R90s Special.

Bucephalus

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I’ve just seen this on eBay..Not something I’d be particularly interested in, however, amidst the glowing description of its bespoke specialist build, hand made alloy tank, Grimeca front hub, etc..The Elephant in the room for me is the matter of fact quote engine tilted.?

Now I can’t bang a nail in straight, but wouldn’t think this is a desirable thing to do; taking into account the relationship of the drive shaft, with the output shaft from the gearbox.

I wonder if one of our Egg(Air)heads could enlighten me..:nenau
 

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I thought it was done when suspension travel and swinging arm was lengthened which that doesn't seen to have.
 
I remember watching Helmut Dahne on the IOM and I thought his racebike had its engine tilted like that for increased ground clearance.
Looked up the ad, and hey presto. When we were yoofs, my bro-in-law and I just fitted sidecar springs front and rear and then turned the rocker covers over when they got a bit thin ;)

www.ebay.co.uk/itm/164757120860
 
If you have a look at the Beermat Drawings thread by Mikeyboy, you'll find those engines canted, but somewhat better than the example above.
 
I thought it was done when suspension travel and swinging arm was lengthened which that doesn't seen to have.

Personally in BMW and OC I trust, hence his statement of..Engine tilted for ground clearance, and rear suspension moved to give a more aggressive stance, started to twitch my BS antenna..I would have preferred to put my money into the restoration of the original RTA damaged donor bike.

The tank, exhaust and Grimeca hub, is over 2k before you get into other extensive mods he lists, but each to their own I guess.

Thanks for your shared knowledge guys, always interesting :okay

*Yes Phil I certainly remember a black/white clip of a German BMW racing at the IOM with weird outrigger things that were knee sliders for the rocker covers..:D
 
I built 3 bikes with the motor lifted and tipped,
It’s not as simple as just moving the front mount.
As the gearbox overhangs the rear engine mount if you only lift the front,the rear of the box goes down,leaving insufficient clearance for the prop to enter the swinging arm.
It was a right faff.
The other down side is you cannot remove the oil filter cover as the frame is right in the way .
So an oil change entails unbolting the prop shaft and dropping the front of the motor.
Which adds an hour .
Also,exhausts have to be bespoke.
 
Not just Mike. My R90S has all these mods and a remote oil filter (spin-on) takes seconds. Check this out:
 

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I think if you lifted the back the drive wouldn't line up.

Mike knows.

As Mike says, if you lift the front you have to lift the rear a bit to keep the gearbox to shaft alignment.
 
Yes Phil I found out it was Helmut Dahne at Laurel Bank mid 70’s.

Well I’ve learned it’s possible if done correctly, and this website serves to prove the adage that I don’t know, but I probably know a man that does.

I’ll never forget those sandcast MV’s in Gus Kuhn’s window on the raised plinth, red frames, and suede saddles, aaand shaft drive..Beautiful.

Thanks for the education, oh, and the memories..:thumby:

Oooh (33)..Another beauty, bike that is..:D
 
CB..

You probably knew it better than me, I remember looking at bikes like yours, a bit like looking at a Rock Stars Chick..In appreciation, but not maybe one day, simply unattainable.

I would ride down on a Saturday morning, over Tower Bridge, just to look through the window, pressing my face against the window, and cupping my hands over my eyes for the best view; excited that bikes inside had been moved about.

I wouldn’t dream of entering the shop to browse, I was not worthy, a Pleb like me would be instantly recognised, and I would swiftly shown the door.

I would occasionally see other lads exercising the same Credo, it was never discussed, it was just the way it was..:rob
 
You probably knew it better than me, I remember looking at bikes like yours, a bit like looking at a Rock Stars Chick..In appreciation, but not maybe one day, simply unattainable.

I would ride down on a Saturday morning, over Tower Bridge, just to look through the window, pressing my face against the window, and cupping my hands over my eyes for the best view; excited that bikes inside had been moved about.

I wouldn’t dream of entering the shop to browse, I was not worthy, a Pleb like me would be instantly recognised, and I would swiftly shown the door.

I would occasionally see other lads exercising the same Credo, it was never discussed, it was just the way it was..:rob

I fell in love with it in the window of Reads in Leytonstone (2nd hand) and chopped in my BSA Starfire ... the HP was more than my wages! ...but my old dad ('your not gettin a bike..over my dead body') agreed to stump up the payments in exchange for me working saturday and sunday (and stacking stuff evenings) in our Greengrocers in Ilford.

It was the fastest thing I'd ever been on ...:aidan
 
I remember going to Gus Khuns, drooling at the bikes on display there, Norton, MV and of course BMW. I bought a s/hand black R90s from Anerley motorcycles in 75/6 and used to go to Gus Khuns for bits and service. Many a trip up Stockwell road (or Pride & Clarkes street with its maroon painted buildings) Ah , happy days but nostalgia's not what it used to be:rob. Cheers:beerjug:John B
 
And recently (Castle Combe 7 Apr) spot the difference.
 

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