1977 R100RS (euro)

[sdpc2]

this is SOOOO true

i had the exact thing happen to me...

How true!

If one begins an Airhead project with the idea of making money or recouping their investment, the owner had better be very knowledgeable and handy, because resale prices are about 2/3 of the restoration costs at absolute best and frequently below 50%.

I know that when I was building my /6 hot rod, I was bleeding cash for a while and in the end shelled a pile of $$$. I mentally added up all the bills and came up with about $8K before I quit counting. I've never told my SO ("Significant Other") how much the bike actually cost, though I think she has a pretty good idea!

Once you get into one of these projects, the bills accumulate very, very quickly and you won't want to do things half way. In most cases, 2K or more for paint and pinstripes, a transmission rebuild by a known shop can/will cost another 1K, $800 for a complete first class head rebuild, $1,500+ for new jugs and pistons, etc, etc, not including the hundreds of hours that you'll spend in the shop, chasing down parts and on the computer.

Funny thing... Once my bike was finished and on the road, I was contacted by two different guys who own beautiful, mint condition R100S bikes that weren't for sale when I began my project but are are now seriously on the market. I coulda saved a mint and almost three years work! Oh well...

In the end the important thing isn't the cost or length of the project but to end up with the bike you really want, cause if you shell out for a resto, you're going to have to keep it!

 

[Gravity]

I haven't restored a vehicle but my brother has. He tells me that it is best to NOT count the cost of stuff otherwise you'll either quit or get a bit angry.

We don't do it for the resale obviously. At least some of us don't.

Great thread,

Gravity

 

[mymindsok]

i had the exact thing happen to me...

Yeah... It's happened to a lot of people.

The saving grace for me was that I accumulated my parts by buying cheap but well selected parts bikes, keeping the best parts and selling off the rest. By the time all was said and done the costs were pretty much a wash and winning my court case against my mechanic sealed the deal.

OTOH, nothings going to cover my time but I still ended up with the bike I wanted and I have the satisfaction of having bring a rather arduous project to a successful completion.

That counts for a lot!

 

[bmweuro]

I see some talk about 38,mm exhaust vs. 40mm on 77 and 78 RS's. For the USA market BMW had to produce a model with quieter exhaust do to new laws on exhaust noise so they produced the CFO model. CFO = California, Florida and Oregon. All of the bikes with this stamped next to the engine number had 38mm exhaust. There was no regulation on where these bikes were sold in the US.

 

[CANUCK66]

VIN: 6180534

this one has no CFO marking next to the engine number

the carbs are marked 94/40/106 so I assume they are 40mm

not sure where on the exhaust to measure to see if 40mm, the pipes don't
seem to have any part number on them that I can see either

however, Jack Hawley says the big piper exhaust clamps are stamped 42 for 42 mm OD, and these ARE

I see some talk about 38,mm exhaust vs. 40mm on 77 and 78 RS's. For the USA market BMW had to produce a model with quieter exhaust do to new laws on exhaust noise so they produced the CFO model. CFO = California, Florida and Oregon. All of the bikes with this stamped next to the engine number had 38mm exhaust. There was no regulation on where these bikes were sold in the US.

 

[bikerfish1100]

if you look at the exhaust port/pipe connection, on a 38mm pipe there is a bit of space between the pipe/sleeve. on the 40 mm there is barely any space at all. unfortuantely, until you've seen both, possibly moments apart, you would not likely realize the difference. "yeah, the bigger one"- but without a "smaller" to compare to.... ???

 

[CANUCK66]

the gap you speak of varies from about....

1.0 mm to almost nothing

.....so, who wants to weigh in? I've seen guys on this forum and others with serial numbers in the 400s and production dates in the 11/76 range call their bikes legit big pipers....this one is 12/76 and a 534 serial number, it seems to have all the indicators as noted above and lacks the CFO stamp

Big Piper or not? what say you?

 

[bikerfish1100]

the carbs are marked 94/40/106 so I assume they are 40mm

all R100s of that early vintage came with 40mm carbs, except for the std /7 version, which had 32s. so that tells ya nothing.
exhaust clamp stamping? (the one in front of the pegs)

 

[CANUCK66]

can't see anything stamped....

...on the front clamps (one has a crash scuff which may have obscured it) but the undamaged one shows nothing obvious on the outward or underside, the rear clamps, however (the ones that attach the mufflers) are clearly stamped 42

 

[bikerfish1100]

sounds like you've got a 40mm version.

 

[Na Cl K9]

1.0 mm to almost nothing

.....so, who wants to weigh in? I've seen guys on this forum and others with serial numbers in the 400s and production dates in the 11/76 range call their bikes legit big pipers....this one is 12/76 and a 534 serial number, it seems to have all the indicators as noted above and lacks the CFO stamp

Big Piper or not? what say you?

The number 42 stamped on the clamps (there is an L and R on the forward clamps as well) would be evidence for a 40mm pipe bike. I have two 77RS made perhaps within a week of each other and shortly before yours in November of 1976 and both are 40mm pipe bikes - measured to be sure. Measure yours to be sure. I do not know when the last 40mm bikes came to the US. I remember the first and second year of the RS very well but only that there were articles on the large pipe bike and why it went away but I do not recall the details. As one post suggested, look at the exhaust nut where it surrounds the exhaust pipe. On a 38mm header bike there will be a noticeable gap between the id of the cast nut and the od of the steel exhaust pipe ÔÇô little if any gap noticeable on a 40mm bike.

The exhaust on RS77 US0370 11/76 40mm

 

[toooldtocare]

My bike came with 38mm version, but San Jose modified it to 40mm exhaust in 1985. The clamps on the pipes also say 42mm.

If in doubt, I would just measure it.

 

[CANUCK66]

measured...

the pipes next to the clamps measure exactly 40 MM OD

 

[Na Cl K9]

Congratulations Sir -

the pipes next to the clamps measure exactly 40 MM OD

You are today's first official lucky winner~! Fascinating isnÔÇÖt it... (-: