R90S Meccano Set

SamH · 12-03-2012, 03:27 AM

I picked up a R90S in boxes last week. It looks to have been pulled apart by a fairly meticulous owner. All the boxes are labeled, all the parts look to be there. There'll be bits missing, there always are but all in all it looks good.

Frame, swing arm, stand etc are all powder coated. All the alloy bits have been blasted and are fresh. There's a heap of new parts. 6 pistons, 2 complete new sets (rings, pins, clips still in BMW boxes) and 2 that came from the bike. 4 Barrels, 2 new, 2 original. The chrome all looks to have been redone plus there's a heap of new chrome bits like headlight surrounds etc.
Gearbox has a busted cog but there's a spare one in the box.
The Del's are in good shape and there's rebuild kits and new slides in there.
Wheels are apart, new or re-chromed spokes in paper.
There's a new seat cover in there, gasket kits for the top end, bearing kits and seal kits for just about everything, new and old 90s badges, a new screen, 2 oil pans, new timing chain, new cam, new exhaust nuts... new oil filter. Tons of stuff.

Oh, 2 sets of headers, 2 sets of mufflers and new tank badges. The tanks, fairing, seat base/tail and sidecovers are in good condition but not painted.

The swingarm powdercoat's a bit dodgy, the engine end was taped off but the final drive end wasn't so the splines have powdercoat all over them and the gasket surface too but I guess it'll clean up.

The frame has an odd kink in it, I can't remember if my 90/6 had something similar or not. It might be an issue, I'll post pics and see what people think.

Anyway, I'll be putting it back together, of course. I don't know the history of the bike but the previous owner must have been close to re-assembly. There's a lot of work gone into this big stack of plastic crates. And a lot of rat poo but that's what you get in country sheds.

Here's some pics to start.

How I picked it up

The boxes are all like this. No particular order to any of it. I'm grateful that I had the old R90/6 to learn on so I have, at least, some idea what all this stuff is.

One set of barrels and pistons. There's another set of pistons still in BMW wrappings, an old set that are all caked with carbon and a set of barrels in BMW boxes.

The front wheel, just loosely laced at this point. I'm trying to put bits together as I identify them.

The frame pieced together with zip ties. Final drive just sat there. One of the new Ikons holding everything apart. I cleaned a heap of powdercoat off the bearing seats and installed new head and swingarm bearings.

DoktorT · 12-03-2012, 09:25 AM

Sounds like a dream Airhead project. Please do take lots of pix of the process. Lots of us will be watching and helping with answers.

cas.vanderwoude · 12-03-2012, 09:37 AM

that sounds like a righteous project! I just finished an R90/6 from boxes. It will keep you up nights and plenty of researching on the 'web. I live in Hawaii now but grew up in Devonport. Took my first airhead ride at age 10 in Railton... Never forgot that and its one reason I started this project.

_cy_ · 12-03-2012, 12:53 PM

let me know if you need pic's of any particular item/angle from a 74 R90S.

SamH · 12-16-2012, 01:17 PM

So no pics yet but they're coming.

I've got the swingarm in the frame and the bearings in for the front end. I grabbed the almost new looking final drive out of its box last night and did some investigating. The crown wheel output bearing has been removed. So that's a bit of a pain in the... There's a new one in the box, of course, but I still have to install it.

Any advice? Just follow the manual?

I started getting the fork parts together too. They're definitely in need of a rebuild kit. No bottom buffers, missing rings, etc.

And a question to finish. Who's had experience with stainless fastener kits for airheads? There seem to be a few out there. I've found this one on ebay that seems to be the biggest of the lot.

But this one is specific for the 90s.

And they're just the first couple I looked at. Does anyone have an oppinion?

DoktorT · 12-17-2012, 09:31 AM

[QUOTE=SamH;20263125]So no pics yet but they're coming.

The crown wheel output bearing has been removed. So that's a bit of a pain in the... There's a new one in the box, of course, but I still have to install it.

Any advice? Just follow the manual?

Typically the assembly of the rear drive is not a DIY project. Setting the gear play and the shimming of bearings requires experienced skill or the risk is short term failure. BeemerShop/Ted Porter, Tom Cutter, Craig Hanson or the other known Airhead knowledgable BMW dealers and independant shops know how to do this right the first time.

Who's had experience with stainless fastener kits for airheads?
And they're just the first couple I looked at. Does anyone have an oppinion?

Lot's of people have had problems with stainless fasterners galling. And there are many different grades of stainless. The good grades are quite expensive compared to the grades designed to be cheap. For critical fasteners, no stainless meets the specs of the original steel fasteners.

SamH · 12-17-2012, 10:32 PM

I'm in Aus so a lot of those all knowing bimmer specialists are a bit out of reach. I'll dig around for an aussie airhead tech.

SamH · 12-28-2012, 01:37 AM

Did a bit of work today, love Christmas holidays. Finally tracked down the thrust bearings for the crank. Once I've read over the manual a bit more I'll have a go at putting the crank back in and measuring it up. I have no idea what state the bottom end was in before dissassembly. Sounds like there's not much that goes wrong with them so hopefully it was just pulled out to sandblast the case.

Made a new wedding band for the rear wheel as the one that came with it didn't load up the bearing shells at all. I'm not sure what's going on with the back wheel because it's not going in straight, or rather it goes in and sits kind of skewed against the final drive. I hope I've just left something out and the swing arm isn't bent or something odd.

jackd · 12-28-2012, 06:00 AM

Quote:

Originally Posted by SamH

Sounds like there's not much that goes wrong with them so hopefully it was just pulled out to sandblast the case.

You better figure out what the PO was doing with that block. If he did in fact sand blast it then make sure that he didn't leave any residual blast media in the internal areas - you don't want it destroying your internal components while the bike is in service.

Kai Ju · 12-28-2012, 11:01 AM

Quote:

Originally Posted by jackd

You better figure out what the PO was doing with that block. If he did in fact sand blast it then make sure that he didn't leave any residual blast media in the internal areas - you don't want it destroying your internal components while the bike is in service.

I wouldn't take a chance if there is any evidence of media blasting. I don't think you can get all of it out if it was in fact blasted.
The blast media gets 'peened' into place during the process and may come out when the engine goes through heat cycling. Almost like a time release capsule of engine destruction.

Not to mention lack of access to all of the oil passages and the nooks and crannies you can't see, much less get to to clean.

jackd · 12-28-2012, 11:07 AM

Let's not scare the guy. But you're right.

Kai Ju · 12-28-2012, 11:14 AM

Quote:

Originally Posted by jackd

Let's not scare the guy. But you're right.

I'd rather scare him now than read a post later where he tells us that his engine blew up.......

SamH · 12-28-2012, 01:07 PM

The block's clean as new, same with all the components. The internals weren't blasted of course. There's not a single grain of media anywhere.

I've had an engine soda blasted locally and there was crud left all over it and in it. That's not the case here. It may have just been vapor blasted or steam cleaned.

The rear wheel's missing it's inner top hat spacer too, simple, like I'd hoped.

*edit*

I was putting the rear wheel together today for the 5 or 6th time and when I went to install the outer bearing cover/seal holder there was a heap of grit in the 5 bolt holes so I'll take the sand in the engine comment seriously.
Looks like the swingarm might be bent too. Bummer.

SamH · 12-31-2012, 09:34 PM

Checking the end play on the crank shaft, .11mm.

The two cams that came with the bike. Any idea how I can figure out what's what? I've taken pics of all the identifying marks.

The rear hub/final drive/swingarm issue. If I tighten up the final drive on the swing arm it pulls the whole thing out of alignment. You can just make out the wedge shaped gap between the final drive and the swingarm. It's touching on the outside of the housing but still has a gap on the inside, that's with the hub and final drive together and the axle installed and torqued up.

Either a new swingarm is in order or a jig and lots of pressure.

Kai Ju · 01-01-2013, 12:29 AM

Your swingarm looks bent.
Look at the distance between the muffler /passenger footpeg brackets and the swingarm on the left and right side. There is more distance on the right then on the left indicating that the swingarm is bent inwards.
Also, I just measured the distance between the hub and the swingarm, and on my bike that is 65.68mm, as measured from the top hat spacer to the swingarm.
As far as checking your block for blast media, just run some of the front cover bolts into their holes and see if you get the same gritty feeling that you did on the rear wheel bearing cap.

12-03-2012, 03:27 AM	#1
SamH ^OP 90S on the bench Joined: Aug 2005 Location: Tasmania, Australia Oddometer: 431	R90S Meccano Set - now with pictures! I picked up a R90S in boxes last week. It looks to have been pulled apart by a fairly meticulous owner. All the boxes are labeled, all the parts look to be there. There'll be bits missing, there always are but all in all it looks good. Frame, swing arm, stand etc are all powder coated. All the alloy bits have been blasted and are fresh. There's a heap of new parts. 6 pistons, 2 complete new sets (rings, pins, clips still in BMW boxes) and 2 that came from the bike. 4 Barrels, 2 new, 2 original. The chrome all looks to have been redone plus there's a heap of new chrome bits like headlight surrounds etc. Gearbox has a busted cog but there's a spare one in the box. The Del's are in good shape and there's rebuild kits and new slides in there. Wheels are apart, new or re-chromed spokes in paper. There's a new seat cover in there, gasket kits for the top end, bearing kits and seal kits for just about everything, new and old 90s badges, a new screen, 2 oil pans, new timing chain, new cam, new exhaust nuts... new oil filter. Tons of stuff. Oh, 2 sets of headers, 2 sets of mufflers and new tank badges. The tanks, fairing, seat base/tail and sidecovers are in good condition but not painted. The swingarm powdercoat's a bit dodgy, the engine end was taped off but the final drive end wasn't so the splines have powdercoat all over them and the gasket surface too but I guess it'll clean up. The frame has an odd kink in it, I can't remember if my 90/6 had something similar or not. It might be an issue, I'll post pics and see what people think. Anyway, I'll be putting it back together, of course. I don't know the history of the bike but the previous owner must have been close to re-assembly. There's a lot of work gone into this big stack of plastic crates. And a lot of rat poo but that's what you get in country sheds. Here's some pics to start. How I picked it up The boxes are all like this. No particular order to any of it. I'm grateful that I had the old R90/6 to learn on so I have, at least, some idea what all this stuff is. One set of barrels and pistons. There's another set of pistons still in BMW wrappings, an old set that are all caked with carbon and a set of barrels in BMW boxes. The front wheel, just loosely laced at this point. I'm trying to put bits together as I identify them. The frame pieced together with zip ties. Final drive just sat there. One of the new Ikons holding everything apart. I cleaned a heap of powdercoat off the bearing seats and installed new head and swingarm bearings. SamH screwed with this post 12-26-2012 at 02:33 PM

12-03-2012, 12:53 PM	#4
_cy_ Beastly Adventurer Joined: Sep 2011 Location: Tulsa, Oklahoma Oddometer: 2,725	let me know if you need pic's of any particular item/angle from a 74 R90S. __________________ Bringing BMW R90S back to life, R80G/S, LiFePO4 testing Which is more reliable ... Points or Electronic Ignition for Airheads?

12-16-2012, 01:17 PM	#5
SamH ^OP 90S on the bench Joined: Aug 2005 Location: Tasmania, Australia Oddometer: 431	So no pics yet but they're coming. I've got the swingarm in the frame and the bearings in for the front end. I grabbed the almost new looking final drive out of its box last night and did some investigating. The crown wheel output bearing has been removed. So that's a bit of a pain in the... There's a new one in the box, of course, but I still have to install it. Any advice? Just follow the manual? I started getting the fork parts together too. They're definitely in need of a rebuild kit. No bottom buffers, missing rings, etc. And a question to finish. Who's had experience with stainless fastener kits for airheads? There seem to be a few out there. I've found this one on ebay that seems to be the biggest of the lot. But this one is specific for the 90s. And they're just the first couple I looked at. Does anyone have an oppinion? SamH screwed with this post 12-16-2012 at 03:59 PM

12-28-2012, 01:07 PM	#13
SamH ^OP 90S on the bench Joined: Aug 2005 Location: Tasmania, Australia Oddometer: 431	The block's clean as new, same with all the components. The internals weren't blasted of course. There's not a single grain of media anywhere. I've had an engine soda blasted locally and there was crud left all over it and in it. That's not the case here. It may have just been vapor blasted or steam cleaned. The rear wheel's missing it's inner top hat spacer too, simple, like I'd hoped. edit I was putting the rear wheel together today for the 5 or 6th time and when I went to install the outer bearing cover/seal holder there was a heap of grit in the 5 bolt holes so I'll take the sand in the engine comment seriously. Looks like the swingarm might be bent too. Bummer. SamH screwed with this post 12-29-2012 at 02:29 AM

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12-03-2012, 09:25 AM	#2
DoktorT BigBrowedNeandereer Joined: Apr 2009 Location: Spokaloo Oddometer: 1,009	Sounds like a dream Airhead project. Please do take lots of pix of the process. Lots of us will be watching and helping with answers.

12-03-2012, 09:37 AM	#3
cas.vanderwoude Adventurer Joined: Nov 2012 Location: Hawaii Oddometer: 16	that sounds like a righteous project! I just finished an R90/6 from boxes. It will keep you up nights and plenty of researching on the 'web. I live in Hawaii now but grew up in Devonport. Took my first airhead ride at age 10 in Railton... Never forgot that and its one reason I started this project.

12-17-2012, 09:31 AM	#6
DoktorT BigBrowedNeandereer Joined: Apr 2009 Location: Spokaloo Oddometer: 1,009	[QUOTE=SamH;20263125]So no pics yet but they're coming. The crown wheel output bearing has been removed. So that's a bit of a pain in the... There's a new one in the box, of course, but I still have to install it. Any advice? Just follow the manual? Typically the assembly of the rear drive is not a DIY project. Setting the gear play and the shimming of bearings requires experienced skill or the risk is short term failure. BeemerShop/Ted Porter, Tom Cutter, Craig Hanson or the other known Airhead knowledgable BMW dealers and independant shops know how to do this right the first time. Who's had experience with stainless fastener kits for airheads? And they're just the first couple I looked at. Does anyone have an oppinion? Lot's of people have had problems with stainless fasterners galling. And there are many different grades of stainless. The good grades are quite expensive compared to the grades designed to be cheap. For critical fasteners, no stainless meets the specs of the original steel fasteners.

12-17-2012, 10:32 PM	#7
SamH ^OP 90S on the bench Joined: Aug 2005 Location: Tasmania, Australia Oddometer: 431	I'm in Aus so a lot of those all knowing bimmer specialists are a bit out of reach. I'll dig around for an aussie airhead tech.

12-28-2012, 01:37 AM	#8
SamH ^OP 90S on the bench Joined: Aug 2005 Location: Tasmania, Australia Oddometer: 431	Did a bit of work today, love Christmas holidays. Finally tracked down the thrust bearings for the crank. Once I've read over the manual a bit more I'll have a go at putting the crank back in and measuring it up. I have no idea what state the bottom end was in before dissassembly. Sounds like there's not much that goes wrong with them so hopefully it was just pulled out to sandblast the case. Made a new wedding band for the rear wheel as the one that came with it didn't load up the bearing shells at all. I'm not sure what's going on with the back wheel because it's not going in straight, or rather it goes in and sits kind of skewed against the final drive. I hope I've just left something out and the swing arm isn't bent or something odd.

12-28-2012, 11:07 AM	#11
jackd Beastly Adventurer Joined: Dec 2006 Location: North Cowichan Oddometer: 2,386	Let's not scare the guy. But you're right.

12-31-2012, 09:34 PM	#14
SamH ^OP 90S on the bench Joined: Aug 2005 Location: Tasmania, Australia Oddometer: 431	Checking the end play on the crank shaft, .11mm. The two cams that came with the bike. Any idea how I can figure out what's what? I've taken pics of all the identifying marks. The rear hub/final drive/swingarm issue. If I tighten up the final drive on the swing arm it pulls the whole thing out of alignment. You can just make out the wedge shaped gap between the final drive and the swingarm. It's touching on the outside of the housing but still has a gap on the inside, that's with the hub and final drive together and the axle installed and torqued up. Either a new swingarm is in order or a jig and lots of pressure.

01-01-2013, 12:29 AM	#15
Kai Ju Beastly Adventurer Joined: Jul 2009 Location: So Cal Oddometer: 1,068	Your swingarm looks bent. Look at the distance between the muffler /passenger footpeg brackets and the swingarm on the left and right side. There is more distance on the right then on the left indicating that the swingarm is bent inwards. Also, I just measured the distance between the hub and the swingarm, and on my bike that is 65.68mm, as measured from the top hat spacer to the swingarm. As far as checking your block for blast media, just run some of the front cover bolts into their holes and see if you get the same gritty feeling that you did on the rear wheel bearing cap.