Tech Tip: clutch cut out switch

[spizzoil]

so came to the bike this morning and bike wont start so me thinks its the cold and the damp.so get me space heater heat gun out and warm the garage up heat gun on all the connectors and still wont start check all the fuses still no go got now check light on clocks .so lets start with the starting procedure make sure we are not in gear kill switch is on and battery is good and still nothing happens .so a bit confused dot com .so fuel pump primes good fuel in it what else to look at clutch cut out switch so me pulls it in a few times check spade ends check wiring with test meter and all ok. so now I am really at confused.com then a post that frody put up on the old org came into my head of how after market clutch and brake levers he had to put a cap on the end as the clutch would not push it in fare enough. so what about where and tare.so took it off wired it up turned it on waited for fuel pump to prime pressed the plunger on the clutch switch and with my ear to the tank could hear the fuel pump selinoid clicking and press starter and fired up .so it shows that they wear to a point that the clutch cant push it pass the dead spot but your thumb can, so new one on order .does this clutch cut out switch do anything else or is it just for starting .nice little fix if you are away from the tools on ride out . is it used for anything else like gear sensor changing gear .

[seth]

I had this years ago on a set of aftermarket leavers I ended up cutting a small piece of plastic and glued it to the leaver so the clutch switch worked properly again was fine after that till I replaced the leavers.

[spizzoil]

thanks seth does this switch does it do anything after you have started the bike up

[seth]

@spizzoil
I remember from somewhere the ecu needs to know the clutch switch is there after starting or it goes into a strange mode.
On the old org someone made a bypass and ran the bike on a dyno it had a different power curve so a different map when it was bypassed with back to back runs on the same bike.
I'm hoping someone else remembers more on this
 

[spizzoil]

thanks looks like I cant ride with it off the clutch

[seth]

It will run but i dont know if it'll run properly .
Is the switch or the leaver as any modern Suzuki will use the same switch bandits, vstrom, sv use Robinsons parts guide to check which bikes share the same part .
It should be easy to get hold of .

[Andre]

What I have read is that ignition timing and injector time will be changed each time.

[seth]

Thanks Andre
I remembered it did something but wasn't sure how it changed things.
Top responce as ever. 

[seth]

A new clutch switch from Robinsons is £20 .

[grog]

If left bridged, ecu will set map as neutral mode. Motor will run diff. Fuelling, timing etc.

[gsxbarmy]

Essentially with the clutch switch off it leaves the engine in "start up" mode - as others have said different timing map, fuelling etc, so yes it does need it.

One thing you might try spizzoil - if you take the (old) clutch switch off, there is a very small hole underneath - if you spray some contact cleaner in there, sometimes that can rejuvenate the switch for a while (as crud gets into the mechanism making a poor contact). Still need a new switch, but can work as a temporary "keep you going" sometimes

[froudy]

As mentioned, I know that they don't like running well with the switch bridged out of circuit

[grog]

switch operates same on all F1 enabled suzuki. gsxr lose over 500 revs with limiter when shorted. its just the map they stay in, slightly diff in models but just neautral or start mode. some even fit a toggle switch, not sure why, seems a good safety thing to me. better than starting and rolling off stand. with mine, dont know if you blokes have noticed, at stop in gear, if i let clutch out a bit, where switch opens/closes, revs change and motor sounds slightly different. thats maps changing.

[Andre]

An informative video measuring injector time with and without switch bypass on a SV650.  https://www.youtube.com/watch?v=4_qnGJihHvM

[grog]

Interesting clip Andre. I read somewhere that if clutch switch is not closed for a certain amount of time, long run in 6th gear, ecu then reduces injector time for optimum fuel economy. I think that could be true, mine uses lots less on a big long run.