Author Topic: 90 K75S Cafe Build (Read 33456 times)

kryder · « **Reply #25 on:** May 11, 2016, 08:45:34 AM »

If a motorcycle is "cafed" the right way then good. There are many beautiful BMW cafe racers out there, however the majority are butt ugly. In my opinion the K75S with a Corbin gunfighter seat or the BMW model seat that is similar looks very cafe already. The "S" designation has always looked somewhat cafe racer going back to the R90S. I see many converted motorcycles on Craigslist that are for sale at prices way above original models that I suspect never sell. It takes great skill, money, time and dedication to come up with an excellent and appealing cafe racer. Most fail at this, excepting the professionals of course. They lose interest and run low on funds. That said, I wish the O.P. success and await the final result.

Quiltzig · « **Reply #26 on:** May 18, 2016, 03:50:26 PM »

Interesting variety of comments on whether or not to save or totally change the K75. Here is my take.

I have a mint condition, low miles 1990 K75S which I am keeping as a collectors item, but it is still being regularly ridden, as it is just such a lovely smooth bike. I have found tragkorbs for it and had them colour matched (Onyx Schwartz) it has been brought up to Concours condition and recently won an award for best bike at a BMW rally.

Recently I found a slightly older 1987 bike that was rather sad. It had a leaking fuel tank, which the PO had tried to fix with some "goop" (unsuccessfully). It was missing fairings, had a rear brake reservoir from a car with crappy budged up hoses, blocked extra outlets and various other home made very poorly done jobs. It was pretty sad looking. There was so much corrosion on some parts (battery tray) that they were just not able to be saved. I am turning this bike into a cafe / street fighter look for several reasons.

1. I love the look of the brick motor and the smoothness of the bike.
2. I am getting older and want a lighter bike, but it must be a K
3. This bike will provide spares for others, and help keep them going.
4. I need something to keep me busy over winter.
5. There seems to be a ready market for well executed cafe designs based around the K. Recently a really sharp looking K100 cafe racer sold here for NZD $6800

Turbo224 · « **Reply #27 on:** May 26, 2016, 12:47:24 PM »

I finally got around to tearing into the bike this week. Purists turn away, you wont like what you see. First thing I did was pull off the front fairing and handlebars. I actually like the look of the belly pan still on there, so I am going to leave that on for the time being. I bought a set of strap-ons and a set of clubman bars because I didn't really know what was going to work. I personally don't like the way strap-ons look, so I started with the clubmans. These are just a set standard 7/8" bars. I didn't want to file out the stock controls in case someone ever wants to put this bike back to original, so I just sanded off the powder coating on the bars. Once the powder coating was removed the controls slide right on the bar. The result? I guess they looked okay, but the shape of these bars just made for a terrible ridding position. Sorry the pictures suck, I was working in my house garage which has terrible lighting instead of the shop.

Turbo224 · « **Reply #28 on:** May 26, 2016, 12:58:57 PM »

Next I tried the strap-ons. I lowered the front end of the bike a couple inches and had the bright idea that I should just mount the strap-ons to the top of the trees. The results make for a much more comfortable seating position, but the overall look doesn't quite fly. Seeing that I rarely go on long rides, I am going for form over function. I'm going to go ahead and move the bars to underneath the steering head tonight and call it good. On a side note, does anyone know if any steering head from a K100 or K75 will swap onto my bike? Mine is particularly ugly since I cant remove the bar mounts.

Quiltzig · « **Reply #29 on:** May 26, 2016, 04:57:14 PM »

One suggestion... why not use the bar mounts as the mountings for your instruments (if you are planning on using new ones) - this would kill 2 birds with one stone.
Do you find the riding position too far forward with the Clip Ons?
I am just starting work on a K75S Café build now, and those bars are a continual question in my mind. I want to be able to do some longer runs on it, take it to shows etc, and my ageing body is going to protest too much methinks.
Any others got suggestions on this?

Turbo224 · « **Reply #30 on:** May 26, 2016, 05:20:30 PM »

Quote from: Quiltzig on May 26, 2016, 04:57:14 PM

One suggestion... why not use the bar mounts as the mountings for your instruments (if you are planning on using new ones) - this would kill 2 birds with one stone.
Do you find the riding position too far forward with the Clip Ons?
I am just starting work on a K75S Café build now, and those bars are a continual question in my mind. I want to be able to do some longer runs on it, take it to shows etc, and my ageing body is going to protest too much methinks.
Any others got suggestions on this?

You actually hit the nail on the head. I'm going to temporarily mount the stock gauges right on top of the head so I can hide the ugly and the bike will be legal. The plan is to use an aftermarket gauge at some point in the near future, so when that time comes i'll replace the head with one of the cleaner units.

Where the strap-ons are located right now is actually okay, I could go on a long ride with how it is setup right now. Once they are mounted below the head it might be a different story. Then again, a cafe racer was never meant to be a long distance bike, they are basically bar hoppers.

johnny · « **Reply #31 on:** May 26, 2016, 05:22:39 PM »

check your moto geometry and your ride height for whack if you decide to leave those strap-ons like that..

colly · « **Reply #32 on:** May 26, 2016, 08:27:04 PM »

How do you do this exactly Johnny?

johnny · « **Reply #33 on:** May 26, 2016, 09:07:57 PM »

1st... if you caint deploy the sidestand its too low...

Quiltzig · « **Reply #34 on:** May 26, 2016, 09:21:25 PM »

Most K75s that I have seen (including the two that I own) have quite an alarming amount of lean when on the sidestand. On my wifes bike I have added a 10mm packer under the foot to lessen the angle slightly as she has trouble lifting it up to vertical.

Martin · « **Reply #35 on:** May 26, 2016, 09:24:43 PM »

As well as the side stand, you might not be able to get it onto the centre stand, if you intend to keep it.
Regards Martin

TrueAce · « **Reply #36 on:** May 26, 2016, 11:07:00 PM »

Can't really tell how much you have lowered the forks, but it looks to be significant. That shifts weight to the front and really affects the handling. The geometry between front and rear is messed up with forks too low...........might require a shorted rear shock, various lengths are available. Consider a straight short sport touring bar, which you can find in BMW diameter.

Martin · « **Reply #37 on:** May 27, 2016, 02:08:22 AM »

Lowering both front and rear significantly will result in less cornering clearance. Might look good but the bike will be slower through the twisty bits.
Regards Martin.

colly · « **Reply #38 on:** May 27, 2016, 04:27:37 AM »

I was planning on doing similar to this: http://i.imgur.com/3E8SlyS.png - about 20cm at the front - is that ok without causing whack?

Laitch · « **Reply #39 on:** May 27, 2016, 06:38:34 AM »

Quote from: colly on May 27, 2016, 04:27:37 AM

I was planning on doing similar to this: http://i.imgur.com/3E8SlyS.png - about 20cm at the front - is that ok without causing whack?

It's going to change the handling, colly, as Martin, Ace, johnny and many articles found researching "motorcycle geometry" have indicated. The significance of the change will be experienced when riding it. You'll need to be prepared to alter it again for safe and practical riding.

A conservative approach as Ace has indicated will be the least costly and safest.

Turbo224 · « **Reply #40 on:** May 27, 2016, 03:23:41 PM »

Thanks for all the comments. It will definitely be interesting once I get it back on the road. I'm sure I will have to go back and readjust everything to make sure it rides correctly. I changed the strap-ons to below the steering head yesterday and it certainly LOOKS much better. I was worried these would sit far too low for me to ride the bike comfortably. When I removed the seat and rear tail section to start fabbing up a new pan I realized that a much lower seat will make these strap-ons much more livable. I'll be working on a seat pan and rear tail section over the weekend.

mw074 · « **Reply #41 on:** May 29, 2016, 08:54:38 AM »

I have lowered K75s front and rear for women. I noticed a handling change but the women didn't. The K bike kick stands seem to bend fairly easily. They can be straightened out on a press, but over time they will start to bend again. Don't stand on the peg to get on or off if not on the center stand.

Turbo224 · « **Reply #42 on:** May 31, 2016, 06:11:01 PM »

Worked on the K a little bit this weekend. I removed the rear tail section and got rid of all the brackets and mounting bits I no longer need. I also started working on the new tail section, it's just set in place for now until I decide how I want to attach it. Once I get it mounted I will try to get the bike out in the sun for some decent pictures. Comments and criticisms are welcome. :2thumbup:

Turbo224 · « **Reply #43 on:** June 01, 2016, 01:07:13 PM »

Spent some time mounting up the headlight and front turn signals yesterday. Standing back and looking at it, I feel like the headlight needs to be lowered. Thoughts?

Quiltzig · « **Reply #44 on:** June 01, 2016, 04:56:06 PM »

Yes, agreed, the headlight should be centred on the tank when viewed from the side.
What make & model is the headlight from?
Any pics of the clip on mounts and top triple T?

Turbo224 · « **Reply #45 on:** June 01, 2016, 06:49:32 PM »

Headlight is from a Yamaha MT-03. There are a few pictures earlier in the thread of the strap-ons, I can snap more if you are looking for something specific.

Turbo224 · « **Reply #46 on:** June 10, 2016, 09:06:38 PM »

A few pictures out in the daylight. Still lots of little things that need to be done, but at least I can ride.

Turbo224 · « **Reply #47 on:** June 10, 2016, 09:16:59 PM »

I made my own seat cushion and cover. For the pad i used a memory foam gardening mat that I picked up in the gardening section at Walmart. I bought the black vinyl and thread at Hobby Lobby and stitched the pattern myself on a borrowed sewing machine. The base is made from some scrap panel board i had laying around. Cheap, reasonably comfortable, not half bad looking. Also a picture of how I mounted the ignition switch for now.

TrueAce · « **Reply #48 on:** June 10, 2016, 09:51:01 PM »

Nice work........the headlight really fits well. Very clean look.

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Author Topic: 90 K75S Cafe Build (Read 33456 times)