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Nitty question about the R90S

johnbillerbeck

New member
I am looking at a 1974 R90S to purchase and have the following question. I think I have read that the '74 models had a white ring around the perimeter of the speedo and tach gauges which the the '75 and '76 models did not have. And I have seen this feature in some photographs. The '74 that I am looking at does not have the white rings and I am wondering if perhaps this feature was dropped in later '74 production runs? The bike I am looking at was built in June of 1974 (chassis and engine number 4950604) and looks authentic based on other features. I notice from the http://bmbikes.co.uk/chassispages/enginechassis900.htm and https://www.topspeed.com/motorcycles/motorcycle-reviews/bmw/1973-1976-bmw-r90s-ar28833.html websites that June 1974 marked the end of the 1974 R90S production run and the beginning of the 1975 R90S production run, so it wouldn't be beyond belief if some late 1974 bikes got the gauges without the white ring (if there's even any truth to white ring story anyway). Thanks in advance for any knowledge of this.
 
Welcome to the forum, John! I've vaguely heard of something like what you're describing, but can't seem to find anything very specific. First, do you know if the speedometer is original to the bike? The speedometer will have a small number W=??? and it goes with a matching final drive ratio. Snowbum has a page on his website that gives the W numbers versus the final drive ratios.

http://bmwmotorcycletech.info/technical-articles-list.htm

As for what I can find, I have two books which seem to agree on one point. I have Schwietzer's book on the twin shock models as well as Ian Falloon's book on the boxer series. They indicate that for the '74 models, the tick marks for the speeds (as well as the graduations on the tach) are somewhat fat or thick. Then according to Ian's book, in 1975 (model year or calendar year...dunno) a new MotoMeter speedometer and tachometer were fitted as supplies of the earlier ran out. The new instruments had smaller thinner graduations of the marks and it says "no aluminum ring" whatever that means. One picture in the Schwietzer book has a picture of the early /6 instruments and there does seem to be a lighter ring around the edge but I can't tell if it's a white painted ring on the dial or if it's the aluminum referred to above.
 
Hi Kurt. I saw the bike earlier today and met the current owner. He is the second owner and said he bought the bike with only 4K miles on it from the original owner back in the early nineties. It only has 13K miles showing today, so either it is a really low mileage bike or the speedo was replaced at some point (or it rolled over). But that is what I am trying to figure out. The top picture is a picture of the instrument cluster on the '74 that I am looking at. I used the term 'white ring' in my original post but that could well be the same thing as the aluminum ring that you referred to. The major ticks on both the speedo and tach are fat as you mentioned but no aluminum ring. The other picture I attached is an instrument cluster from a 1976 R90S for comparison (skinny ticks). The speedo does have the W=??? lettering that you mentioned, but I can't read it in the photo and I didn't notice it when I looked at the bike. So it appears to be an early model instrument cluster based on the fat ticks, just not with the rings. Thanks much for the info.
 

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speedo and tach

Instruments on your 1974 R90S look exactly like my 1974 R90/6. And if you pulled off the rubber shades off of your tach and speedo, you would find the metal ring on the outside of your instruments.
 
R90s rings

FWIW, The white ring instrument cluster simply isn't available. My '74 R90s had them when I bought it back in 1980. Being a dumb kid, one day I decided to clean the insides of the glass and figured they just popped off of the plastic cluster. Craaaaaackkkk! Broke the glass and cluster so I bought a new one which of course didn't have the rings.

A few years ago it sort of bugged me so I reached out to a buddy who's in the vinyl graphics business and we made a set of stick on rings. They go on the outside (unlike the original's, which are inside), but from more than 6" away they look totally original.

And congrats on the bike.

RPGR90s
 
white rings

So I should assume that at some point in the past at least the housing was replaced?

two possibilities as I see it:

its a late 74 model and changeover to 75 could have occurred, therefore installing the new cluster
it does have the stock cluster but the white material is gone, which in most cases would leave some of the residue
A third possibility is of course, someone replaced it
 
Thanx for posting this. I picked up a questionable condition 90S thirty-one years ago and always wondered how bad PO nicked me. So just went out to see if I had an old speedo/tach. For the mileage. Yep, I got an aluminum ring under the rubber. Fat markings, and a 1.112 ratio. Originally mileage was 36k. Number 4071xxx. Mfrd. 11/73. Fairing was gone, rear wheel from a '77, both exhaust lifters were busted, lifter bores were damaged, and and and and. Right side of rear axel had been beaten on which may explain a different rear hub. Pays yer money,(1500) takes yer chances. Thanx again. Never really looked at speedo, even after all these years. Like a Timex, takes a lickin, keeps on tickin.
 
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The ring appears to be aluminum pressed onto housing. The aluminum appears a retaining ring for the glass. Rubber hood removed. This is on 407XXXX, 11/73.
 

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I've attached a couple of pictures from Falloons book on the R90S in which he shows and describes the white ring around the inside instrument glass. It's a decal that was affixed to the underside of the glass. He states, "Some early R90S's were inadvertently fitted with an R90/6 speedometer, designed for the lower final drive ratio, resulting in optimistic speedometer and odometer readings." Imagine having one of those! Back when R90S's were produced, BMW always worked at depleting their parts inventory from year to year before moving to new parts for the next model year. Hence there were always questions about when they officially stopped putting specific model year parts on specific bikes. It's a very grey area. They even started using /7 parts on '76 R90S's which is why some have black flush mounted gas caps and black grab handles and black rear fenders etc. I believe it's very possible to have a glass bezel from a '75 on a '74 bike and still call it original to '74. The bike you describe suggests 13K miles and the one picture you show of the instrument area looks like a very nice example. I'd like to see more pictures!;) I would be very surprised if the glass was tampered with or changed.

Falloon R90S.jpginstrument cluser1 r90s.jpg
 
I've attached a couple of pictures from Falloons book on the R90S in which he shows and describes the white ring around the inside instrument glass. It's a decal that was affixed to the underside of the glass. He states, "Some early R90S's were inadvertently fitted with an R90/6 speedometer, designed for the lower final drive ratio, resulting in optimistic speedometer and odometer readings." Imagine having one of those! Back when R90S's were produced, BMW always worked at depleting their parts inventory from year to year before moving to new parts for the next model year. Hence there were always questions about when they officially stopped putting specific model year parts on specific bikes. It's a very grey area. They even started using /7 parts on '76 R90S's which is why some have black flush mounted gas caps and black grab handles and black rear fenders etc. I believe it's very possible to have a glass bezel from a '75 on a '74 bike and still call it original to '74. The bike you describe suggests 13K miles and the one picture you show of the instrument area looks like a very nice example. I'd like to see more pictures!;) I would be very surprised if the glass was tampered with or changed.

View attachment 71911View attachment 71912

My old R90S had the metal rings too, and it was an early 74. I found some photos showing the instruments.
 
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