Oilhead Tech Pages


A Better Method of Connecting Your VOM to the TPS

John Petty


While attempting to perform a 0=0 TPS adjustment, I had trouble getting a stable electrical connection to the #1 wire by using a safety pin or straightened paper clip. Just then, I had a light bulb appear over my head.

I went into the workshop (the one the wife thinks is a storeroom) and got some 16 gauge wire. It is the stranded type, not the solid wire. I stripped off about 1.25-1.5 inch of insulation and slipped the end down into the socket of the #1 connector. I was very careful not to let any strands of wire get into the #2 wire connector! Taking a small flat screwdriver, I tucked the strands of wire down into the recess where the outer socket of the TPS connector fit inside the weather-tight boot. There are 2 slots that match two ridges on the plug for a no-fail alignment so that you can not turn the plug around and try to connect it the wrong way. The slots are about twice as wide as the ridges and allow the stranded wire a place to exit the plug.

(click on all photos for larger versions)

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Here is a photo of the wire after I gently pulled it out of the plug so that you can see the shape of the end (the left end in the picture) that went into the plug <photo 4>. This allows the plug to be reconnected with a really nice tap on the signal from the #1 TPS wire. I wouldn't use any thicker gauge than the 16 GA I used. In fact, 18 GA is probably just about right.

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Hook up the positive probe of the VOM to the other end of the wire <Photo 3> and connect the negative probe to the battery or a good ground. Then do your Zero=Zero as described by Rob Lentini in the R11 tuneup manual.

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After also switching out the spark plugs for single electrode Autolites and swapping in the R1100GS air intakes, I did a throttle balance with a Twinmax using the throttle stop screws with the air bleed screws set at their base settings as described by Rob Lentini in his "ZERO = ZERO" article:

R1100 RS/RT: 1 1/2 turns from closed
R1100 GS/R: 2 1/4 turns from closed
R850R: 2 1/4 turns from closed

Secondly I set the off-idle at 2000 RPM. Then I took the RT for a shakedown cruise with the Twinmax strapped to the tank with a bungee net and no body panels attached. Yes, it was downright ugly but it worked. I pulled into a parking lot a couple times to get the balance adjusted so that it was balanced at 4000 RPM in third gear. 4000 RPM, on the road and under load, is NOT the same as 4000 RPM in nuetral on your carport or driveway!

My friend never realized just how smooth a 1996 R1100RT could run!


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R-Tech pages maintained by: John Petty for the original author(s) and the Internet BMW Riders
Last Update: 09 September 2010