Told this one before, the very old Autosparky tested my starter motor by holding the drive sprocket hard against a pine, softwood post, holding the motor in his hands off the bike, holding his roof up and energising the starter motor, it then worked like a router and chopped a corner of the post away. That was his test for loading it to see if it held power and didn't stall under load. Take care doing this, it can bite.
Slow cranking
- Thread starter townsend846
- Start date
motoddrob
Hero member
- Location
- S/W Australia
Been using Lithium for the last 8 years. The BM is still cranking strong after 8 years. The Motodd is on it's 2nd Lithium, the first was too small like 220 cca and it eventually failed. Replaced with a bigger one 420cca and has been good so far except this morning went I turned the key on and nothing, not even the led neutral light. The on board battery push button digital voltage display wouldn't even activate when pressed!!. My meter said it had 11.9 volts.Well, wet cell batteries anyway. AGMs are pretty good
Jumped started it from the BM, ran for it a while, turned it off, 12.2v went to restart, blup and then a dead battery again, not even the neutral light again. When I had it running the RR was fluctuating between 12.2 and 12.7vat 3-4000 rev. I'm getting suss about the new version of the SSB lithium batteries. They seem to have like a cut out switch in them. Thinking a new RR and a AGM battery might be the go.
Andy
Hero member
- Location
- Auckland, roughly
We use a lot of Li in emergency lighting, it’s much more robust with irregular charge cycles so should be good for vehicles (with specific charging), but we find it can also fail badly without warning.
Unlike an old wet lead-acid that gives you plenty of warning (if you listen…
)
Unlike an old wet lead-acid that gives you plenty of warning (if you listen…
)
Last edited:
Schurminater
Hero member
- Location
- Surrey Hills
Is that low, my new one is 300?……..don’t you just love electrical mysteries
……hope you get to the bottom of it soon.
townsend846
Full member
- Location
- London&essex
Attachments
townsend846
Full member
- Location
- London&essex
I’m getting a bit low in the phalanges department but like the idea
townsend846
Full member
- Location
- London&essex
I have one on my mk1 lemans and it’s fine even with a highly tuned motor so though it would be fine for the lavvy
Most probably the field windings will look like those in the pic. As Cam has described, most current simply flowing into the casing instead of powering the field coils. It's not only the insulation between coil and casing, the winding insulation is usually no longer existant, re-insulating is rather difficult. Armatures rarely give up, most are fine with a clean-up of the commutator and a thorough de-rusting. I can supply NOS field coil sets.
piet
piet
townsend846
Full member
- Location
- London&essex
Thanks ,if I need them I’ll be sure to ask ,didn’t remove field coil’s they looked ok but without removing it’s hard to say ,do you have a brush set ? And if not are they available from anyone in the uk.and after speaking with cam he said you’re the man to speak to about dmc 1 advance curves , I have a 1977 so I’m told jotaised motor 10.1 pistons 4c cam 32mm delautos and am fumbling through the 8 curves that are available,so far I’ve tried 2 4 and am currently on 7
I'd stick to a curve topping at 30-32° BTDC. Steep or shallow is dependant on your riding preferences, the steeper the advance curve, the more aggressive the engine reacts. Need to keep an ear open for pinking though (might need Champion N2 or NGK9). Be sure to set the ignition up on curve #1, ie 32° full advance. Also, check the flywheel markings are accurate. Actually, you can disregard the stock TDC marking, you need a 32° BTDC mark, if it hasn't already been done. From there, it's flicking the switches.
Edit;
Looking at the curves from your previous post, I'm not sure that they are for a Laverda triple. Triple curves were generally 32° and less full advance, more than 32° would be for very low-comp motors. These curves are mostly more than 32°, Moto Guzzi maybe. I should have a DMC I manual for a triple... somewhere. See if I can dig it up this weekend. DMC I units were made for all Laverda models, as well as quite a few other marques. They were quite popular in the Guzzi crowd, a fair few were made for bevel and belt Ducatis as a replacement for the OE Bosch units. They can also be found in XS650 Yamahas, H-D Sportsters, Honda 4, Benelli 4 and 6, etc, etc, just about any old banger that originally ran points. Your dip switch settings will be the same as the curves shown, ie, setting #1 equals curve #1.
I can supply individual brushes, but the leads came out a bit short, thankfully only at one end. The brushes fit nicely and are of the correct grade, just a pita to install in the brush holder. I could offer an overhaul, but thanks to Brexit, that's no longer possible.
piet
Edit;
Looking at the curves from your previous post, I'm not sure that they are for a Laverda triple. Triple curves were generally 32° and less full advance, more than 32° would be for very low-comp motors. These curves are mostly more than 32°, Moto Guzzi maybe. I should have a DMC I manual for a triple... somewhere. See if I can dig it up this weekend. DMC I units were made for all Laverda models, as well as quite a few other marques. They were quite popular in the Guzzi crowd, a fair few were made for bevel and belt Ducatis as a replacement for the OE Bosch units. They can also be found in XS650 Yamahas, H-D Sportsters, Honda 4, Benelli 4 and 6, etc, etc, just about any old banger that originally ran points. Your dip switch settings will be the same as the curves shown, ie, setting #1 equals curve #1.
I can supply individual brushes, but the leads came out a bit short, thankfully only at one end.
The brushes fit nicely and are of the correct grade, just a pita to install in the brush holder. I could offer an overhaul, but thanks to Brexit, that's no longer possible.piet
Last edited:
townsend846
Full member
- Location
- London&essex
Thanks for your valuable advice, and will put a 32 degrees mark up and check from there , running b9ev’s in it and even at 36 deg no pinking , but need to check stator marks to confirm what they areI'd stick to a curve topping at 30-32° BTDC. Steep or shallow is dependant on your riding preferences, the steeper the advance curve, the more aggressive the engine reacts. Need to keep an ear open for pinking though (might need Champion N2 or NGK9). Be sure to set the ignition up on curve #1, ie 32° full advance. Also, check the flywheel markings are accurate. Actually, you can disregard the stock TDC marking, you need a 32° BTDC mark, if it hasn't already been done. From there, it's flicking the switches.
I can supply individual brushes, but the leads came out a bit short, thankfully only at one end.
piet
Dellortoman
Hero member
- Location
- Tasmania, Australia
Is there a reason you've chosen B9EV (gold/palladium electrode) spark plugs? The normal spec plug for our old bikes is B8ES or perhaps B9ES if you're racing, with the standard 2.5mm copper core. I've not tried anything fancy like gold or iridium plugs. Just wondering if they offer any advantage. I presume they cost a lot more than the bog standard plug.
Not that this has anything to do with your slow cranking problem.
Not that this has anything to do with your slow cranking problem.
Andy
Hero member
- Location
- Auckland, roughly
That must make life very difficult in this digital age
townsend846
Full member
- Location
- London&essex
They came with the bike cam and I put new ngk b8es in and after a month it fluffed the left hand plug ,checked valve clearance’s all good replaced again with another 8 and it did it on centre plug ,put the 9ev’s in and it’s been fine until this slow cranking bollocks
Well, that makes no sense, NDK plugs get colder as the numbers get larger. An 8 should foul easier than a 7 and a 9 should foul easier than an 8. If all is well a B8es should self-clean. One important thing is to start with full choke and turn the choke off as soon as you possibly can, they will foul if the choke stays on for any longer than you bearly need it. Just for shit and giggles try tapping the starter with a solid lump of wood as you press the button, that might suggest a fix if it works and is easy to try.
CLEMTOG
Hero member
I don't know if it been said before because I haven't read the whole thread when it got a bit lost but here is something that I have found, the brushes? they may well look good and could even be at about the "half worn down" stage and should have plenty of life left in them, if the brushes have been replaced, then it is necessary to solder the braided cable to its post inside the starter, when new this is (hopefully) done well, but I have seen two starters that have had the brushes replaced and failed after not very long, this was due to much too much heat being applied when soldering the braid and it fused a large section of it, flooded with solder by capillary action, and so hardening it, removing a good portion of the braids flexibility, which is why it is braid, this caused the spring to fail to give those replaced brushes good contact, one was done by me (oops) and the other by a professional electric motor re-winder, take a look and see
CLEM
CLEM
Davo
Senior member
- Location
- West of the Rabbit Proof Fence
I have a SSB Lithium sitting with the distributor now being tested as it failed after 5 months. Would not start the bike, Showed 7 volts on the meter, and when I whacked it on the smart charger would only be recognised as a 6 volt battery. The older one I have is still going strong at 8 years. Battery was always disconnected from the bike so was not discharging.
Davo
Senior member
- Location
- West of the Rabbit Proof Fence
The one in my Laverda is fine, no longer has Bosch igntion but. Turns it over like a top. The failed battery was in my Sprint, and as I say, disconnected between rides. These things will sit on a shelf for 2 to 3 years and not drop charge. Just a dud battery.