Installing a European Temperature Gauge on a USA F650

- David Braun - Flash - F650412

When I was living in France, I owned and rode a '96 F650 Funduro. It could not be imported into the USA, so I had to sell it in preparation for leaving. In the USA, I bought a '98 F650. There are many superficial differences. For me, one of the most annoying ones was the fact that the Euro F650 had a temperature gauge where the USA version has a clock. I don't need a clock. I have a wristwatch velcroed to the arm of my Aerostich. I wanted a temp gauge so I would have more info about the state of the motor.

In April '00, I received a flier from MotoBins in the UK. I had bought parts from them when I was living in France and was on their mailing list. Luckily the flier was forwarded to me in Colorado. Lo and behold, they were having a sale... eighteen percent off. Plus, as I was no longer living in the EC[1], I would no longer have to pay VAT[2].

Immediately, I visted and checked to see if they had microfiches for F650 parts and service as well as the temperature gauge and sender. They did. I ordered. MotoBins part numbers do not match BMW part numbers for some reason I don't fathom. At any rate, the Veglia temperature gauge (BMW #62 13 2 346 417, MotoBins #87060) listed for 33 UKP[3] and the sensor (BMW #? MotoBins #76500) was 9 UKP. Subtract 18% and add shipping and the pair cost me about US$60 or so.

But now I had to adapt them to the bike and vice versa...

First of all, the wrench used for the temperature switch[4] that runs the high-temperature idiot light for the USA version is about a 24mm wrench (I used a crescent) and the one for the Euro thermistor[5] takes a 14mm wrench. I had visions of needing to buy the Euro thermostat housing. But... the threads are identical. Changing the sensor is a direct replacement, requiring two wrenches. One slight caveat... the electrical connectors on the tops of the sensors are different. Yet, with a little chicanery, the USA wire slips right onto the Euro sensor, albeit orthogonally to the original. The little rubber connector-cover bootie can even be coerced into providing "safe sense."

Next, I removed the fairing to gain access to the back of the dash. There are eight gas tank screws and ten side-panel screws. Don't forget that there are two side-panel screws up at the front of the bike facing down.

There are 4 screws to remove the windscreen, which must be done to access the two large screws bolting the fairing to the support frame. Note: you only need pull the two screws near the top facing dead left and dead right. The two, sort of in the middle, facing front, hold the headlight and needn't be touched to remove the fairing. Unfastening the two large screws last puts you in a good position to pull the faring so you can access the turn signal harness plugs on the left and right and headlight and parking light plugs in the center. Wrassle that sucker off a there and put it where you won't trip over it.

My clock harness looked sorta jury rigged in the area of the time-advance micro switch. Anyway, the harness is a six pin Molex connector which uses 0.093" pins. It was Saturday, meaning my favorite 'lectronics parts place was closed, and I couldn't find a six pin Molex at Radio Shack. In any case, in order to get the temperature wire in there some, surgery was going to be required. I opted to buy a pair of male[6] & female[7] four pin connectors at RS, because they didn't have any three-pin connectors. (I hate Radio Shack. But sometimes they are the only option.)

Note: the clock has five wires. I assume they are 12V (battery), 12V (switched), ground, set-advance, and light. From this menu, we only selected the switched 12V and ground for the temperature gauge. I probed around with a voltmeter and wasn't completely sure I understood what was happening. But I certainly determined which wires were 12V-battery, 12V-switched, and ground. You don't want the battery 12V because the gauge will draw even when the bike is not running. CAVEAT: I don't have a Euro switch to turn off my lights. If you do, and you wire the temp gauge this way, you're gonna turn off the temp gauge with the lights.

Using a jeweler's screwdriver, I fished down between the metal and the plastic (of the Molex connector of the bike) to bend in the tabs (from the pin-to-pin side), so as to be able to extract the BROWN wire (ground) and the YELLOW/GRAY wire (switched 12V). After re-bending the retaining tabs, I stuck these two into the female of my 4-pin connector. Note: somewhere I have an old, busted, disassembled, telescoping radio antenna which I prefer to use as a Molex pin removal tool. But since I couldn't find it, I used the old, much less elegant, jeweler's screwdriver trick.

Next I went over to the other side of the dash and yanked out the "hot" idiot light. It has two wires, one VIOLET and one green/black. The VIOLET one goes down to the sensor. I cut the idiot light off, because the temp gauge doesn't come with illumination and the idiot light is a perfect fit. Furthermore, the plug removed from the hole[8] in the gauge fits the void left by removing the idiot light from the dash panel. (While I was in the neighborhood, I wrapped a small piece of electrical tape over the highbeam indicator light because it is just too damn bright for me at night.) If and when I come across a good substitute for the idiot light, I might get it and wire it in as an indicator for my hot grips. This is totally unnecessary, but the indicator icon IS a little thermometer.

I soldered a wire to the violet wire and taped up the connection all neatly, along with the green/black to keep it out of harm's way. I ran my new wire over to the vicinity of my new connector, cut, stripped, soldered on a pin, and installed it in the new connector..

There is one nut that holds in the clock that must be reused on the temp gauge. Be sure not to lose the washer when you remove the nut. Also, there is an o-ring up against the bezel of the clock that should be transferred to the temp gauge. The advance-set micro switch is pressed in and just pulls out.

The temp gauge itself has the aforementioned plastic plug in an illumination hole as well as three spade-type automotive quick connects. These connectors are labeled with icons for + and Ground, and the third says "SENS." If it is not clear what you should hook where at this point, you shouldn't be doing this without supervision.

I noticed that the gauge fit nicely into the hole vacated by the clock. However, it looked like there were certain cutouts not quite positioned perfectly for the temp gauge connectors. Since I had a selection of Stacons (crimp-on ring or fork, wire-to-screw connectors) on hand, I opted to make a small harness of my own and do away with the quick-connects. Fortunately, the three are each held by a nut, and can be removed quite simply. I patched my idiot light / illuminator into the hot and ground leads. Everything worked out and it seated completely. The only drawback is that I'll need to withdraw the gauge to change the bulb when it burns out. But that can be done without removing the fairing, as I planned ahead enough to allow sufficient slack in my harness. I could have drilled out the other location indicated on the back of the instrument. But I figured that was more hassle than it was worth for all the bulb changing I'll be doing. Hell, I put about 80k miles on an R80G/S and never had to change the bulb in the tach.

Before I reassembled the fairing, I tested the instrument by pulling the bike outside and firing it up. When the key is turned on, the gauge comes up slightly. I started and ran the motor at idle while I put all my tools and supplies away, pausing from time to time to note that the needle was rising. There are no numbers on the gauge; nothing but the word "TEMP," at about the midpoint of the needle swing. My goal was to run the bike until the fan came on and then went back off. The fan came on when the needle was roughly midway, centered on the word, "TEMP." After running for two minutes or so, the needle dropped to where it was ever so slightly below the "T" in the word when the fan stopped.

In heavy, downtown, summer traffic in France, I had seen the needle approach the red zone on my old bike, but never quite enter it. To me, this is better than a simple idjit light, knowing you're getting close to over heating. Besides, it is always a real pleasure to hit an open stretch of road after being stuck in traffic when the temp is up and watch the needle suddenly plummet. Also, with my US F650, I am never quite sure when to turn the choke off fully. Occasionally, I have turned it off, and then back halfway on, and then forgotten about it. With the temp gauge, I'll see when the motor has attained proper operating temperature and turn off the choke, as I used to do in France.

A few notes about reinstalling the fairing... The first time I removed fairing, it took a long LONG time to reinstall. And I munged up some of those stupid clips along the way. I finally figured out NOT to use any power screwdrivers when reassembling. I finally figured out to stick the hex wrench in the hole to make sure everything is all lined up BEFORE trying to insert a screw. And I got some extra clips to keep on hand. In a pinch, you can always swap a mashed one from an area you can't get behind to hold it during assembly with one that is, say, from the lower panel, which you CAN get behind. I never tighten any of the body screws any tighter than I can get them using the SHORT side of the Allen wrench in my fingers.

In the end, the bike was back in one piece, sporting a new TEMP gauge where that stupid clock used to be. The gauge looks every bit as good as stock because, well... it IS. Click here for a picture of the gauge installed.

Finally, thanks for reading this. That's why I wrote it.

- David Braun = - #F650412

[1] European Community
[2] Value Added Tax, varies, but runs around 15%, except on export items.
[3] United Kingdom Pounds, aka Pounds Sterling, about $1.65 each at the time I ordered
[4] Switch says: 115C, 81-25, F7, Jaeger
[5] Thermistor says: 120C, 04-03, K3, Veglia Italy, 12-24V
[6] 274-224, about $1.25
[7] 274-234, ditto
[8] It is a little rubber plug, about 9.5mm or 3/8" in diameter, with two wires, that holds a tiny instrument-type bulb.
[9] Ai putain! I forgot to write down all the numbers from the stickers on the gauge. C'est la vie. Le prochaine fois.

And on the Chain Gang Messageboard came this followup:
From: Fede
Date: 17-May-00
Subject: RE: Temp Gauge Install - Write-up

By the way about your good article. The temp displayed is more or less as follows: 1) The bottom indicates 40C. 2) The middle between 1) and the horizontal position marks 60C. 3) The horizontal position, over the word TEMP, indicates 80C 4) The beginning of the red line shows 100C 5) The end of the red zone shows 120C.

The engine runs always over 50C. Below 10-12C of external temperature, takes about 3-5 minutes to reach this temperature, and below 0C, till -6 or -7C runs slightly down of 50C. Over 12-13C takes only 2-3 minutes to reach the work temperature. The fan starts sligthly over 80C, perhaps 85C. In about 1-2 minutes, or less time, the temperature goes down 80C, including those days with external temperature about 40C, and/or intense city traffic. If the temperature is hot, about 80C, takes a few seconds (20-30) to go down when the bike runs over 20 Km/h. After riding a lot or in a hot day, if the fan is on, I let to run during a few seconds before stopping the engine, at idle revs. This is my own experience. Perhaps these ideas can be helpful for somebody... Specially those of you whose bikes lack of thermometer. But the cooling system of the F650 is one of the most efficient... Regards.

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