PDA

View Full Version : Engine dies during clutch engage.



Mikkel
12th October 2007, 10:14
Hi guys,

I had a weird thing this morning as I went to take the bike to work. I started the bike and let it sit for about 5 mins to warm up before I went out to get up and leave. I get on the bike, take the stand up, squeeze the clutch, shift down into 1st, revs it slightly and gently engages the clutch. *ENGINE DIES*
Thinking "Hmmm that's weird" I restart the bike, rev it higher, engages clutch *ENGINE DIES*. Rinse and repeat four or five times - I don't even feel the slight tug of the clutch biting - as soon as the clutch starts gripping the tiniest amount the engine just stops as if I'd hit the kill switch. And I have to note that at this point it's warm enough that I've taken the choke off entirely. I fiddle around a bit (just checking that everything is ok - roll the bike a bit back and forth etc) - try a couple of times - fiddle around a bit more - and then it just works and my ride to uni was nice, quick and carefree.

Anyone got an idea about WTH is going on here?

It's an '89 Kawasaki zxr250rr btw.

Cheers
Mikkel

vifferman
12th October 2007, 10:18
Does it have a microswitch on the clutch lever? A lot of modern bikes have such a device, to stop you starting the bike with the bike not in neutral and the clutch not engaged.
Should be easy enough to tell - pull the clutch in/out a few times with the motor off: should be able to hear a faint click from the lever. There will also be a wire plugged into the clutch boss.

Kwaka14
12th October 2007, 10:18
Kill switch on the side stand maybe?

idb
12th October 2007, 11:53
Not sure but can anyone tell me if a gearbox can get worn enough that the gears start binding?
I imagine it would be pretty stuffed if it got to that point.


Failing that make sure the handbrake is off.

tri boy
12th October 2007, 12:04
Sidestand switch, or clutch switch is playing up. Try to CRC both and try again.
If it still stalls the engine on clutch engagement, ring your local workshop and ask which wires can be bridged to be able to ride it to them.
Good Luck.

NighthawkNZ
12th October 2007, 12:12
Sidestand switch, or clutch switch is playing up. Try to CRC both and try again.


Those would be my guess too...

unrealone
12th October 2007, 12:43
Did you try starting the engine with the clutch in and stand up (Also try with it in 1st)? This should satisfy all neutral switches and let you start the engine.

xwhatsit
12th October 2007, 13:18
Apart from the bikes that only let you start in neutral :doh:

Even if you rev the complete shit out of it, then slowly let out the clutch, it still does this?

ManDownUnder
12th October 2007, 15:22
My money is on the side stand kill switch. Clutch switch is working or the bike wouldn't start at all... side stand switch is detecting a "stand down while in gear" situation and killing the electrics.

If you can't get it going, remove the switch, twist the wires together, ride to the shop and get another one... or simply leave it off and jumper the two wires.

xwhatsit
12th October 2007, 15:54
No but he can change into gear fine. It's only when he lets the clutch out it gets upset. That was what was confusing me, too.

ManDownUnder
12th October 2007, 16:01
No but he can change into gear fine. It's only when he lets the clutch out it gets upset. That was what was confusing me, too.

If it's like the RF, I have a side stand switch and a clutch switch.

If the side stand is down (i.e. contacts are open/open circuit) then the clutch must be in otherwise no starting. It means I can start it in gear but not let the clutch out/ride away.

I'm guessing the bike dies "suddenly" i.e. no load on the engine, but it's like the kill switch was hit.

Even if the side stand is up, if the switch is poked, it's keeping the kill circuit active - killing the bike as soon as the clutch (and the clutch kill switch) is also released (goes open circuit)

Go for the technical tap and CRC solution first (technical tap - handle of biggish screwdriver and whack it "just hard enough"). Squirt squirt. As Ii said - to text it, take the switch off, short the wires together and give it another go.

I assume the side stand is up... yes?

xwhatsit
12th October 2007, 22:41
Oh I see. You can still start it in gear, as long as the clutch is in. I thought it was a logical AND, not a logical OR -- the clutch must be in, and it must be in neutral. That's what the other silly Suzukis I've encountered have done.

Mikkel
13th October 2007, 12:52
Hmmm well it's periodic and I managed to get the bike out and about just fine in the end. But I reckon it could be a stand sensor if it has something like that (it's an '89 - would they have it back then?) since I gave up put the stand down got off the bike and thought FFS this can't be true and had another go at it.

But yes, it starts fine whether in neutral or in 1st with the clutch in. It just dies as soon as I try to let the clutch out - and it does so irrespectable of revs. But as I said - a periodic failure that I couldn't reproduce even if I wanted to. But I guess it could be the stand thingie...

ManDownUnder
13th October 2007, 13:20
Hmmm well it's periodic and I managed to get the bike out and about just fine in the end. But I reckon it could be a stand sensor if it has something like that (it's an '89 - would they have it back then?) since I gave up put the stand down got off the bike and thought FFS this can't be true and had another go at it.

But yes, it starts fine whether in neutral or in 1st with the clutch in. It just dies as soon as I try to let the clutch out - and it does so irrespectable of revs. But as I said - a periodic failure that I couldn't reproduce even if I wanted to. But I guess it could be the stand thingie...

FWIW my bike has both switches is a '94 and does exactly what yours does (i.e. can start in any gear if the clutch is in). Later models insist it's in Neutral.

If it is the side stand it'll be easy to reproduce (or permanently avoid).

To avoid - replace the side stand switch - or pull the wires from the switch and twist/solder them them together (or possibly keep them apart although I think an open circuit would be a "kill" condition)

To test, pop the wires from the switch, keep them separate and see if it does what you describe (my money is on the fact it does).

Then twist them together and try again - problem goes away? It's the switch.

Bren
13th October 2007, 13:33
But I reckon it could be a stand sensor if it has something like that (it's an '89 - would they have it back then?)


Funny thing happened to me....My bike still aint on the road yet but I still potter about with it. I toolk my bike outta the back yard, and put the bike on its stand so I could close the gate behind me....Then got back on the bike and tried to go down the driveway...My engine kept on dying as I engaged ino gear. I couldnt figure it out and thought sh1t, not another prob....then I noticed sidestand still down...and remembered a bit of useless info bout the cut off on it...That was my problem....BUT, my bike is a 1989 GpX250, so same year kwaka as yours......so in all reality yours does have a kill switch too....

Mikkel
13th October 2007, 15:57
FWIW my bike has both switches is a '94 and does exactly what yours does (i.e. can start in any gear if the clutch is in). Later models insist it's in Neutral.

If it is the side stand it'll be easy to reproduce (or permanently avoid).

To avoid - replace the side stand switch - or pull the wires from the switch and twist/solder them them together (or possibly keep them apart although I think an open circuit would be a "kill" condition)

To test, pop the wires from the switch, keep them separate and see if it does what you describe (my money is on the fact it does).

Then twist them together and try again - problem goes away? It's the switch.

As I got back from todays ride I just tinkered away with this and I found that having the stand down will reproduce the exact behaviour I was describing above. Now the question is whether I had a brainfart and forgot that the stand was down or if the switch does indeed have a semi-loose connection.

Cheers :)