Boxerworks.com

Rob Frankham wrote: ↑Tue May 21, 2019 5:45 am ***Health warning*** All of the above assumes that the bike is a stock machine with no modifications to electrics or switchgear.

Rob

Thanks Rob!

Copied this post also to my BMW_Notes.txt file.

Barry send me the Riders handbook .pdf so I think I'm good to go on all 3.

The 3rd bike turns out to be and '83 R80RT.

Steve

One last question ...

What grade of Gas should be used in these 3? Is premium required or is regular OK?

1979 R65, 1983 R80, 1984 R80

Thank you!

For the R65, enter the 7-digit VIN into this to find out more information:

http://www.bmw-z1.com/VIN/VINdecode-e.cgi

It's probably just a plain R65 but it appears that it would have 9.2 compression ratio. If it where me, I'd run premium in the bike.

As for the R80s, they're probably lower compress like 8.2 so probably the lowest grade gas would be fine.

Kurt in S.A.

Kurt in S.A. wrote: ↑Tue May 21, 2019 12:13 pm For the R65, enter the 7-digit VIN into this to find out more information:

http://www.bmw-z1.com/VIN/VINdecode-e.cgi

It's probably just a plain R65 but it appears that it would have 9.2 compression ratio. If it where me, I'd run premium in the bike.

As for the R80s, they're probably lower compress like 8.2 so probably the lowest grade gas would be fine.

Kurt in S.A.

Thanks Kurt. Cool site but no info on Compression Ratio, however this site
http://www-cdr.stanford.edu/~petrie/bmw ... gines.html

shows it as 9.2 : 1

The compression ratio for your 79 R65 is listed in the riders handbook as 9.2:1

Thanks Barry. Good to know.

I have a BMW Riders Handbook applicable to the '83 R80RT but, unfortunately only in the original paper. I'll try to scan it to PDF over the next few days but it runs to over 100 pages so it may take a while. I'll let you know how I get on...

The '83 R80RT and the '84 R80RT should be pretty well identical... unless the '84 was built after October (i.e. a '85 year bike) in which case it'll be very different. It's easy enough to tell. A '85 year bike will have a single sided rear swing arm and totally different wheels.

As it happens, I also have the Riders handbook applicable to a '85 R80RT but that's a different page size and even more pages so it will take twice as long to scan... if the '84 bike turns out to be an '85 year model, let me know and I'll see what I can do.

Rob

Hi,
Further to my last I have scanned the R80RT Rider Handbook... didn't take as long as I expected. Send me a private message with your email address and I'll forward it to you.

Rob

Rob Frankham wrote: ↑Tue May 21, 2019 4:13 pm Hi,
Further to my last I have scanned the R80RT Rider Handbook... didn't take as long as I expected. Send me a private message with your email address and I'll forward it to you.
Rob

Thank you!

After decoding the VINs I have build dates:

1983 R80RT (March, 1983)
1984 R80RT (Aug. 1983)


PM Sent.

Steve

Rob Frankham wrote: ↑Tue May 21, 2019 4:13 pm Hi,
Further to my last I have scanned the R80RT Rider Handbook... didn't take as long as I expected. Send me a private message with your email address and I'll forward it to you.

Rob

Randy aka dwerbil has it online Rob. https://pbase.com/dwerbil/r80rt