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post #1 of 86 (permalink) Old 12-01-2010, 04:06 AM Thread Starter
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Bonneville Clutch Safety Switch

Of all the safety gizmos I find the clutch safety switch the most annoying. This stems from my life-long habit of being able to finely control the degree of throttle opening for starting, and operating the start button with my left hand. For years I've found a quick glance at the neutral light and the slight movement of the machine forwards or backwards sufficiently safe to know that the bike is not in gear.

On my SE the need for fine throttle control for starting is no longer there. The engine will simply start with a quick glance at the button and no throttle at all, but I still find it annoying.

Warning: Offensive non-PC Rant mode ON

This is of course not sufficient for our risk-averse Society and its safety neurosis. They must ensure that no-one has an accident or dies, EVER!. This is of course cheating Darwins theories, ensuring that rather than survival of the fittest, the human gene pool overflows with idiots and incompetents. Witness the many electronic aids that modern cars have: ABS and brake assist so you don't have to learn to brake properly, and now many cars come with a "Hill assist" so there's no longer the need to master accelerator/clutch control to start on a hill without rolling backwards... Electronic suspension and steering controls that forgive and even correct your trespasses and avoids skids, and many other complex and expensive devices designed to enable utter morons to take liberties and drive like twats without suffering the consequences of their folly.

To enable them to do that, makers supply them with ever-more powerful cars, witness the latest VW Polo GTI 1.4 TSI has a massive 180 bhp...yes, from a 1.4 litre engine. It has a clever engine with a supercharger AND a turbocharger combined. Not only that but the twerps don't even have to change gear in it: it comes as standard with a DSG direct-shift auto box...

My niece, for example, is utterly thrilled because her car turns on the windscreen wipers and headlights automatically and also has parking sensors, this is of course not enough, she now wants one of those cars that park themselves...I despair.

We have suffered from this since the introduction of things such as power-brakes and power-steering. This enables 100-Lb over-indulged little girls to drive daddy's monster SUV's fitted with a locomotive engine, while talking on their mobile phones, applying their make up and listening to Lady Ga-Ga on their 2000 Watt stereos. I know this is sexist, (I hope Rose isn't reading this...), but the rot started in the US with Charles F. Kettering of Dayton laboratories (DELCO) inventing the self-starter in 1912...This was the starting pistol for women to take up driving...

On vehicles without a clutch, like twist-and-go scooters, you must press the brake before the starter will operate. I can just about understand it on automatic gearboxes where unskilled or semi-senile operators can wreak havoc. Witness how many accidents happen when some dribbling 97 year-old half-blind driver in a 3 ton automatic SUV ploughs through a crowded street while adjusting his colostomy gear...

Look, just give me the facts and stop all this misogynist, cantankerous, Hispanic macho claptrap already!...

Once again a cursory Google search finds lots of people having trouble with yet another simple device that ought to last years and millions of operations, and yet fails with monotonous regularity. Just Google "clutch switch" and hordes of victims ask how to disable it.

The switch itself is an extremely simple, sealed ON-OFF device fitted with wiping contacts. The contacts are operated, as in the side stand switch, by a tiny plunger that touches part of the clutch lever. The only protection from the elements is a rubber sleeve or boot over the top held by a spring clip. If you slip back the spring clip and roll the rubber back you can see the connections to the switch contacts. Being of the wiping type they enjoy a certain degree of self-cleaning action, not much but it's there.

Nevertheless the contacts will eventually wear, tarnish and corrode and that will be that: Engine won't start in the middle of Death Valley or somewhere equally embarrassing and inconvenient.

It's interesting to note that the design and construction of the switch itself is as old as the hills. My 1996 Virago has virtually the same switch to operate the front brake light. Lots of other bikes use them.

How does it work?

The switch is of the "normally open" type, normally in this case in that the contacts are open with the clutch lever in the normal driving position, clutch fully engaged, switch plunger pressed-in fully. To enable the engine to start the contacts have to be closed, this being achieved by pulling the clutch lever which frees the pluger/spring assembly to return to a rest position and close the contacts.

How can I test it?

You can try to access the switch terminals under the rubber boot by rolling it back and trying to connect your test device to the terminals so exposed. It's not easy, the boot keeps springing back and can not be easily held while manipulating the testers probes.

It's best to remove the headlight and find the connector that also includes the connections for the flasher and dip switches. It's found inside the headlight shell.

It's not that difficult, just remove the headlight itself, two Philips screws, either leave the light hanging by its wires and resting on the front fender with a cloth under it to prevent scratches, or unplug the whole thing and put aside, and look for a 10-way WHITE connector. If confused by all the spaghetti there, tug at the wiring loom that comes from the left handlebar switch cluster and see which connector moves inside the shell. On mine it's the only white one.

Pushing on the locking tab separate the two halves of the connector, (try not to pull on the wires if you can help it grab the connector mouldings instead), pull the connector apart.

On the connector half that goes to the switch cluster (the "male" half) identify the two contacts with the wire colours stated earlier (Black and Black/Red) these are numbered in faint moulded figures on the connector shell: Black is pin 5, and Black/red is pin 9. Use a flashlight to see properly.

Important: The wire colours can change. The wiring diagram I have says the Black/Red wire should be Black/yellow...the Black comes out of the other loom connector (the female pasrt) as Black/Orange and the Black/red changes to Black/silver...It's a joke. Best to go by the connector numbering, pins 5 and 9. These don't change.

Connect a continuity tester or multimeter switched to the low Ohms range to those two contacts. Note the reading: It should give infinite resistance or no continuity. Pull the clutch lever all the way to the handlebar and the reading should change to 0.01-0.03 Ohms or virtually full continuity. This means the switch is working. Repeat several times in case here's an intermittent contact.

How can it be bypassed?

Those two wires have to be shorted together somehow for the engine to start. If you intend to remove the switch altogether cut off the wire loom as it enters the rubber boot, discard switch and strip and connect wires together. Insulate and tuck into the sleeved wire loom on the handlebars.

You could of course also short these wires out inside the headlamp shell, it's up to you.

I want to remove the switch altogether, how is it done?

It's surprising how many people do not know how these switches are fixed on. I've seen people tug and pull and twist until they're blue in the face. Some even succeed in removing it by attacking it with ever more brutal tools eventually managing to wreck it.

It's worth removing from its housing occassionally just for inspection and maintenance, even if you don't intend to do away with it. Silicone water-proof grease can be applied to its plunger and, if you're anal, the rubber boot can be pulled back, the terminals inspected, and the inside of the boot filled with dielectric grease.

The fixing consists of a couple of sprung tabs moulded on the switch body itself. One of them springs out and locates in a square cut-out or "window" under the handlebar lever casting. The other folds up and retains the switch under a little pressure inside the housing. Look under the switch, find the little "window", poke a sharp instrument in there and push-up while pulling on the switch body. It'll come out without difficulty. To re-insert just align the locating tab on the switch with the notch at the top of the casting and push in until you feel or hear a "click" meaning the sprung tab has dropped into the window once more.

Come on then, just one more little whinge...

Unless you cut-off the switch from its wiring loom altogether you can't just get rid of it. It's an integral part of the wiring loom of the left hand switch assembly and, of course, the switch cluster itself, and can not be separated.

I can't give you a part number if you need to replace it either. It doesn't exist as a separate part. If you want a new one you'll have to buy and replace the whole assembly, clever eh?.

Just buy Part Number: T2040328 at a cool 101.85 (USD 158) to replace a switch sold separately for other models (see below) for less than $14.

It is available as a separate part for other bikes in the range: the Daytona, Speed triple, Sprint ST, Tiger, Speed Four, etc, under part number T2505005. It comes with its own wiring loom and connector, but this will have to be discarded and the wires spliced onto our own wiring loom. The cost is a reasonable 9 (USD 14).
travis59, Andeone, Psycrow and 3 others like this.

Last edited by Forchetto; 12-01-2010 at 03:28 PM.
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post #2 of 86 (permalink) Old 12-01-2010, 04:32 AM
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post #3 of 86 (permalink) Old 12-01-2010, 05:43 AM
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this is almost to good.....

Thanks Mr!

I never seen so many sissy men on a bike forum. "Good judgment comes from experience. Unfortunately, the experience usually comes from bad judgment."
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post #4 of 86 (permalink) Old 12-01-2010, 07:31 AM
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I am going to disagree regarding ABS. Even well-trained drivers cannot out-perform a properly operating ABS. Close, but not as good.

Given the opinions expressed regarding power- brakes and steering, I assume you also bemoan the fact that we have electric start at all, and not a kick with compression release (or does a compression release make it too easy?).
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post #5 of 86 (permalink) Old 12-01-2010, 09:41 AM Thread Starter
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Compression release? that's a decadent, degenerate frippery, that is...
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post #6 of 86 (permalink) Old 12-01-2010, 10:07 AM
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What can I say? You've done it again - nice one, sir!
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post #7 of 86 (permalink) Old 12-01-2010, 11:35 AM
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Thumbs up

Originally Posted by bobbo View Post
What can I say? You've done it again - nice one, sir!
+1, top post as ever well done.

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post #8 of 86 (permalink) Old 12-01-2010, 06:49 PM
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Originally Posted by Forchetto View Post
Compression release? that's a decadent, degenerate frippery, that is...
lol @ "frippery". Nice...
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post #9 of 86 (permalink) Old 12-01-2010, 08:10 PM
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Well Said

The strange thing is that a couple weeks ago the clutch safety switch started acting up on my Rocket 3. A little WD40 solved the problem for the time being. The next time the wire cutters come out. At least it not a feature on the Scrambler.

Try owning on these and you will sacrifice a sheep to the compression release Gods every time you go to kick it over.........
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post #10 of 86 (permalink) Old 12-01-2010, 10:12 PM
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Awesome Forchetto! I've been trying to figure out how to remove that switch so that I could put some dielectric grease in there and just gave up. Now I know! HAH! I'll add this to my pre-season checklist.


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