I should have known buying an Italian bike!
Took the Tuono out for its first proper run in the wet, filled it up with petrol and within a few miles it had developed a misfire on one (possibly both) cylinders under 5k rpm.
Bike has done ~200 miles in the dry and mostly dry since picking it up, has an Akra can but zero problems until now. Has a FSH and was serviced 2,000 miles ago.
It would pop and chatter and occasionally miss completely on both held steady at low rpm, but seemed to come back onto 2 just fine under load. So if I nailed it it would accelerate normally through the rev range, seem to fuel OK as it spooled down, but then once it dropped below ~5k start to pop badly again. It idled at a stop but unevenly, with the needle wobbling around idle rpm. Puttering around in 30 limits, it was also making a chuffing sort of noise from the airbox area - possibly one cylinder not firing?
No EFI lights at any time. Oil and coolant levels good, no pressure warning, no unusual temps. Nothing in the airbox drain tube. The airbox lid is sealed properly.
To rule out contamination (given that this started ~3 miles after refuelling), I've drained the tank. Because I saw no water and because I like to live dangerously, I chucked 6 liters of the fuel in my car, which has lapped it up happily over the last 30 miles or so. So unfortunately it wouldn't appear to be bad petrol.
I had wet-cleaned it, but it had been sitting in a dry garage for 16 hours after and did run fine for the first few miles. I don't use a jetwash or anything like that.
Only other thing that might have contributed is that in the course of checking that the air filter had been replaced at the last service, I popped the tank up and cleaned up the throttle spring at the cable ends, and also sprayed some silicone lube liberally on cables and tubing for good measure.
I don't know if getting silicone lube on the back coil housing or down one of the rear plug recesses could have caused the problem?
Second query arising from the above. Because I'm dumb and am used to low-pressure fuel systems with nice, simple butterfly clips, I managed in the course of trying to remove the hose clip midway along the tank --> injector line to break off the end of the white plastic valve. Like I said, dumb.
Is that a non-return valve? Or a tiny filter? Either way, could I run the bike without it and just substitute a 6mm or 1/4" plastic union (or run a new length of hose, but I don't want to break anything else)?
Alternatively, is it safe to glue the broken end back onto the valve? I'm a bit leery of doing that as I'm not sure whether glue (epoxy or superglue) will stand up to petrol and radiated heat, since if it breaks again the hose will instantly come off and spray petrol all over the engine. I'm guessing no. Although would this be OK just for purposes of cleaning up the plug and coil connectors with contact cleaner and running it on a paddock stand to see if a dry-out has fixed the problem?
I have ordered a new check valve/filter/whatever it is, but who knows how long that will take to get here.
Took the Tuono out for its first proper run in the wet, filled it up with petrol and within a few miles it had developed a misfire on one (possibly both) cylinders under 5k rpm.
Bike has done ~200 miles in the dry and mostly dry since picking it up, has an Akra can but zero problems until now. Has a FSH and was serviced 2,000 miles ago.
It would pop and chatter and occasionally miss completely on both held steady at low rpm, but seemed to come back onto 2 just fine under load. So if I nailed it it would accelerate normally through the rev range, seem to fuel OK as it spooled down, but then once it dropped below ~5k start to pop badly again. It idled at a stop but unevenly, with the needle wobbling around idle rpm. Puttering around in 30 limits, it was also making a chuffing sort of noise from the airbox area - possibly one cylinder not firing?
No EFI lights at any time. Oil and coolant levels good, no pressure warning, no unusual temps. Nothing in the airbox drain tube. The airbox lid is sealed properly.
To rule out contamination (given that this started ~3 miles after refuelling), I've drained the tank. Because I saw no water and because I like to live dangerously, I chucked 6 liters of the fuel in my car, which has lapped it up happily over the last 30 miles or so. So unfortunately it wouldn't appear to be bad petrol.
I had wet-cleaned it, but it had been sitting in a dry garage for 16 hours after and did run fine for the first few miles. I don't use a jetwash or anything like that.
Only other thing that might have contributed is that in the course of checking that the air filter had been replaced at the last service, I popped the tank up and cleaned up the throttle spring at the cable ends, and also sprayed some silicone lube liberally on cables and tubing for good measure.
I don't know if getting silicone lube on the back coil housing or down one of the rear plug recesses could have caused the problem?
Second query arising from the above. Because I'm dumb and am used to low-pressure fuel systems with nice, simple butterfly clips, I managed in the course of trying to remove the hose clip midway along the tank --> injector line to break off the end of the white plastic valve. Like I said, dumb.
Is that a non-return valve? Or a tiny filter? Either way, could I run the bike without it and just substitute a 6mm or 1/4" plastic union (or run a new length of hose, but I don't want to break anything else)?
Alternatively, is it safe to glue the broken end back onto the valve? I'm a bit leery of doing that as I'm not sure whether glue (epoxy or superglue) will stand up to petrol and radiated heat, since if it breaks again the hose will instantly come off and spray petrol all over the engine. I'm guessing no. Although would this be OK just for purposes of cleaning up the plug and coil connectors with contact cleaner and running it on a paddock stand to see if a dry-out has fixed the problem?
I have ordered a new check valve/filter/whatever it is, but who knows how long that will take to get here.
