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Discussion Starter #1
I'm needing some advice trouble shooting the reason my 1998 748 won't start.

What I've done so far. History. After replacing a failure and short in the connector from the stator to the Voltage Regulator rectifier while on the road the bike ran just fine. I tested the VR with a Mulitmeter. Battery was charging at 14volts at 5k rpms. I rode it for a few days but noticed that it was slow to crank and sounded like it had low power. I tested the battery (it's a year old) and it's holding 12.6 volts. A few days later with a fully charged battery I got nothing. Turning the key to on it appears to have power, fuel pump whirls to life, injectors prime, and running lights are strong but nothing. Only the Solenoid clicks.

I've replaced the Solenoid, the Voltage regulator, the two relays under the seat and still nothing, checked the wiring and still nothing....

Does anyone have any other ideas that can help?

Thanks.
 

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Welcome to the forum!

Have you tried running a cable from the battery + terminal to the starter motor to make sure it turns over? Sometimes the starter solenoid fails and the starter motor doesn't get anything. You my simply have a bad cable or starter motor. I wouldn't go too crazy, sounds like everything else is in tip top shape after you diagnosed the short in the stator cable. Good job on that one! It's a common problem.
 

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There is a small wire with a white plastic female connection located near the bottom of the start solenoid, easy to miss. Check this connection as the bike will not start without it being connected.
 

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Welcome to the forum!

Have you tried running a cable from the battery + terminal to the starter motor to make sure it turns over? Sometimes the starter solenoid fails and the starter motor doesn't get anything. You my simply have a bad cable or starter motor. I wouldn't go too crazy, sounds like everything else is in tip top shape after you diagnosed the short in the stator cable. Good job on that one! It's a common problem.
Thanks Tuned and Spudd. I've replaced the solenoid and checked the connections and everything is good. How do I run a cable from the battery to the started to check if it turns over?
 

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Thanks Tuned and Spudd. I've replaced the solenoid and checked the connections and everything is good. How do I run a cable from the battery to the started to check if it turns over?
Just take a jumper cable, connect it to the battery positive terminal and carefully hold it to the terminal on the back of the starter. Sometimes you can just tap it quickly and hear the starter spin the bike over, that's usually enough for an indication of the starter working. It's an old bike, so the starter could just be bad. If you do this test and it's dead, I had no problem pulling the starter apart and replacing the brushes, which are usually what goes wrong. But used starters are cheap! :)
 

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Discussion Starter #6
Hello Tuned. I've given that a try and had no positive response. So, I've ordered a new starter motor and have committed to cracking open the alternator cover. While I'm in there I'll check out the stator. The bike is going on 18 years old so new parts won't hurt.
I've read through a few other posts from riders with similar problems but have not found good documentation (pics,video) on what to look for and or steps. Keep an eye out in the next few weeks for posts with pics and video.
 

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Discussion Starter #7
Up and Running

Update: Took a day off work yesterday to pull the alternator cover, inspect the stator and replace the Starter Motor. I put it back together and gave it a little blip to see what happened and Tada! it turned over! It took me a long time to deduce what was happening. So here are my recommendations when your 1998 Ducati 748 won't turn over. Replace old parts. It's worth it.
1. Replace Voltage Regulator = $80
2. Replace Solenoid = $30
3. Replace the Starter Motor = $200
4. Replace both ignition relays under the seat= $70
5. Optional, get a new battery


Thanks for all of the support.
 
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