BMW K100 Cafe Racer

[EF Ian]

1987 BMW K100 - Originally a K100LT

The K100 are actually quite cool I think, unique engine layout, engine used as a stressed member, single sided swim arm, shaft drive and super reliable. Should suit me well as a project.



So, I'd always wanted a cafe racer project, but hadn't planned on it for a few years yet, I saw this however and bought it on the spur of the moment. Its pretty much good enough to ride once I give it a full service and fix a few problems so it can get an MOT, horn not wired, speedo not working, master cylinder needing rebuilt, etc. Its not however up to my standards so I'll be slowly improving everything I can. For now I want to keep it on the road and only do jobs not requiring much spending.

Once the 260Z project is complete however I will strip this completely and rebuild from the ground up. I plan to alter the frame, seat, new rearsets, custom rear shock, fully rewired with an M-Unit, change the front shocks and brakes to S1000RR units and fully repaint and polish everything.

 

[Nickyyy]

Looks cool asf!

 

[quattro Rick]

Very cool. Was it advertised as being in mint condition?

 

[EF Ian]

Looks cool asf!

That what led be to buy it unplanned, love how it looks, and it can only get better.

Very cool. Was it advertised as being in mint condition?

Thanks.

I knew about the MOT issues before buying, My friend picked this up for me so I never actually saw it in person until I got home for leave. I think the seller thought it was better than I think it is, but I have higher standards than most but I don't think he ever said it was mint. Actually good to have plenty to do on it, thats what I wanted.

 

[quattro Rick]

That what led be to buy it unplanned, love how it looks, and it can only get better.




Thanks.

I knew about the MOT issues before buying, My friend picked this up for me so I never actually saw it in person until I got home for leave. I think the seller thought it was better than I think it is, but I have higher standards than most but I don't think he ever said it was mint. Actually good to have plenty to do on it, thats what I wanted.

I was more on about it being minty green

It still looks in brilliant condition tbh. Looking forward to seeing how it turns out though.

Always loved the Ducati sport classic, was actually the reason I got my test. But they're not cheap.

 

[EF Ian]

I was more on about it being minty green

Lol, I completely missed that one.

It still looks in brilliant condition tbh. Looking forward to seeing how it turns out though.

It is to be fair, I'm just a bit anal when it comes to these things.

Always loved the Ducati sport classic, was actually the reason I got my test. But they're not cheap.

They really aren't cheap. Plenty of other cheaper but very cool bikes with that same style, buy something close to how you like and build the rest yourself. I quite fancy an old Honda CB750 or CB550 and actually the old 125s can look awesome as can the older hornets with some work. I want something proper oldschool if I do another one though.

 

[Apis]

I like these a lot and agree that altering the frame would be a good move. I think they look so much better if the seat/top of subframe kicks up in a straight line with the bottom of the tank.
Love them with spoked wheels too.

 

[EF Ian]

These are now surplus to requirements.

 

[Apis]

These are now surplus to requirements.

Designer fold-up coat hangers.

 

[EF Ian]

Designer fold-up coat hangers.

They are available for sale if you want a set.

 

[EF Ian]

Been making some improvements

Thinking about doing the covers in glass black once I get a compressor setup here.

Hope you guy think it was worth it, this took a very long time to do, probably about 6 hours. They were very rough cast so had to start with a file and flap disc.

She got a wash the other day, I was very happy to have my Big Boi Blow-R Pro to help dry it.

Doesn't dry the wrap though. The exhaust had some form of bracket on it, but it was to short and wasn't attached to anything. Trying to work out if I actually need a bracket or if I can just cut it of and do without.

 

[Apis]

Maybe the bracket was for something like a bump stop for a centre stand that is no longer there.

As for that wrap, I know a lot of folk like it but personally, I'd have it in the bin.

 

[quattro Rick]

Is the hangar from the exhaust not what was attached to the rear set that you cut off?

 

[EF Ian]

Is the hangar from the exhaust not what was attached to the rear set that you cut off?

No, it was only attached to air. And there was no where it could have mounted on the rear set.

Maybe the bracket was for something like a bump stop for a centre stand that is no longer there.

On an exhaust? No, its there to support the exhaust, thats for sure, but that doesn't necessarily mean its necessary to be there.

As for that wrap, I know a lot of folk like it but personally, I'd have it in the bin.

Personally I like it and have used wrap on my cars for nearly 10 years with no problems. Problem with polished headers is the they tarnish very quickly.

 

[chopaholic]

This is great Ian, love how it looks. Dying to do the bike test myself.

 

[S2K-Aaron]

Looks Great Ian! A lot of hard work and things have been replaced already there so great project to start. I was helping a fella recently there with a K75 actually looks very similar.

Good luck with it! Maybe see you on the Honda some day

 

[EF Ian]

This is great Ian, love how it looks. Dying to do the bike test myself.

Thanks. Get it done, I'm sure a chap like you would love an excuse for another project.

Looks Great Ian! A lot of hard work and things have been replaced already there so great project to start. I was helping a fella recently there with a K75 actually looks very similar.

Thanks. Seems a lot of things have been done/replaced badly, attention to detail and care have not been a strong area for the person who did the work. Lots of minor issues I have had to fix. The poor thing needed a lot of love.


The k100s and K75 are very similar looking bikes.




I think the re shaped rear sets are an improvement.

I think I'll give that bracket the chop, it seems fine without the support and would look nice without a bracket being there.

Started to polish up the engine cover bolts to a mirror finish.

Upon trying to refit them I found some would not go back in, had to take the cam cover off, seems whoever had the cover off last had massively over tightened them, resulting in cracks on the cam caps where they thread in. They only need 8lbft of toque so easy to over torque if you don't use a wrench, possibly done to try and stop oil leaks as some of the washer had gone hard and brittle. Most of the bolts on the bike were so tight I had to use my breaker bar or impact gun to get them loose so hardly surprising. Guy had never heard of a torque wrench.

This could have been a disaster as it effectively meant a new head as the cam caps are line bored with head from the factory and are matched to that particular place on that particular engine so you can get new one or fit second hand ones.




Luckily I managed to come up with an easier solution. Which worked because the studs for the cam caps had plenty of extra thread left.

Got these machined out of stainless steel.

 

[EF Ian]

Decided to strip and re-paint the cover while at it because the paint was flaking off, was harder than expected, it had been sprayed over a silver base with a clear coat and was peeling due to barely any prep on the clear coat. Anyhow, the paint strippers I tried were pretty ineffective so this was a lot of harder and took a lot longer than expected, I now know why I normally get things blasted. (Can't wait to have my own blast cabinet)

I only had access to a single pak paint so I plan to re do it properly sometime when I can blast it and ideally once I get a compressor setup in the garage properly. Then I'll spray a decent satin or semi gloss 2K with good fuel resistance.

Also sprayed the ECU so it doesn't stand out below the seat.

Some of the service items.

Flushed the oil, re filled, new oil filter, new plugs, new fuel filter (one I removed had 99 date stamp so was likely pretty old. Gearbox oil changed, coolant flushed and changed with new thermostat, new oil in the rear drive.

Next lot will be cleaning and greasing the splines on the shaft drive and changing the boot on the clutch actuator.





Paint on casing and shaft leg was also peeling and lifting (no primer and poor prep will do that) so I re did a lot of that,

Other jobs done:

• Tabs on tank removed
• Battery tray cleaned up and painted
• Battery de labelled
• Lots of threads around the bike cleaned up
• Wired in a horn
• Got the button for the speedo working, no speed displaying yet, more work needed, waiting on some parts for this including the gear needed to wire in the tachometer.
• Brake callipers re painted and brembo logo sanded, these are due a re build
• Many bolts mirror polished
• Gear and brake levers had casting marks removed and then polished.
• New foot brake light switch fitted
• Improved some of the wiring but it was a right mess, still loads to do but until the full rebuild I'll limit this.

Hopefully you will agree it is looking better than before, took more photos but the colours came out bad.

 

[S2K-Aaron]

Looking better already mate. Have to get a look around it when she's done sometime

 

[EF Ian]

So after a lot more work than I had hoped I finally got this though the MOT and on the road.




Took a while to get the speedo working properly with the motoscope mini.

Final drive off to grease the driveshaft spines and to paint it.



BEP 3.0 wired in to sort out the mess of wires, make the stock speedo sensor work as well as the tacho I wired in.

Had a small leak from the radiator, managed to seal it with JB weld then primed and painted it.

Had to adjust the seat positioning because it was too tight to the tank. That took a lot longer than hoped, the rivnut style fittings on the base were loose so instead of the bolts turning out of them the whole fitting would just rotate, took a very long time and a lot of swearing to get it removed, glued them in so hopefully never have this problem again.

Failed MOT on rear indicators and lack of rear reflector. So added a neat one

Wiring to rear indicators was a mess. All I did was unwrap some electrical tape, around the outside of this bunch, the wires were not wrapped individually so several different wires were touching each other. Whoever did this should never do anything electrical or mechanical ever again. So so many issues on this bike in literally every area.

I like to think I did a better job though I am still improving my wiring skills.

I added new LED indicators into the frame ends, you cannot tell they are there until they are on, should be much safer now as they are super bright,





You can make them out in this photo, but they are very neat

Ready for first ride after MOT

On first ride

 

[andy9eleven]

That looks amazing. Superb work.

 

[EF Ian]

Not having anything to alert you to the indictors being on or when it was in neutral did my head in after a short while so I wired in LEDs for the aforementioned as well as one for low oil pressure.

Used my Racelogic VBox to set the speedo so its pretty acurate.

My rear shock was leaking and had pretty much no rebound so I changed it with a nice YSS unit. Felt like a new bike afterwards, so much nice to ride.

Did 1500 miles on it before heading back to work and loved every one of them


Plenty of work to be done on this in winter.

 

[Nickyyy]

That looks so cool very jealous

 

[RevT]

I saw this sitting in that spot on Port promenade about a month ago, really cool wee bike, I love it. You need to get a helmet and gear to suit though, thon helmet looks out of place.

 

[Chris tii]

Your bike makes me want to get my bike test. I would love a k100 cafe racer in Bristol Grey to match my 2002tii.