BMW r 90 s Restoration

[knucklemoto]

This looks great... one of the absolute classic bikes... Please keep us updated and don't be shy with the photos... If you encounter any problems or discrepancies with the painting I would (strongly!) suggest holding off until the bike is ready in terms of mechanics / electrics / metal work / ergos / chrome work and presenting the whole lot to Chris here on the site for the highest quality paint job - Tunneruk is his monicker...

Keep going sir... great work so far.

 

[byron]

Couple of update photographs on various aspects of the bike The exhaust pipes took a lot of trouble to get off approximately 1 1/2 hours on each side. The routine was heat, WD-40 tap with a hammer reheat and carry on in that vane. It looks as though they both came out with no damage and the pipes are good as well. Presumably they have to be replaced with copper slip and it was very clear that exhaust clamps had no copper on them at all!!!!
The other photo show the front forks with the wheels removed and the triple clamps being undone. As you can see there is a bit of damage inside so a fork repair Kit has been ordered from motor works and two new springs. This will be a first as I have never replaced rebuilt forks but it all seems fairly straightforward I think!!

 

[byron]

Brazed repair

Here are a few photos of the back of the frame, when all the bits were stripped off .It was clear that the right-hand rear web near the swinging arm mount had a crack in it. I tried to weld it twice but each time on cooling there was a ting and it had recracked. So in the end discretion was the better part of valour and I decided to make a small insert in sheet steel and brace it on the top and just to balance up do the same on the left-hand side as well. Hopefully these are blending in when powder coated

 

[byron]

Wiring Removal

Just to keep you updated a few weeks ago I also stripped all the wiring from the bike. As you can see it's a real rats nest inside the headlight and took a while to disconnect, however I ended up making a two-page diagram and using 40 odd tie on labels. I ended up copying the illustrations of the wiring board for aBMW r90s Forum for making my own labelled diagram. The photograph shows one of two pages of diagrams. Hopefully I be able to put all back together again!!! However before that I intend to strip off all the covering and put on new shrink film over all the main wiring parts and perhaps fit new connectors where appropriate and above all test all the wires for continuity to make sure they work fine. Oh I just remembered it's going to be fun refitting the rear lighting through the rear subframe as well it seems to be a real tight squeeze

 

[markjackson]

The "loom in the house, getting marked up with tape" photo looks very familiar. That could have been my kitchen table in December

I re-installed my R90S loom over Christmas and spent last weekend helping find faults on a friend's airhead, then spent sunday re-commissioning a 68 Bonnie's wiring.

What is staggering is that two bikes built so few years apart had wiring looms of such massively different complexity. The BMWs must have at least 4 times as much wire as the triumph, plus interlocks, diodes, neutral switches, clutch switches and the clock. A 90S must have seemed so electrically sophisticated in 1974!

The most complex thing on the Bonnie is the infuriating random mix of metric/AF/Whitworth/gasboard and cycle threads, after I've got used to the all-metric beemers.

And… The headlamp rat's nest on an old airhead may be challenging, but at least they don't have emissions solenoids, ABS and Traction Control!

 

[byron]

A little bit more work done !

Here are a few photos of the shock absorbers clean painted and reassembled. Before disassembly the shock absorbers worked well just looked poor, and now they have black gloss painted bodies rather than the rusty chrome previous. The assembly using the Byron patent sash cramp and Plywood disc make allowed easy reassembly

I have also refitted the drive shaft into the swinging arm today, and as you can see from the photos the jig used worked really really well gripping the inner universal joint and avoiding putting any load on the complete UJ assembly. The torque wrench was set to 150 ft lbs and then a bit more – bloody tight. At least it's done now and I can move on a phew

 

[markjackson]

Good jig

And the shocks look good in black too. I promise to to tell any concours judges about your black shocks if you don't mention my (incorrectly) chromed horn or polished callipers.

 

[steve in nz]

heap of old shitters go for a weekend ride in NZ.

pics of getting to location in NZ. From Christchurch Sth island to Taupo North Island.

https://www.flickr.com/photos/geckoracing/sets/72157649326369953/

 

[byron]

A few bits going together

I have had a couple of days off so started to assembly a few bits to the frame.
This is my first time with swinging arm bearings and I am finding out the hard way.
The frozen outer shells were pushed on to the warmed swinging arm ok with the help of a aluminium drift.
The bearing grease seal proved a little more problematic as I naively thought that freeze it and it will slip on-no way for me
After some unsuccessful attempts with a hide mallet I came up with the sash clamp idea and it worked a treat. Those seals are a tight fit.
As usual when you have the mechanical brain the size of a peanut things take longer to resolve.

 

[byron]

Next bit

So I have also managed to fit the swinging arm into the frame as per the Clymer manual. In fact setting up the spacing and the bearing preload was quite easy and all that lovely Castrol grease mmm

 

[byron]

Final drive on

Well the back end is starting to look correct at last. The shocks are now bolted up in place and I thought that I had better cable tie the drive shaft to the battery tray in case it drops off the final drive. Just a thought though I wonder if anyone can tell me why put LM47 on the splines even though it is in an oil bath.
Anyway off on holidays for a week so no progress for a while.

 

[(RIP) Tunneruk]

Delicious !

 

[markjackson]

Wonderful stuff

That final drive looks like new. How did you get it so clean?

 

[byron]

Lower triple clamp

Just could not resist adding the bearings and the lower triple clamp before I go on holiday to Malaga early tomorrow morning.
It went together so easily- great way to leave the project

 

[byron]

Bit of an update

I managed to clean the rear brake light switch and it came out really well. I also found out that it was push to break. Am I right in thinking that the fit through the 2 holes I have in the rubber cover thus holding it in place.
Long brass screws and washers clearly seem a thing from the past.

In the same area I have had to ream out the frame mount for the rear brake pivot, it was very bunged up with powder coating. Anyway 10 mins with a suitable adjustable reamer and a great fit was achieved.

 

[byron]

Few more things are completed.

The steering damper was in good working order just looked very poor so I decided to polish the zinc casting as best I could and spray black the damper cylinder. I also bought a new plated universal joint from Motobins. I am really pleased with the outcome, just need to buy two replacement m5 set screws to finish the job.


Here are also a couple of photos of the centre stand. I have turned two new over size stainless steel bushes and reamed them into the now round stand holes. The stand has had two plates welded to the lower faces to fill the holes and I also made a foot extension as when I used the bike last year I found it very difficult to catch the stand with my boot.
The stand is now attached to the frame .

 

[jonnie comet]

Loving this.....Looks great.....Please keep it coming........