Ducati.ms - The Ultimate Ducati Forum banner

1997 900 SS/SP STARTING Problem

678 Views 12 Replies 10 Participants Last post by  scrim
I have (had it since new) a 1997 900 SS/SP that has a problem that I'm wondering about...essentially the bike starts right up kinda only when it wants to. The symptoms are (1) battery seems to not keep a charge like it should but lights come on nice and bright and the fuel pump runs when key is turned on. It turns over smartly some times but not regularly enough to trust it, though it seems to do fine when jumped from my truck battery. (hmmmmm!) (2) battery doesn't seem to want to hold a decent charge The only thing I've ever changed in the electrical system is the battery...so there is that! I have had multiple bikes (50?) over the years so I haven't put more than about 14K miles on the Duc, but I have greatly "thinned the herd" so I've started to (try to anyway) ride the old Duc more now than in past years. Only other bike I own is a totally restored 1970 TRIUMPH Bonneville that is parked in the living room.

My first suspect was the battery as it was kinda older, so I bought a new MOTOBATT MB16AU Battery which didn't really help the problem. I thought maybe something in the electrical system was drawing some current for some reason even when the key is off, but that checked out just fine---no key off draw at all. SO...my suspicions are (1) Starter relay (though not strongly suspicious of this); (2) & (3) are kind of a tie...Starter & regulator. First thing I'm wondering before I dig too deeply into the problem is if there is ANY part that has a bad rep for giving up and causing starting problems?? Nothing but the battery has ever been changed and I keep a maintenance charger on that--even the new one.

ANYONE know of anything in the electrical/starting system that has a reputation for going t*ts up and causing starting issues? I'd kinda like to know that before I go digging any deeper or just springing for a new part(s) just because I am "suspicious" of something.

Gimme a little help here!
See less See more
1 - 13 of 13 Posts
Sounds like you might have more than one problem…
Poor performing charging system and maybe a starter motor that is on its way out…

I had a similar problem on my ‘97 ST2 for a while - the stator was on its way out and also the starter motor commutator and brushes were shot.
The stator probs are common with the early ST2, but more usually it’s the regulator / rectifier that goes wrong…

Do a search on here / YouTube for Brad the Bike Boy’s charging system diagnosis.

The starter motor can be stripped in situ to have a look at the brushes & commutator but if you need to change the whole unit it’s a bigger job…

mine off the bike…
See less See more
Easy to verify the bike is charging after you get it started.
This rules in/out the charging system.

Easy to upgrade to larger gauge starter cables and ground.

Easy to verify drain.
Unplug the battery after the ride and see if it still works in the normal down time.

Easy to jump the starter solenoid
Starter spins better it is likely the solenoid.
Starter does not spin look at the starter motor- AFTER verifying battery is good.
Intermittently turning over better or worse has to be an electrical problem - either the starter itself has worn brushes or similar, or one or more of the connections between the starter, battery, and ground is weak.

The stock wiring on these bikes is barely big enough power a fax machine, let alone deliver the power needed crank over a 900cc twin.
Add 25 years of corrosion and you get problems like this.

  • Remove, clean, and retighten the ground connection at the rear of the engine by the crank breather. As well as battery to frame ground.
  • Verify the cable between starter and solenoid is tight on both ends, and make sure the post on the starter itself isn't spun (which breaks the connection to the brushes inside).

If any of that helps at all, you want to consider replacing all that puny low quality wiring with some appropriately sized quality cable. It makes a huge difference and reduces stress on the battery as well. I downsized to a smaller battery after I did it, as the -16 is really overkill if everything else is in good shape. My engine is also 944 and pretty high compression, yet it turns over like nothing now, and starts on the first compression stroke when hot.
See less See more
Ducati starter upgrade - starting upgrade for Ducati motorcycles recommend just replacing the connections that attach to the solenoid and starter. Or at this point it is old enough for a replacing of the stator and R/R. My 900ss had similar issues. Got a Shorai battery, Ricks stator and R/R, motoelectric cables. Starts immediately every time.
Pretty much everyone ends up replacing the battery cables with larger ones, a new solenoid , MOSFET voltage regulator, and a new starter. If they are original, they are really old. Read various posts on starting issues with the Carbies. They will steer you towards the good stuff. None of it is that expensive if you source it from the right place. If you replace the items one at a time you’ll know when you have found the guilty party. One warning : When you replace the cable between solenoid and starter , make sure the post on the starter does not rotate with the nut or you will break the wire inside the starter. Spray it down good with penetrant and tighten the nut UNDER the cable first, then hold that nut as you remove the nut holding the cable. You don’t want to break the starter while you’re trying to fix the problem. It’s probably corroded cables or the solenoid, I’d start with them.
Can I throw in one more, rather stupid thing, just to write it off the list. I once had a similar problem with mine. This was the culprit. It's the main 30-amp fuse. It still has continuity, it's not broken - I don't know how. I now keep it on the desk to amuse myself from time to time during a boring zoom meeting.
See less See more
Everybody seems to have this covered perfectly. The first thing that came to mind is the fact that the starter connection is located in a spot just asking for corrosion.
Thats right ! Good call, I forgot about that. Clean up those connections in the fuse block and put some dielectric grease on them. They can corrode and cause problems.
Hey everybody, I thank you ALL for responding...I just now went out and took the lowers off of it again and will start more seriously chasing this problem tomorrow. Thanks for all the input!
Again, what the others have said! My 93 was very reluctant to crank and I replaced the cables with 6ga. welding cable and 1/4" ring terminals, it practically leaps to life! I ran the ground cable from the battery directly to the lug on the cases where the stock jumper attaches from the footpeg bracket bolt [piggybacked it] and used star washers between the case and the terminals. That alone made a huge difference.
  • Helpful
Reactions: 1
Well...since It's hard to believe that the starter has given up the ghost with less than 14K miles on the bike since new, not to mention that it seems very enthusiastic when hooked up to a known good battery with jumper cables, I'm going to start with upgrading all cables to-from the battery and starter, checking/cleaning all other connections to include the fuzes/fuze block, and installing an MOS/FET regulator. After all that is done see how it works and then consider the solenoid and the starter...likely solenoid first as it is (1) cheaper than a starter and (2) MUCH easier to change out and it could be getting weak just due to age. Next move after all that will likely be checking and possibly replacing the starter.

It sure would be nice to get this thing starting right and being "trustworthy" so it doesn't strand me somewhere along the way. Which usually (Murphy's Law!) happens in the least convenient, worst place!

I really love this old Duc and want to ride it with confidence that all is well with it!

See less See more
Upgrading the starter cables transformed the starting on two 900SS/SL’s I’ve been involved with.

I bought this kit from the UK: ExactUK HiCap Starter Cables for Ducati Motorcycles - Our Product Specifications

But there’s probably similar local for you.
1 - 13 of 13 Posts