My ugly BMW k100

Finnigan

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I decided to start a thread on this. To say I got this cheap is an understatement it was basically free; its a 1990 BMW k100LT. I had to ditch my last build because of budget issues (taxes, car repairs, vet bills). Anyway I have no idea where I'm going with this bike but its something to ride and, even though I haven't seen any evidence of it, it has 1000cc's. She runs like shit and is ugly as an ass wart.
 

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I rode her for about 2 weeks before I started pulling things off, it was great having luggage to get groceries on but its a bike not a mini van. The first thing I wanted to do was cut down on how big it was and get rid of the windscreen that was so crudded up I couldn't see through it...and I felt like an old man with the upright riding position. Fairing off and luggage and unessessary weight off. I must have taken 50lbs off her and she looks better already in my opinion.
 

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I decided to put superbike bars on her, I had them laying around so I ordered some cheapo rear view mirrors from fleabay and its starting to look alright...?
 

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Throttle response is shit and I can't seem to sync the throttle boddies so I spent a little dough to get new injectors. Instead of a 24 year old 1 hole spray these babies have 4 and were synced to each other. The ad said they were for a 318i (I think) but would fit my motor, here goes nothing!
 

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Took the bike for a ride after the install and to say its faster and more responsive is an understatement, she is amazing now! The motor feels so 'happy' now and the power is immense! So much so that it makes me want to spend a little money on some better brakes :D
 

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The paint is such crap on this that I'm debating changing the color. I got a quote to paint it for $850, yeah fucking right buddy. I started researching some ideas and came up with this 3M vinyl car wrap, what do you think of the color?
 

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Those K bikes look so much better without the stock windscreen IMO, big improvement. I have a buddy with a few K75's and he says the engines are extremely smooth, bet with those new injectors must be even better.
 
The engine on the bike is really great, very quiet with shaft drive but changing down can chirp the tires. Maybe thats par for the course with so much displacement and only 5 gears. I don't know if I trust the odometer since they were prone to failure but it currently reads over 129k miles, not bad!
 
Went for a short ride today and my dash bracket snapped in half when I hit a bump. Rode a few miles home with it handing by the wires
 

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There's loads of scope with the old Kay Bricks - I've done a factory Race Rep and a Cafe Racer [ both sold off ]. Currently working on my Streetfighter.

Check ALL electrical connections - under the seat and especially the connections to the instrument cluster - yours is already off ! They suffer really badly from corrosion - most will be furry green inside ! A good clean up and spray ith switch cleaner usually does the job. You can mount the instrument cluster off the lower yoke to lower it right down [ see my bike ] and hide some of the fuggly.

You can save over 100lbs from the fully faired bike. My bike is currently undergoing a final mock up ready to be stripped, detailed and painted. I'm also swapping in K1100 forks, so I can use K1200S 5 spoke wheels and much wider rubber. As a bonus - I get 4 pot Brembo calipers and larger discs.

See more details under "Streetfighters" threads.

 
headers, exhaust, headlight went on last night
 

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First ride with the new exhaust and I couldnt be happier with performance. The engine feels smooth and of course the sound is a big improvement. I took off 2 discs to increase backpressure and the rev range is MUCH improved. If anyone is thinking of getting a supertrapp muffler I highly recommend it!
 
Burned out and dim green gauge lights to bright red LEDs
 

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Macheined up some aluminum spacers for the front wheel, snug as a bug
 

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looking great! I'm doing pretty much the same cafe conversion to my dads old K100LT so i'll definitely be keeping a close eye on you for hints and tips ;)

couple of quickies though if you dont mind?
1.) when swapping out the injectors is it literally a straight swap? or are there other limiting factors? i.e. will the bike run too rich etc?
2.) did you face any difficulties with the GSXR front end? i love the idea of this but i'm just cautious about the work involved interms of the triple trees and bearing etc. as well as fork length
3.) have you thought about swapping out the final drive for that of a k100 RS? i hear it can give the bike a little more uuumph
 
Hey Gill,

Thanks for the encouragement.

1.) The injectors were very east to pull out and swap with new ones. I didn't notice any fuel mixture problems at all, the purpose of putting in new injectors is not for more fuel, but a better delivery. For example there are 4 smaller holes instead of 1 large hole, atomizing the fuel for a more complete burn. (or so I've heard)! In addition the new injectors were flow synced to each other so fuel going into each cylinder is identical, in case the 24 year old injectors developed problems
2.) The GSXR front end was incredibly easy to put in, I thought I'd have more difficulties. You can use the stock bearing races, order some AllBallz bearings with the diameter changes, and put the supplied spacers on the bottom of the stem to get close to the correct height then torque it all together to squeeze the bottom bearing into the correct position. All in all if there are any issues, I haven't encountered them yet!
3.)If i remember correctly the RS final drive has a 12% difference so that's not something I'm willing to spend the time and money on. I WOULD however be interested in puttin a k1100 paralever final drive on to eliminate the drive splines tearing apart.

Let me know if you have any questions and start a build thread so we can follow along!
 
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