R80/7 1978 Long or Short Wheelbase

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jackonz
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Joined: Sat Oct 30, 2021 5:29 pm

R80/7 1978 Long or Short Wheelbase

Post by jackonz »

Am getting all the back end of the bike assembled and was looking in the Clymer manual for the quantity of oil to put in the drive shaft tube, the manual had 2 different quantities of oil and this depends if the bike is the short or long wheelbase model, seems that in 1978 they made bothe variants.
So am assuming it must depend on the length of the swing arm, has anyone out there got any info on swing arm measurements so I can get this right.

Thanks :D
Phil J

Nelson NZ.
Kurt in S.A.
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Re: R80/7 1978 Long or Short Wheelbase

Post by Kurt in S.A. »

By the time of 1978, they were all long wheel base. It was mid-way in the 1973 models that it went from SWB to LWB.

As for swing arm, I think it calls for 150cc, but even 100cc would be fine. The fluid just rolls back and forth with brakes and acceleration to lube the u-joint in front and the splines in the back.

Kurt in S.A.
Rob Frankham
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Re: R80/7 1978 Long or Short Wheelbase

Post by Rob Frankham »

If it's `78, it's long wheelbase. The correct quantity according to the book is 150cc.

Rob
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SteveD
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Re: R80/7 1978 Long or Short Wheelbase

Post by SteveD »

Kurt in S.A. wrote: Sat Feb 12, 2022 5:23 pm By the time of 1978, they were all long wheel base. It was mid-way in the 1973 models that it went from SWB to LWB.

As for swing arm, I think it calls for 150cc, but even 100cc would be fine. The fluid just rolls back and forth with brakes and acceleration to lube the u-joint in front and the splines in the back.

Kurt in S.A.
Yes, some is good, too much? likely less good. Less than 150 but don't worry too much. If you know you've added 150 at a change but next time only 75 comes out, then you might want to know where it goes.

A trick when adding the oil to the empty shaft...slowly pour the oil in the filler hole whilst squeezing the bellows at the front of the shaft. It'll add some suction ... idea from Duane Ausherman.
Cheers, Steve
Victoria, S.E.Oz.


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jackonz
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Re: R80/7 1978 Long or Short Wheelbase

Post by jackonz »

Once again thank you all, seems I was given a bum steer (read bad info) from a chap I met here in NZ last year, he has a very nice R75/6 as I recall and we were speaking and when I told him what I had he said "poor you", he was very critical of my bike saying it was no longer a real BMW, he bemoaned how my bike had 5 gears and no kick start and told me to be careful as they changed the swingarm in my model year and it may steer like a pig.

To say I was unimpressed with his attitude after I complimented him on the condition his machine was putting it mildly as it was really nice and I told him so, so I will avoid this bloke in future.

Thank you all.
Phil J

Nelson NZ.
Rob Frankham
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Re: R80/7 1978 Long or Short Wheelbase

Post by Rob Frankham »

You get people like that... There's a lot of bad information out there and it's worth remembering that most of what you hear is someones 'take' on what they, in turn have heard. It pays to treat everything you hear from anecdotal sources (and I include myself and everyone else in that) with a large pinch of salt until you can come up with corroboration... and even then you need to be wary. The 'best' sources are BMW doumentation, followed by the recognised manuals.

Rob
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