get it out.