Finally fitting the carburettors

Well, the carburettors took some time to properly fit. I got the bike running without having them connected to the airbox correctly. But now its time to get them fitting properly so I can get closer to getting the bike MOTed and using it.

The way in which they connect was a little bit of a mystery as the parts diagrams aren’t 100% clear on what bits go in what order. But with a bit of faff and some persuasion, it was made to connect properly.

Firstly I removed the airbox so that I could clean it out properly, also grease the bolts etc. Also refitted the top engine cover before fitting the carbs.

The order in which the airbox, carburettors and engine fit together is an aluminium stepped tube[14] fits into the airbox[3] then a rubber tube[7] (but not shown in the correct place on diagram) fits over the larger end if the ally tube. The other end fits on to the narrower end of the plastic tube[5] the other goes onto the carburettor. The outlet of the carb is connected to the engine with another rubber pipe[7] and a metal threaded adaptor that screws into the head.

I also started to clean the bike now that I have the engine watertight as such. Using some ally wheel cleaner and some ph neutral cleaner (you know the stuff that indicates red on contact with rust). With the use of a stiff wheel cleaning brush, I worked about the rear wheel and hub scrubbing it. Now it looks a lot better, still plenty to clean but it was a start.

Time to make a brake for it.

When I bought the bike I was told that the calliper had been taken off to fix a customer’s bike as it was quicker and easier than rebuilding the old one. But the seller did say he would send me the old calliper in the post. I had made contact but as they were busy it didn’t happen. As his shop is in Crediton ( and my dad was passing nearby he stopped off and had success, he collected the calliper and the right-hand side panel that was also missing. They had it all in a box ready to be sent, just busy and forgot.

The caliper was in need of new pistons and seals, so the kit was ordered. Plus a few more odds and ends.

I cleaned up the callipers as best as I could and had to take off some burrs which I can’t begin to guess how they were caused. I find an easy way to remove the pistons is to push a little air down the calliper using a compressor but only use a small amount. I put the compressor on for only 10 seconds as to avoid too much pressure or the pistons will try to hurt you.

The fitting of the pistons and seals is rather painless and took the time while cleaning to make sure all the fluid holes where clean and free. I also changed the bleed nipples for some tidier ones I had in the shed.

Of course, the next stage was to fit the calliper and bleed the brakes. Which owing to the two nipples for each side it was a breeze to bleed.

Though the two M10 x 60mm Cap head bolts needed to hold the calliper together are in poor condition I wasn’t able to find any replacements in Yellow Zinc like the originals would be. So I have ordered some A4 stainless but I need to think about the tensile strength needed for holding both sides of the calliper together. My plan is to use a G Clamp to hold both side together while I release one bolt and change it.

I will admit that I am tempted to swap out the twin pot calipers for the 4 pots ones from the newer R1100 GS as supposedly with a bit of machining on the mounts they can be made to fit the bike, while keeping the original disk.


Its the weekend and I can spend time doing some work on the bike. So after a little fettling, it was time to fit the carburettor and see if it would fire up.

Its goes Brum

So it starts and though it has a little bit of smoke its not enough to worry about for now as it has been been in a shed with a petrol/oil mix in the engine. We only started it for <1m each time as we wanted to allow oil to move around the system and we were feeding it petrol via a small bottle.

Flush with the success of it starting I popped out and picked up some replacement fuel pipe as the stuff on there is a little ropy. Below are a few pictures of my efforts.

Starter motor woes

So the other weekend I attempted to use the starter and there was just a faint click but no start so I decided to take the starter off and and see if I could spin it up on the bench. Its only a few bolts which are easily annoying to get to in the sense of they can be seen but you need to use a small spanner and make small movements to get the longish bolts undone. But once undone the unit just slides out.

I placed it in the vice and using a spare battery I tried to get it to move but sparks but no life. so I started to disassemble it partially and managed to find this,

This is one of the wires to the earth brush so as I had little else to do I tried to solder it with no luck so found a crimp connector and just made it work. I also greased up a few bits and cleaned and lightly oiled the starter solenoid. Then I put the shaft into the vice and with a bit of oomph I was able to rotate it and I did free it up but it is not brilliant. It would need a full strip and rebuild. But I refitted it to the bike and gave it a test as I just wanted to turn the bike over to get oil into all the right places and it turned over but the starter would stick from time to time but it did enough for me to hear it turn over and to feel puffs from the sparkplug holes.

Valeo D6RA Starter Motor

I went onto the internet and ordered a new replacement starter for ~£50, the BMW specific ones are over £150 but this starter is also fitted to a variety of French cars so are rather cheap. But I also ordered a set of new brushes on the off chance that the cheap starter isn’t the right size etc.

After testing the starter I know the battery would need a top up so I took the moment to fit the NOCO charger lead (not a fan of Optimates). The NOCO lead has a nice feature which is a lower power LED that flashes every few seconds with an indication of charge level.


The New Starter arrived during the week and it only took a few mins to fit,