Hi All recently acquired a rough 749r that has been stood for 4-5 years. Hadnt been run in that time. Mileage shows 3000ish but last Mot it was 6000 go figure! I have drained the fuel, cleaned the tea bag fuel filter blown through the other fuel filter and checked that the fuel pump is priming and delivering fuel (I did this off the bike). Changed oil, oil filter and give it fresh fuel. spark plugs changed. Cranked with plugs out until oil pressure light went off. Bike wouldnt turn over with starter button just a click so changed the relay and solenoid, still click on the button used another battery still click, boosted from van battery still click! I have to bridge the solenoid to get it to turn over, its very slow though. Will not run. New CPS fitted as JP diag threw up the code. Will not run. Reset TPS. Checked loom and cant see any issues, even run An extra ground to starter motor bolt as suggested by someone on here I think. Spark evident on vertical albeit looked a bit weak, couldnt seem to get one on horizontal. So swapped out ecu for a spare ecu I had still. Will not run. On cranking it is banging and popping out of exhaust and popping out of air box, termi silencers are off at the minute. It did have a PC3 attached so Ive disconnected that. Will not run. Fuel pump primes on key on, when cranking Ive noticed that TPS reading increases from 2.1ish upto 12 then 33 without touching throttle, any ideas or is this a JPdiag issue? No codes in Jp diag at the minute. Any suggestions or ideas more than welcome please. Thanks
I had a similar click , no start on my 749R a couple of years ago. Tried all sorts of things (relay, check earths etc) and then @Chris dropped by and suddenly, a revaluation…battery. New battery - started. Have you checked ecu earth fly lead is clean and grounded properly?
Sounds like it could still be a fuelling issue. I'd replace the main fuel filter and then think about the injectors, if still a no go.
Yes the ecu ground lead is attached to the battery box fixing post, all clean. I thought the van battery with jump cables would’ve sorted it but still clicking. Tried my 1299 battery and a lifepo battery still the same unfortunately.
the slow cranking is worrying as looking at what you've done to improve this, it can only mean either a problem with the starter itself or the engine is partially-seizing up for some reason. I'm guessing you are happy that battery terminals are corrosion free? A careful touch by hand on the leads and terminals after an attempted crank might shed some light as something is likely to be getting hot. You could attach a good set of jump leads direct to starter terminal and obviously engine earth for negative from a known good battery to confirm it's one of the above two options.
The jump leads are getting warm after cranking and battery terminals are clean. I’ll try the jump lead direct to starter over the weekend. Thanks
Hi, if the value coming from the TPS in JPdiag is jumping as described than most likely your TPS sensor is faulty, you have to change the sensor and make a TPS reset. Andreas See: https://www.ducatiforum.co.uk/threads/749-999-money-saving-tip-for-broken-tps.14226/ and https://www.ducatiforum.co.uk/threads/how-to-749-999-tps-replacement.24535/
Turns over fine touching the starter cable direct to battery. Will not turn over through solenoid. Still Will not start, just backfiring into air box and out of exhaust. No fault codes showing Any ideas??
Good news, if only on the starter/tight engine front. On the no start problem, the fluctuating TPS is worthy of closer examination as obviously wrong. Have you found any corrosion in ignition-related connectors at all?
If you have total loss spark plugs fitted , I would certainly start by changing them first. Had problems with mine found to be the plugs. Do not use throttle only cold start/ choke on start up . They are very easy to over fuel.
Took ground out of battery terminal connector cleaned them all and recrimped. New ground to vertical cylinder and starter motor. new NGK plugs installed. Trying to Start with a closed throttle, then a little open throttle has the same effect.
So if it spins over when jump leads are connected direct to the starter but not when connected to the battery that implies to me there’s an issue with the battery or the solenoid. I know you said you replaced them but was it with new? As youve tried a variety of different batteries I’d say the culprit is the solenoid. However, that appears to not be the only issue as even when spinning over it doesn’t start. The TPS readings do look suspect and logic would dictate that if the ecu thought the throttle was open that much it would be dumping too much fuel into the system and in effect flooding it. Are the plugs soaking wet if you check them? If not then the TPS readings in JPDiag may be a red herring. If it were mine I’d focus on the possible solenoid issue first and get the motor spinning off it’s own battery every time, then move onto the next issue.
These bikes don't have a choke. The fast idle lever does the exact same thing as slightly opening the throttle.
