1980 BMW E26 M1
Discussion
fluoxetine said:
Great thread - I was there (Munich) a fortnight ago, and think I stayed in the same hotel
(There was even a Weismann to park next to
)
The car park looks similar, but I don't think it's the same, yours looks bigger and the style of the numbers is slightly different. The hotel we stayed in was the Hotel Europa on Dachauer Straße, about 2 miles from the Olympic Stadium.(There was even a Weismann to park next to
)
I thought 140 was pushing it a bit on the old Magnesium alloys, but it got there so easily. I 'think', but have not experimented to find out, that the engine has had the rev limiter removed, or at least significantly raised as the internals have been very precisely balanced.
The speedo definitely under reads, according to my calculations 140 is pretty much exactly 130mph. Even if the 7,000 rpm limit is in place it should reach an indicated 175mph (actually 162 mph), if the limiter has been raised then I'd be pretty sure it would significantly exceed the maximum of 180mph on the speedo judging by the way it was pulling.
The speedo definitely under reads, according to my calculations 140 is pretty much exactly 130mph. Even if the 7,000 rpm limit is in place it should reach an indicated 175mph (actually 162 mph), if the limiter has been raised then I'd be pretty sure it would significantly exceed the maximum of 180mph on the speedo judging by the way it was pulling.
A little over 2 months after dropping the car off at Munich Legends after the Munich trip, she finally arrived home again this morning.
The main reason for leaving her at Munich Legends was to replace the suspension bushes, basically the 36 year old polyurethane had perished and they were dropping to pieces. This is what they looked like after being taken out of the wishbones
The Polyurethane was about the constancy of a wax crayon!
There are two different bushes used, 12 of one type for the front and upper rear wishbones and 8 of another for the lower rear wishbone. The front/upper rear is still available, so I could use the OEM part. The lower rear bush however is NLA. I say bush, the NLA part is more like a ball joint filled with Polyurethane. Luckily I have the technical drawing and specification of the bush, however no one I approached was willing or able to make an exact replica. Given the axis over which movement can occur, pretty much purely rotation about the axis of the bush, I decided that a simple poly bush was going to be more than adequate and definitely preferable to a deteriorating ball joint. I found a company that would make up custom poly bushes, DuraFlex, and had them manufacture a couple of sets using the highest density Polyurethane available, 90D which is pretty much rock solid!
While the suspension was apart I thought I might as well get the Bilstein shock absorbers refurbished and this is what has taken the time. While waiting I had the wishbones re-painted too, so it all looks nice and new under there now, this is the only picture I have for now, I'll take more when I take the wheels off for cleaning.
If you look closely, you'll notice that the top wishbone mounting point has been moved down. At some point in the past the suspension geometry had been set to give the lowest possible ride height. This proved to be a bit of a pain to live with, every sleeping policeman had to be negotiated with extreme care, to prevent grounding. On the Munich trip, my co-driver coined the phrase "fatty out" every time a speed bump had to be crossed. The geometry has now been set to the lowest within the factory spec range, which has meant raising it by about 20 mm.
A couple of other things were done, again while waiting. A new windscreen was fitted as the original had a small scratch and was just starting to de-laminate. The cooling system was flushed and antifreeze changed. The A/C fan was looked at and adjusted. The door lock connecting rods were lengthened by about 10mm, no idea why they were short but they were, so the pins went a bit too far into the door card when locked.
So, now I just need to remove all the temporary wrap and give her a really good clean!
The main reason for leaving her at Munich Legends was to replace the suspension bushes, basically the 36 year old polyurethane had perished and they were dropping to pieces. This is what they looked like after being taken out of the wishbones
The Polyurethane was about the constancy of a wax crayon!
There are two different bushes used, 12 of one type for the front and upper rear wishbones and 8 of another for the lower rear wishbone. The front/upper rear is still available, so I could use the OEM part. The lower rear bush however is NLA. I say bush, the NLA part is more like a ball joint filled with Polyurethane. Luckily I have the technical drawing and specification of the bush, however no one I approached was willing or able to make an exact replica. Given the axis over which movement can occur, pretty much purely rotation about the axis of the bush, I decided that a simple poly bush was going to be more than adequate and definitely preferable to a deteriorating ball joint. I found a company that would make up custom poly bushes, DuraFlex, and had them manufacture a couple of sets using the highest density Polyurethane available, 90D which is pretty much rock solid!
While the suspension was apart I thought I might as well get the Bilstein shock absorbers refurbished and this is what has taken the time. While waiting I had the wishbones re-painted too, so it all looks nice and new under there now, this is the only picture I have for now, I'll take more when I take the wheels off for cleaning.
If you look closely, you'll notice that the top wishbone mounting point has been moved down. At some point in the past the suspension geometry had been set to give the lowest possible ride height. This proved to be a bit of a pain to live with, every sleeping policeman had to be negotiated with extreme care, to prevent grounding. On the Munich trip, my co-driver coined the phrase "fatty out" every time a speed bump had to be crossed. The geometry has now been set to the lowest within the factory spec range, which has meant raising it by about 20 mm.
A couple of other things were done, again while waiting. A new windscreen was fitted as the original had a small scratch and was just starting to de-laminate. The cooling system was flushed and antifreeze changed. The A/C fan was looked at and adjusted. The door lock connecting rods were lengthened by about 10mm, no idea why they were short but they were, so the pins went a bit too far into the door card when locked.
So, now I just need to remove all the temporary wrap and give her a really good clean!
Not driven it far since the refresh, just about 5 miles to fill up with fuel where I was approached by a guy in a M235i saying he'd never seen one on the road and could he take some pictures. I'd say it feels a bit tighter, but not that much different to be honest. Although the polyurethane in the bushes was shot, I think it's main purpose was to keep dirt out of the joints. I'm sure after a year or so those rear ball joints in particular would be seriously worn. I did have to navigate some speed bumps, no hint of grounding out and far less stressful than it used to be!
Another small job that needed tackling was the rear view mirror.
There were two problems, first the design has a mirror and a piece of glass at a slightly different angle, the reflection from glass being used in dipped mode. This means that there is a gap between the two and over the years the internal surfaces had become dirty just like the driving lights. It's not so bad during the day, but at night with lights behind it creates a lot of glare.
Having spoken to someone while in Munich, they said it was an easy job to take apart and clean. I was a little nervous because the mirror is no longer available, the housing is made from 36 year old plastic that gets baked in the sun and is clipped together and the mirror has always been rather loose on it's swivel mounting. That's the second problem, I've always suspected that there is probably some sort of plastic clamp inside that's cracked, so it still holds it firmly enough so it does not move while driving, but it's just a bit floppy. If I take it to pieces will it just fall apart in my hands!
So I warmed up the housing by placing my trusty fan heater in the car and went about opening it up. Actually the plastic was very flexible and I could take it apart with just my fingers, the outer surround is just held in place with 4 barbed clips. Sure enough, just as anticipated, the clamp for the swivel mount was cracked
So, first question, try to fix it or leave it as is? It looks as though the clamp piece, which is part of the dipping mechanism, is just held in place with 4 clips. Should I un-clip them and risk not being able to put it together again or not? In the end I chickened out! Due to the soft nature of the plastic I think it would be near impossible to mend the cracked piece. I decided to use a more Heath Robinson fix, cable ties!
It's now a little more solid and should not get any worse.
Here are the mirror and covering glass removed from the housing
Both the interior surface of the glass and the mirror were quite grimy, difficult to see in the picture above, but after wiping a small section on the glass and mirror you can see how dirty they were
All put back together again
There were two problems, first the design has a mirror and a piece of glass at a slightly different angle, the reflection from glass being used in dipped mode. This means that there is a gap between the two and over the years the internal surfaces had become dirty just like the driving lights. It's not so bad during the day, but at night with lights behind it creates a lot of glare.
Having spoken to someone while in Munich, they said it was an easy job to take apart and clean. I was a little nervous because the mirror is no longer available, the housing is made from 36 year old plastic that gets baked in the sun and is clipped together and the mirror has always been rather loose on it's swivel mounting. That's the second problem, I've always suspected that there is probably some sort of plastic clamp inside that's cracked, so it still holds it firmly enough so it does not move while driving, but it's just a bit floppy. If I take it to pieces will it just fall apart in my hands!
So I warmed up the housing by placing my trusty fan heater in the car and went about opening it up. Actually the plastic was very flexible and I could take it apart with just my fingers, the outer surround is just held in place with 4 barbed clips. Sure enough, just as anticipated, the clamp for the swivel mount was cracked
So, first question, try to fix it or leave it as is? It looks as though the clamp piece, which is part of the dipping mechanism, is just held in place with 4 clips. Should I un-clip them and risk not being able to put it together again or not? In the end I chickened out! Due to the soft nature of the plastic I think it would be near impossible to mend the cracked piece. I decided to use a more Heath Robinson fix, cable ties!
It's now a little more solid and should not get any worse.
Here are the mirror and covering glass removed from the housing
Both the interior surface of the glass and the mirror were quite grimy, difficult to see in the picture above, but after wiping a small section on the glass and mirror you can see how dirty they were
All put back together again
gforceg said:
Really interesting to read this, as always.
I would have thought the cracked piece would be a perfect candidate for a 3D printed replacement if unavailable elsewhere.
Yes, I would imagine so. That's what I was going to investigate. I think the problem may be the material type, but I'm no expert on 3D printing. The material would have to be strong enough to hold the ball tightly, but flexible enough for the dip toggle at the bottom of the mirror, it's all one piece with a plastic hinge between the main block and the toggle.I would have thought the cracked piece would be a perfect candidate for a 3D printed replacement if unavailable elsewhere.
Small update.
Wheels for the M1 are very hard to come by, Campagnolo stopped making them in the early 80's, probably 1982. They are made of Magnesium and are very difficult to refurbish, if you do it wrong you'll quite probably wreck the wheel. When you do find the wheels they are usually very expensive, there is a set on e-bay in the USA right now for $25,000!
Last year I stumbled across a set for sale that looked to be in pretty poor condition, but as they were relatively cheap I though they were worth a punt, if one came up good then they would be worth the price paid.
The wheels arrived after a week or so, they looked slightly better that I thought they might, one looked quite bad and all had some form of curbing, but the base Magnesium didn't look too bad. The tyres were well past their use by, one of them being made some time in the 1990's.
I'd not seen the insides of the wheels before they arrived, they were dirty but not too bad otherwise.
I got the old tyres off and they looked like this
I did a bit of searching and found a PistonHeads member silvers, Steve from Grind'n'Shine http://www.grindnshine.co.uk/ who seemed to know what he was talking about. So I took the wheels round to him, had a good chat and left him to work on them.
About 4 weeks later I picked them up, wow, what a difference! Not perfect, because there was quite a lot of curb damage and you can't easily build up Magnesium as you can with Aluminium, but they exceeded my expectations given the state they were in before.
The one obvious thing missing was the Campagnolo logo. Some more research and I found a small company called Classic Screen who made up some vinyl stickers, they even had direct access to the correct font so they did not have to scan anything. The stickers turned up very quickly and look perfect.
Here's a side by side of the refurbished wheel and an original finish wheel, pretty darn close!
So I now have a very respectable spare set of genuine wheels.
Wheels for the M1 are very hard to come by, Campagnolo stopped making them in the early 80's, probably 1982. They are made of Magnesium and are very difficult to refurbish, if you do it wrong you'll quite probably wreck the wheel. When you do find the wheels they are usually very expensive, there is a set on e-bay in the USA right now for $25,000!
Last year I stumbled across a set for sale that looked to be in pretty poor condition, but as they were relatively cheap I though they were worth a punt, if one came up good then they would be worth the price paid.
The wheels arrived after a week or so, they looked slightly better that I thought they might, one looked quite bad and all had some form of curbing, but the base Magnesium didn't look too bad. The tyres were well past their use by, one of them being made some time in the 1990's.
I'd not seen the insides of the wheels before they arrived, they were dirty but not too bad otherwise.
I got the old tyres off and they looked like this
I did a bit of searching and found a PistonHeads member silvers, Steve from Grind'n'Shine http://www.grindnshine.co.uk/ who seemed to know what he was talking about. So I took the wheels round to him, had a good chat and left him to work on them.
About 4 weeks later I picked them up, wow, what a difference! Not perfect, because there was quite a lot of curb damage and you can't easily build up Magnesium as you can with Aluminium, but they exceeded my expectations given the state they were in before.
The one obvious thing missing was the Campagnolo logo. Some more research and I found a small company called Classic Screen who made up some vinyl stickers, they even had direct access to the correct font so they did not have to scan anything. The stickers turned up very quickly and look perfect.
Here's a side by side of the refurbished wheel and an original finish wheel, pretty darn close!
So I now have a very respectable spare set of genuine wheels.
Not sure exactly which set I'll keep on the car. The set on the car at the moment are very good with no curbing at all, however when I had the tyres changed there are signs that the lacquer is cracking where the tyre bead meets the rim. So my current plan is to swap the tyres to the refurbished rims, the see if the other set can be partially refurbished just on the insides and rear. Unless it's unavoidable I don't want to remove the OEM finish from the front of the wheels.
Here's the e-bay listing for a used set for $25,000 http://www.ebay.co.uk/itm/182398816354
Here's the e-bay listing for a used set for $25,000 http://www.ebay.co.uk/itm/182398816354
fatboy69 said:
The M1 is a sublime car.
Beautiful to look at & an utter joy to drive - back in the day when I worked for The Patrick Collection we had a white M1 which was registered XOX 1T.
I don't suppose you know which number that car was? XOX 1T is now on a red 1997 Ferrari (might be a 550 given the age and engine capacity).Beautiful to look at & an utter joy to drive - back in the day when I worked for The Patrick Collection we had a white M1 which was registered XOX 1T.
fatboy69 said:
Always hated getting out of the drivers seat.
I know it's pretty low down, but it's not that bad getting out! e21Mark said:
Do magnesium rims degrade with age? I just wondered if they needed regular checking from a safety perspective?
mark.c said:
I wouldn't think any particular routine checks would be required other than a good visual inspection every now and again, happy to learn if this is not the case. In the aircraft industry magnesium alloy is used extensively and is subject to various routine inspections from a visual with the naked eye to more extensive NDT techniques to look for flaws/cracks etc. This various with the type of component, it's make up, and of course it's intended purpose and environment. One thing I will say is that in the right conditions, if not protected, it will corrode for fun, and fast.
Magnesium is indeed rater strange with regard to ageing and corrosion resistance. It will virtually desegregate in days in some environments and be fine in others that you'd expect to cause problems for years.I've been told that the wheels had a shelf life from date of manufacture of just 5 years. If that's true then all my wheels are just 30 years past that!!
I believe that the degradation is rapid to start with and the rate tails off, the current rate of degradation should now be pretty slow, so if they are OK now they should be OK for a bit. The design is also and important aspect, as the M1 wheels don't have isolated spokes, just spokes behind the flat surface, they are pretty strong. The wheels I had refurbished looked to be in very good structural condition with minimal corrosion and pitting. I don't know what the ones on the car are like but I did restrict autobahn speeds in September to 140mph just in case.
The long term plan is to keep the original wheels for show and to get some near replicas made up for road trips so I'm not worrying about damage or disintegration! On the replica front I've found customisable stock design from the USA that's not too expensive. It's a two piece forged Aluminium wheel, you can specify dish, offset, hidden or exposed hardware etc. They are currently nearing completion, and looked like this earlier in the week, the centre still need painting black
Unfortunately the size and number of slots can not easily be changed, so not identical but I think give the same overall effect. The centre has been machined to take the original wheel centre. The cost of a full set being a less than the price of a single poor condition genuine wheel. If the quality of these is good I'm going to see if they can customise the design even more to get a very close replica - 3 thinner slots and a dummy inner painted grove, more solid central section, a small lip around the central piece and a small cutout where the valve is should pretty much do it I think.
e21Mark said:
Rotiform BM1 are a current wheel inspired by these, but unsure how they compare side by side? (These may be the rims you're talking about?)
https://wheelwarehouse.com/products/rotiform-bm1-c...
Yes Mark, those are them. https://wheelwarehouse.com/products/rotiform-bm1-c...
http://www.rotiform.com/bm1-w-24361.htm
They are making them as close as they can, within their standard templates, to the original wheels. You can see from the picture I posted earlier that it's not quite the same as any of the stock pictures.
I have photos of most M1s that have been registered in the UK in one form or another, but that one was actually from e-bay!
http://www.ebay.co.uk/itm/291669659142
Yours for 99p plus £1 p&p!
Just noticed, that car looks like it has the optional rear mud flaps, I've only seen one other car with those on.
http://www.ebay.co.uk/itm/291669659142
Yours for 99p plus £1 p&p!
Just noticed, that car looks like it has the optional rear mud flaps, I've only seen one other car with those on.
Edited by RichardM5 on Thursday 5th January 16:26
e21Mark said:
The first time I saw an M1 was at L&C in Tunbridge Wells, circa 1990/91. It was white, with a thick vertical tri colour stripe up the nose and ending just after. The price was £43 995. I was only in my early 20's and barely had £44 let alone £44 000! I was smitten with the look of the M1 though and the dual roundel on that rear was the icing on the cake for me. It was special without being OTT. 20+ years later and I still feel the same about them. I'm further away than ever from ownership, although my dodgy left leg means I can't get in one anyway! (I tried at Munich Legends where I'd taken the M3 in the hope I might blag a test drive ) It's their look, the history and pedigree and the rarity that does it for me.
Probably this car, which was owned by BMW in the mid 80's. ) It's their look, the history and pedigree and the rarity that does it for me. 
EddyBee said:
Lovely car. Saw it in person at Gaydon back in August. First one I've ever seen in the flesh.
Any more info on the m10 engine below?
It's a formula 2 version of the engine, but what struck us is that although it's a 4 cylinder engine there are 4 inlets and 4 exhaust ports on each side and they are staggered. The only possible head configuration is that each cam drives both a single inlet and single exhaust per cylinder and that the the two inlets and two exhaust ports are diagonally opposite one another. Not a configuration we'd ever seen before.Any more info on the m10 engine below?
RichardM5 said:
Lots of engines, including this intriguing version of the M10 4 cylinder engine
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