Humor me here please, because there's a lot going on at once... Bike is a carby M600.
I've been having symptoms that made me suspect vapor lock (and other clues that led me to this hypothesis, but more on that later). The bike sputtered and died in busy traffic, and I was lucky enough to cross 3 lanes before rolling to a stop. After a few moments the bike fired up again, but the starter was laboring to turn the motor over. Got within a mile of home, happened again only this time no go. Would barely turn 3/4 of a revolution. Assumed my Chinese battery was junk, pushed it the last mile home (which sucked). Installed a brand new fully charged Antigravity. To make sure I wasn't hydrolocked I Pulled both spark plugs before cranking again - abracadabra, the starter spins the crank over... Except, not as fast and strong as I'd have liked. The old "finger in the spark plug hole" method of compression testing was unimpressive, it didn't blow me away (get it? Har Har).
All this babbling is to ask - can a bad starter be just bad enough to not be able to overcome the motors compression? But good enough to spin with the spark plugs removed?
Also want to add that when cranking the bike with the plugs removed and grounded, everything sounds healthy... No metal on metal/grinding/loose parts clanking etc. Flywheel, belts, rods and pistons seem fine. And as for hydrolock - no gas, oil, or other fluid spurted out of the holes, and the plugs are a decent looking mocha color. The crankcase is not overfilled, and there is no smell of gas in the oil. The mechanical fuel pump also checks out OK.
I've just never heard of a Ducati starter failing in such a way (where it's "weak"). Usually they either do nothing, or work intermittently.
I have triple checked my power cables from the battery to solenoid, solenoid to starter, and I have a big beefy 4g ground strap from a lug on the motor directly to the negative terminal. This setup has always spun the engine up fast and strong.
I also suspect I have an excessive amount of crankcase pressure, but I'll get into that after I determine whether or not I need a new starter.
Sorry for the rambling post... I guess I was hoping there was something else I could investigate while waiting for my eBay starter to arrive.
Thx...
Yes, it is possible, but rare. Shorted armature could cause this. Or a really bad bushing. Before going any further try jumping it with a known good battery. A lithium battery that went flat while in storage could be permanently damaged.
You also want to confirm the starter circuit is in good order. This is done by testing for voltage drop caused by high resistance in connections or a component, in this case, starter solenoid. Don't forget the ground side.This video is for a car, but same thing and it saves a lot of typing. Easy shade tree method - known good battery to positive on the starter positive and ground directly to the starter body with suitably sized cables. The bike must be in neutral since you are bypassing everything.
After you get the bike running check charging system performance, as it could have been your stalling problem.
Oh, fully charge that "junk" Chinese battery and have it load tested. It might be good. Never ass u me.
Thanks Howie
This would be the 3rd battery I'm on (decent customer support, sketchy product - there are 2 in my bin, one stuck at 3 volts the other too dead to register, neither accept a charge). According to my multimeter and my Optimate charger/tester/maintainer, the current battery is OK tho. Swapping in a known good battery yielded the same results.
Several months ago after my second battery failure, I followed the method posted on the Electrosport website to test the charging system with a quality multimeter (after installing the fully charged replacement). Obviously I can't do it again properly since the bike won't start, but at the time everything checked out (the voltage output of both the stator and RR, at idle and while revving). I've also thoroughly checked the power and ground wiring (both have been upgraded as well). There *could* be a potential flaw somewhere in the stator > RR and RR > battery wires, but that wouldn't explain why a known good battery wouldn't at least temporarily solve the issue.
I will bypass the solenoid and apply power directly to the starter today, thanks, I feel silly for not having thought to do that already.
If we briefly assume the battery, charging components and starter are all OK - what else could be preventing the motor from turning over with the plugs in? I tried starting it with one plug in each cylinder but no luck, it'll give a little extra "chuff", but will not spin at all unless *both* plugs are removed. I'm a little concerned about forcing the issue and making my problems worse. There's no sign of water or fuel in the crankcase but I'll be draining and changing the oil today regardless.
Thank you for taking the time to address my post, Howie.
If you remove the spark plugs and turn the engine by hand how does it feel? No tool, on a rear stand turn the engine engine by the rear wheel in gear.
In theory the starter can be bench tested, the problem is no published specs I know of so all you can do is apply battery voltage and hear how it sounds.
Quote from: howie on October 16, 2017, 05:16:47 AM
If you remove the spark plugs and turn the engine by hand how does it feel? No tool, on a rear stand turn the engine engine by the rear wheel in gear.
In theory the starter can be bench tested, the problem is no published specs I know of so all you can do is apply battery voltage and hear how it sounds.
I just moved out if a house with a garage and into an apartment so I've been shuttling back and forth for tools. Pain in the arse. I'll grab my Pitbull stand today and turn it via the rear wheel.
I'm very worried this is something serious and expensive. All of the anecdotes I find when googling this problem are either bad starter or hydrolocking. But there's no sign of the latter, no gas shooting out the holes. I mentioned in my OP I suspected excessive crankcase pressure because after a ride a couple weeks ago I discovered a good amount of oil leaking from both the breather and the forward valve cover, despite both being well sealed. I don't wanna let my mind run wild before I rule out the starter and charging system, but this is very, very concerning. I keep telling myself if a rod or valve was bent or broken, the engine wouldn't turn at all, or at the very least I'd hear obviously alarming sounds if it did, but I'm sure that's not necessarily the case.
How's the oil level?
Quote from: ducpainter on October 16, 2017, 05:32:22 AM
How's the oil level?
Exactly in between the bottom of the sight glass and the line of the sight glass, that's with the bike directly upright. I've always been fanatical about oil levels, I check to be sure they're neither too high or too low prior to every 3-4 rides.
Quote from: LowercaseJake on October 16, 2017, 05:36:58 AM
Exactly in between the bottom of the sight glass and the line of the sight glass, that's with the bike directly upright. I've always been fanatical about oil levels, I check to be sure they're neither too high or too low prior to every 3-4 rides.
Then it isn't hydro-locked.
Check all the grounds like howie suggested, and put voltage direct to the battery.
things I want to reiterate - A: with both plugs out, the starter spins the engine steadily, but compression is extremely low using the crude finger test. However, it feels the same in both cylinders. B: the engine *does* turn with the plugs in, it just labors to do so... I can hear it struggle getting through each full revolution before pausing to give it a break. Again no alarming sound of broken parts... The symptoms are 100% identical to that of trying to start a car or bike with a weak or dying battery. Except I've now tried 3 different batteries, all fully charged with a reliable charger. I won't have the means to bypass the solenoid or turn it by hand till I can get to my garage later today.
Quote from: ducpainter on October 16, 2017, 05:39:25 AM
Then it isn't hydro-locked.
Check all the grounds like howie suggested, and put voltage direct to the battery.
Ducpainter - how do you know it isn't hydrolocked by the oil level? Or are you saying that because I've never over filled the crankcase? In theory, if something was causing excessive crankcase pressure, this could have theoretically forced oil into the cylinders, causing hydrolock? Again not trying to get ahead of myself here, I'm just agonizing a bit since I can't bypass the solenoid or turn the motor by hand right at this moment.
Most engines hydro lock due to overfilled cases...usually fuel, not from liquid in the cylinders. It takes a lot of liquid to lock up a motor. The amount forced in by excessive crankcase pressure would most likely just burn. Your oil level isn't low, which indicates crankcase pressure isn't pushing it anywhere.
You've had the plugs out, and didn't mention them being soaking wet, so I'm saying your issue isn't mechanical, but electrical. Again, it takes a lot of liquid to lock up a motor.
Of course you're closer, and my crystal ball has limited range these days, so I could be mistaken. My experience tells me that your issue is likely very simple.
You'll feel better if you stop imagining everything that 'could' be wrong, and wait until you can diagnose the problem.
Points well taken Ducpainter.
Confirmed the following are fine: solenoid/switch. Power and ground wiring. Battery. Motor turns by hand via the rear wheel, in all gears, with no noticeable scary sounds.
A few months ago while the bike was on my old lift, I attempted to start it - thumbing the button produced only rapid whirring sound. Bypassed the switch and same result. I'd heard that a weak/worn starter could have "dead spots", where the brushes were worn. Since this was a newer Rick's starter I thought it to be a bit flukey, so I pushed the bike back and forth a few times, clicked up and down through the gears, afterwards the bike fired right up.
Well, last night as I was troubleshooting it happened again as I was testing/cranking, testing/cranking. . I think it's obvious I have a bum starter, and the current situation has hastened its demise. Best way to describe the sound coming from the starter is a radio controlled toy revving/whirring.
Now if you guys would humor me once more:
I already explained I'd been experiencing issues with sputtering / stalling that I'd written off as heat soaked fuel hoses.
Now, each time the bike died it would start up relatively easy almost immediately afterwards. This time, during a 3 mile ride from A to B it stalled 3 times, becoming more and more difficult to crank/ start each time until it finally would barely crank at all then of course not start. And, I was getting a flickering oil pressure light at traffic lights which would go away with a gentle twist of the throttle.
Also, remember how I've now gone through 2 lifepo4 batteries which I originally attributed to being "cheapo Chinese batteries". Plot thickens.
Pull the left cover and investigate the stator? I do have a spare OEM stator in excellent condition. And what's in there is an aftermarket Electrosport.
As a reminder I've thoroughly investigated the power and ground wiring, the health of the battery, confirmed I'm getting fuel/spark, turned the motor over by hand, and also attempted to bump start the bike, which didn't even come close to working.
That spinning noise you hear is a bad sprag, not the starter The sprag is not allowing the starter to turn the engine, therefore the radio controlled toy revving/whirring.
With all the problems you are having maybe it is time for professional help.
Quote from: howie on October 17, 2017, 05:39:40 AM
That spinning noise you hear is a bad sprag, not the starter The sprag is not allowing the starter to turn the engine, therefore the radio controlled toy revving/whirring.
With all the problems you are having maybe it is time for professional help.
I'd add that changing parts is not an effective method of diagnosis. Why change a stator without knowing it's faulty? Have you put a meter on the battery, or the leads from the stator to determine whether it's charging?
Check the hoses under the tank to make sure you didn't kink the vent after looking around under there. That could explain the sudden stalling issue.
Quote from: howie on October 17, 2017, 05:39:40 AM
That spinning noise you hear is a bad sprag, not the starter The sprag is not allowing the starter to turn the engine, therefore the radio controlled toy revving/whirring.
With all the problems you are having maybe it is time for professional help.
LOL, I don't blame you for saying this. Unfortunately I need to ride or die (no pun intended) on my own efforts.
Thanks for clearing up the issue with the sprag gear, that saves me a lot of frustration Howie. I have a light flywheel and a light clutch basket - professionally installed - could the lack of weight be mimicking a bad sprag? Especially since it's intermittent?
You're correct about impulsively changing parts. I certainly would've inspected the stator before simply installing a new one, but the starter motor was something I was ready to assume was faulty.
I don't think I need professional help, I just need to get *some* of these issues solved so the entirety of these issues is less overwhelming. I do appreciate the help from both of you.
Well guys I received my eBay replacement sprag which came still installed on the oem flywheel. Decided I'd ditch the light FW while I was in there to see how I'd like it. That was most definitely the issue - the old sprag had several rollers that were scored and compromised, and the spring was toast. Starter now turns the motor over properly. As for my other issues - one of my fuel hoses looked like it was getting pinched due to my circuitous routing job, and the breather was only hand tight. Redid the fuel plumbing, replaced the breather crush gasket and tightened. Only thing I'm a little lost on is getting the orientation of the FW right. There's a dot on the crank that I made sure was in alignment with the dot on the FW. With the thrust washer and clutch gear/cog in place the dot is hidden, so I marked the crank to be sure. I also went back over all my ground and power wires, added another washer to the starter nut to be get it nice and tight and filed off the paint at the engine ground lug. Only thing I'm not 100% comfortable with is did I get the orientation of the FW right. I guess I need to get my hands on a shop manual. Appreciate your assistance.
From what you say you should be good with the flywheel. You did either use a new flywheel nut or aftermarket replacement* and torqued it down to 189 Nm. I hope. Loose flywheels are not good.
Though unusual if the sprag is bad enough it can jam the starter.
Keep us posted!
* Like this one that is no longer available https://motowheels.com/search.html?q=flywheel+nut&go=Go or this one https://ccrma.stanford.edu/~peer/Nichols/flywheelNuts.html
Howie, I have a single phase motor, I don't think those jamb style nuts apply to my setup.
Question: if done correctly, should the lump on the flywheel align above the rear most (to the right, facing the engine) pickup? Theres a dot two teeth down from the keyway that I aligned with a dot next to the dogs of the outer face of the flywheel. I'll see if I can post a link to a photo.
I'm dumb, it needed to line up with the keyway. No idea what the dimple behind on the small crankshaft gear is for but the bike fired right up and runs great. Can't ride it yet because the seal on my Ducabike slave popped out and I can't find it, smdh. Thanks dudes.
So, the crank is frozen tight. No idea what I could've done wrong, unless the poor running I described was a prequel to things going awry. I will say that when I replaced the sprag, everything spun over fine, pistons valves and all. I'm wondering If I overdid that...cranking the motor with the cases removed and no oil. I didn't think a couple revolutions would be a big deal but I could've thought wrong.
It's odd to me that the crank won't budge a single mm. Ive removed everything I needed to remove from both sides of the engine (a couple primaries and the oil pump.) to gain visual access to the main bearings. The main crank bearings look perfect, there is zero play in the crank. I theres a necessary keyway slot I'm missing I can def check on that. Just seems odd the motor would abruptly die after 3 seconds, all 3 of which nothing was grinding or slapping. Just simply stopped, and now the crank is frozen.There's not an excessive amount of slag on the oil screen or in the oil. Only thing left to do is remove the heads and barrels to gain access to the rods and pistons, see pif a piston threw a bearing and froze up in the cylinder. If the bottom end is ok, new pistons/rings aren't a *total* disaster. And I suppose I could find a used bottom end if absolutely necessary, but its unfortunate bc I had this engine rebuilt from the bare cases up.
Double check your cambelt pulleys for correct timing. Check all the gear teeth where they mesh as you were just in there.
Cam timing is spot on. 2 piece adjustable hubs were added last year and dialed in. Belts show no signs of jumping a tooth and the valve train operates as it should. Pistons are froze at the bottom of the stroke.
Any luck finding it ?
Quote from: koko64 on October 31, 2017, 12:19:07 PM
Any luck finding it ?
I don't have a very long fuse so I've already begun parting out the motor in disgust. I've already received a decent chunk of my investment back selling the Nichols flywheel, V2 heads are spoken for, vented clutch side engine case cover, a really pretty polished stator cover etc. The tool I ordered for removing the cyl head nuts arrives tomorrow, so I may have an idea what happened then. If the crank operates on a keyway as Speeddog said that "key" may have worked itself loose, who knows. There's some gold slag on my sump screen which could be normal or it could be bearing shells. Who the F knows.
In all honesty, I never had as much fun on this bike as I did on my old 750, and when I borrowed an S2R800 for a week I didn't wanna give it back. The 900 felt "lazy" in comparison to both engines IMHO.
Thx f' asking tho, Koko.
You did align this
(http://www.mad-ducati.com/Technical/Engine/FlywheelDot_M.jpg)
?
Quote from: greenmonster on November 01, 2017, 07:49:10 AM
You did align this
(http://www.mad-ducati.com/Technical/Engine/FlywheelDot_M.jpg)
?
No, not initially. I aligned it with a dot on the gear which was wrong. Is that why my motor is dead? I figured at the worst case scenario my ignition timing would be wack.
Agree w ignition timing should be the main issue.
If too off, doubt it would start. Yours did.
Removed heads yet?