Intermittent slow speed cutout

Message

spiderwheels · #1 Post by **spiderwheels** » Sun Sep 30, 2018 8:10 pm

My old Falco is upset about the new Falco so it's decided to develop an intermittent cut-out. It only happens cuts out at slow speed. Junctions and mini roundabouts are a favourite. Hot or cold doesn't seem to matter. If it's got enough momentum it will bump itself straight back to life, otherwise it fires straight back up with a press of the starter.

So far I've blanked off the side stand switch and swapped fuel pumps (actually complete fuel tanks but that's another story). It was perfect for the first ride following the side stand switch fix.

It may be a coincidence but it seems to have started around the same time I fitted a new battery (genuine Yuasa). The connections are clean and tight - at least at the battery end.

What to look at next?

fatboy · #2 Post by **fatboy** » Mon Oct 01, 2018 6:12 pm

May be a long shot but try disabling the fuel cut off/tilt switch .
All you have to do is stop the sliding contact from sliding, can be done with tape or bits of tubing....
I have had a few fail on me and cause similar issues .
Also look for any wiring insulation fails between engine and frame rails,good luck and hope it's not too painful

DavShill · #3 Post by **DavShill** » Thu Oct 04, 2018 11:43 am

I had an intermittent "cut-out" problem. It took ages to identify. It turned out to be a poor connection in the white block connector in the power line to the fuel pump. Left hand side under the tank. I simply had to pull the connecter apart and prise the pins open a little to make a better connection.

Worth a look?

spiderwheels · #4 Post by **spiderwheels** » Thu Oct 04, 2018 8:44 pm

Yes definitely worth a look thanks. How did you figure out it was that connector?

I've checked the tilt switch. However, I can rule it out because if I cause it to trip the bike won't restart without cycling the ignition off and back on. If it cuts out it restarts on the button.

Firestarter · #5 Post by **Firestarter** » Fri Oct 05, 2018 6:35 am

spiderwheels wrote:Yes definitely worth a look thanks. How did you figure out it was that connector?

I've checked the tilt switch. However, I can rule it out because if I cause it to trip the bike won't restart without cycling the ignition off and back on. If it cuts out it restarts on the button.

You can run without the tilt switch completely, just disconnect it. You'll get a flashing EFI message, but the bike will run without it. Can then figure out if you still get the cut-out and re-connect (or replace) the switch

DavShill · #6 Post by **DavShill** » Fri Oct 05, 2018 2:27 pm

I noticed that the fuel pump was not priming with the tank in the lifted position but as I lowered the tank the connection made good and the fuel pump primed.

spiderwheels · #7 Post by **spiderwheels** » Sun Oct 14, 2018 12:52 pm

I found a poorly crimped bullet connector on the blue/grey wire to the engine stop relay that I suspect is the issue. That would be a like hitting the kill switch.

I think the bullet is due to the partly disconnected datatool alarm that's always been in there. I took the opportunity to rip the remains of that out too.

I'll road test it next time it's dry.