how to cross referance parts manual.

schrader7032 · Post by **schrader7032** » Tue Jun 17, 2008 12:27 pm

Steve -

I wish I could help...I don't own an official parts manual, so I don't know how that manual is arranged. I tend to use either on-line parts fiche programs or use a program that I was given called ETK. IIRC, ETK was one of the predecessor BMW parts counter programs. Once it became outdated, it was "pirated" for use by the local community. The ETK does have a feature to help cross reference parts. I've not seen anything like that in any of the on-line sources, though.

BTW...what is the name of the manual that you have? I've heard of the SNABB catalog...

Kurt in S.A.

steve fewster · Post by **steve fewster** » Tue Jun 17, 2008 5:07 pm

Hi Kurt, thanks for your reply, the name of the parts Manual is BMW Motorrad GMBH +Co. it covers BMW`s from the R 50/5 - R 100 RT, at the moment I am looking for a wiring harness for my R100S, I can get my hands onto a 1984 R 100 RT harness, but! will it fit my 1977 R100S? any help in this area would be greatly appreciated.

schrader7032 · Post by **schrader7032** » Tue Jun 17, 2008 5:23 pm

What's the part number of the '84 harness?

I looked at part number 61 11 1 243 194 in the ETK for a 1977 R100S. It's the main chassis harness, from what I can tell. I used ETK to find other parts usage. Here's what I see on the screen:

- diagram no. 61_0228 (from a catalog??)
- R60/7; R75/7; R100; R100/7T; R100S
- years '76-84

But...when I look up the same part the number for a '84 R100RT, I get 61 11 1 244 098... When I look at the parts usage for this part I get the following:

- diagram no. 61_0228 (same diagram)
- R80RT, R80TIC (police I believe), R100RS, R100RT, R100TIC (police?)
- years'76-84

Lots of similarity there...I think the police harness is going to have additional leads. Nothing definitive, but it appears this is the same part.

Kurt in S.A.

steve fewster · Post by **steve fewster** » Wed Jun 18, 2008 9:09 am

Thanks Kurt, for your help, I will let you know how I go.

Steve in Western Australia, Australia

steve fewster · Post by **steve fewster** » Sun Jun 29, 2008 9:34 pm

Hi Kurt, the 1980-84 wiring harness has too many variables on it to fit a 1977 r100s model, I have also a r1007 harness which is pretty close, I am having trouble with power to the coils, had to run a different power source to the coils, then got spark on both sides but one side very strong the other very weak, I changed coils, plug leads to no avail, can you help me on this one, definitely a head banging excise. Regards Steve.

schrader7032 · Post by **schrader7032** » Mon Jun 30, 2008 7:19 am

Steve -

Are these the original coils? Are they two single coils or one of the dual coil units? Are you still running the standard points and condensor? I changed over to a Dyna III ignition, but the power input to the secondaries on the coils comes from the kill switch to one of the terminals. Then there's a jumper from one coil to the other. The final terminal on the other coil has a wire that goes to the condensor and the points. When the points are closed, the coil is being saturated...when the points open, the power in the primary windings collapse and the spark is produced. Do you have a wiring diagram? Here is a diagram for the '78 models...I would think this should be the same for you especially in the area of the coils, etc.

http://www.omnilex.com/public/bmw78/78r100wire.jpg

You said you changed coils...do you mean tried another set of coils or swapped coils side to side? With single coils, that is one test to perform when you have problems on one side or the other...swap the positions of the components.

What is the resistance measurement from the end of one high tension lead all the way over to the opposite high tension lead? Generally, each spark plug wire should be around 5K ohms and each coil should also be around 5K ohms each. Total resistance side to side should be 20K ohms, plus or minus a couple of K ohms.

How are you checking for spark? I'm assuming you pull the high tension lead and stick a spark plug in the end. Be sure and ground the threads of the spark plug to the fins of the cylinder. This provides a path to ground for the energy being generated...just as if the spark plug were screwed into the heads. If this is not done, forcing the spark to jump the gap without proper grounding can, in the end and under certain circumstances, create a problem for the coils and possibly damage them.

Kurt in S.A.

steve fewster · Post by **steve fewster** » Mon Jun 30, 2008 9:05 am

Thanks guys, I will follow up all advice, the wiring diagram will come in handy I will let you know how I get along. Regards Steve.

VBMWMO · Post by **VBMWMO** » Mon Feb 15, 2010 2:52 pm

Hi I am restoring a R100S its not in good shape a lot of non bmw parts on it, I have brought myself a genuine parts manual, to cross reference for parts on other models that would be compatible to a R100S, any tips on how to read it would be appreciated.

Vintage BMW Motorcycle Owners