'79 BMW R45 build

regomodo

Active Member
I meant to open this thread back when I got the bike in March but only now i've decided to sort it out.

A little intro. My dad used to use this bike as a courier almost 22years ago. After he left that job it basically sat in a garage under a sheet for 13years until someone torched my dad's car, which spread to the garage and generally made a mess of the dozens of bicycles and 6 motorbikes that were in there.
My Suzuki DR125 came off the worst with most of the rubbers and plastics melting. This BMW had its paint tarnished and scorched a lot of the rubbers.
Fast forward almost 9 years and I decided to take it off my dad's hands. He nicely gave it to me for free.

This is what it looked like first:

BMW R45 by jonno85uk, on Flickr

Stripped down for transport (hard to believe but there are 4 motorbikes back there):

IMG_20120310_163355.jpg by jonno85uk, on Flickr

The heavy lump in my car:

_DSC0002.jpeg by jonno85uk, on Flickr
 
1st thing on the list to do was getting it running. It probably hadn't turned over in 10years. I remember my dad saying a long while back that one of the carbs would overflow until he knocked the float bowl.
So, carb cleaning 1st.

1 carb and a stuck choke:

IMG_20120317_162702b.jpeg by jonno85uk, on Flickr

IMG_20120317_162635b.jpeg by jonno85uk, on Flickr

The left-hand carb had a load of detritus in the bowl and took a lot of effort clean up the blockages.

IMG_20120317_162539b.jpeg by jonno85uk, on Flickr

The righ-hand float adjusting tab was deformed so that was what caused the overflow.

It's 1st run on 20yr old 4star petrol:
http://youtu.be/A9S_4TtUY84
 
The engine was filthy. In the fins bits of burnt wood mixed with ash, tar and oil were lodged. Lots of carb-cleaner, wd40, scotchbrite and elbow-grease was employed.

A midway through pic. No before & after unfortunately.


Engine cleaning by jonno85uk, on Flickr

One of the exhaust nuts was stuck firm. Bent my spanner slightly trying to get the damn thing off even after copious amounts of wd40 and heat. Managed to remove it using a hacksaw blade to cut down to the threads and a cold chisel to free it up.
 
Paint. I know that hammerite chips and powdercoat lasts but my thinking and experience suggests that hammerite is easily touched up. I decided to use smooth black in spray cans. Took about 2.5 (or 3.5) cans. A bit drippy in places (usually on the undersides, so out of view) but a very nice finish nonetheless, much better than brushed hammerite.


IMG_20120504_191759 by jonno85uk, on Flickr


DSC_0008 by jonno85uk, on Flickr


DSC_0007 by jonno85uk, on Flickr


DSC_0009 by jonno85uk, on Flickr


DSC_0010 by jonno85uk, on Flickr


DSC_0011 by jonno85uk, on Flickr

My swingarm painting rig

IMG_20120512_114921 by jonno85uk, on Flickr

IMG_20120512_130955 by jonno85uk, on Flickr
 
Next up were the snowflake wheels. The lacquer had aged quite nastily so it needed to be removed. This was quite fiddily and very time-consuming: paintstripper, scotchbrite, wirewool, sandpaper and wirebrushes were all used. In the end I couldn't get it all removed on the rear rim and hoped as long as it was clean and the surface was keyed, the etch primer would take care of the rest.

Front wheel prepped:

IMG_20120526_143041.jpg by jonno85uk, on Flickr

Alu etch primed wheels

IMG_20120526_150121.jpg by jonno85uk, on Flickr

IMG_20120526_193913.jpg by jonno85uk, on Flickr

Halfords gloss black and clear lacquer shod with Avon Roadriders:

IMG_20120710_184740.jpg by jonno85uk, on Flickr

img_0001 by jonno85uk, on Flickr

IMG_20120710_182818.jpg by jonno85uk, on Flickr

img_0001_01 by jonno85uk, on Flickr

I had problems with these tyres with the bead not sitting correctly. Turned out they needed inflating to ~80psi to sit. They look awesome on these rims and the rest of the bike.
 
Assorted bits of alu to clean andpolish next. All of it was heavily corroded.
The bevel-gear case:

IMG_20120506_151232 by jonno85uk, on Flickr

IMG_20120506_151245 by jonno85uk, on Flickr
Looks a lot better IRL

IMG_20120522_192225.jpg by jonno85uk, on Flickr

Bits of engine casing:

IMG_20120624_171340.jpg by jonno85uk, on Flickr

IMG_20120624_171332.jpg by jonno85uk, on Flickr
Also polished the air filter and electrics casings.

Not alu. Took the angle-grinder with sand paper wheel and dremel to this cast steel brake-arm.

Brake lever by jonno85uk, on Flickr
 
Good to see another BMW getting the treatment.

Are you UK based? I spotted a Halfords tool box :)

Motobins and Motoworks are good for parts, both used and new - they are nothing to do with me, but I've used them both for parts for my own BMW build and they're good.

There's South Coast boxers on eBay too, but he's pretty ignorant and doesn't reply to emails if he doesn't have the parts to hand, which is a shame as he seems reasonably priced - but I can't be doing with people like that haha
 
It's at about this point I receive notice to vacate the property so I had to get the bike rolling soon.

Assembly time:

IMG_20120530_172242 by jonno85uk, on Flickr
It was actually a whole lot easier to mount the engine from the left

IMG_20120530_174617 by jonno85uk, on Flickr

IMG_20120530_181301 by jonno85uk, on Flickr

IMG_20120530_181319 by jonno85uk, on Flickr

IMG_20120530_201922 by jonno85uk, on Flickr

IMG_20120531_194315 by jonno85uk, on Flickr

IMG_20120531_194346 by jonno85uk, on Flickr

IMG_20120602_162323 by jonno85uk, on Flickr

IMG_20120602_162406 by jonno85uk, on Flickr

Getting the shaft boot on was an absolute nightmare. I found the best way, without destroying your fingers, was to coat the thing in oil and grab it with a cloth and wrestle it into position.
 
TwinPlug said:
Good to see another BMW getting the treatment.

Are you UK based? I spotted a Halfords tool box :)

Motobins and Motoworks are good for parts, both used and new - they are nothing to do with me, but I've used them both for parts for my own BMW build and they're good.

There's South Coast boxers on eBay too, but he's pretty ignorant and doesn't reply to emails if he doesn't have the parts to hand, which is a shame as he seems reasonably priced - but I can't be doing with people like that haha

Cheers
Yep. I got the box on -33% as it was a display model and had a ding to the bottom. So what!

I've used both of those guys. Motoworks were really helpful in sorting out a balance pipe for me as motobins had none and ebay turned up nothing. I used the ebayer to get a front brake master cylinder, had no issues there.
 
The tank. Initially I was going to paint it smooth black but as I sanded it down I really liked the raw look. It's not finished yet but I intend on getting it reasonably polished and lacquer it.

Nitromors only got me so far:

IMG_20120602_180233 by jonno85uk, on Flickr
With hindsight, maybe 60grit wasn't the best idea.

IMG_20120603_124540 by jonno85uk, on Flickr


IMG_20120613_190004.jpg by jonno85uk, on Flickr

IMG_20120613_185942.jpg by jonno85uk, on Flickr

Removing the paint by jonno85uk, on Flickr
 
Now for the seat. I intended for the hump to match the contours of the tank; that didn't happen. In the end it's a bit of a rush job and doing it all by eye as i'm moving again soon and won't likely be allowed to make a mess of the garage this lot is moving to.

I glued mutliple sheets of carboard together, roughed out the shape with some sharp knives and used filler to tidy up.

IMG_20120817_183757 by jonno85uk, on Flickr

Seat hump rough cut by jonno85uk, on Flickr

P38 time! by jonno85uk, on Flickr

img_0001_04 by jonno85uk, on Flickr

img_0001_03 by jonno85uk, on Flickr


For the seat pan I used more carboard and copious amounts of parcel tape, shiney side up.

Roughing out seat hump by jonno85uk, on Flickr

img_0001_05 by jonno85uk, on Flickr

Completed hump by jonno85uk, on Flickr

Rear view by jonno85uk, on Flickr
 
Seat layup with glasssfiber. For the pan I used 4 layers of woven mat and epoxy. The hump was mostly chopped strand and polyester. I taped the edges to the rails (shiny side facing the resin) to get a snug fit. To ensure things came a part nicely (apart from the hump which had angles less than 90deg) I used a lot of turtle wax.

Layup by jonno85uk, on Flickr
Getting rid of all that carboard was a nightmare and took around 3hours yesterday.

Seat removed by jonno85uk, on Flickr

Trimmed up a little to check fit

Seat rear view by jonno85uk, on Flickr

Seat done by jonno85uk, on Flickr

The edges have been straightened and tidied up, mounting holes made and coated with gel coat so I can sand it smooth. It might need some reinforcement on the hump for the light to attach to.
 
A bit out of order here as this came before the seat. The front brake needed sorting, the original master cylinder was shot and I bought the wrong right-hand control (single pull instead of dual). This meant renovating the old control and fitting the new cylinder.

Etch primed and gloss black

Repainted brake lever by jonno85uk, on Flickr
Mounted cylinder, control and cables.

img_0001_05 by jonno85uk, on Flickr
A new stainless braided hose made to order by flexolite.co.uk (£24).

Braided Hose by jonno85uk, on Flickr

The bike originally used the brass anchor splitter for switching on the brake lights. I've got nowhere to mount that so that's why I got a 1-piece hose made. To get the switching i bought a banjo-bolt switch (M10x1.00) which i'm waiting on.

Additionally, I'm not using the original ATE caliper. It was seized. To get it repaired would cost me a lot more than the Brembo I have fitted.
 
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