Gilera DNA 50 - Starting issue driving me crazy!

Hi all,
I'm hoping someone else has run into this issue with either a DNA or something with the Piaggio 50 2T engine.
I brought the bike last year as a non-runner with the intention of getting ready for my son to ride but it turned into a total rebuild so in the end I got him something else !
I've done a whole load of work, total engine rebuild, crank, bearings, water pump, 70cc kit. I've replaced the CDI stator, starter motor and loads of other bits, some sourced used.
The bike starts and runs off the kick start but just won't even produce a spark when turned over with the starter. I've even tried running the starter directly connected to another battery so it isolated completely from everything else and no joy.
I can spin the motor with a drill in the flywheel nut and it sparks fine and I get over 100VAC on the green wire, when I spin it from the starter I only get about 70VAC.
I'm wondering if the starter just isnt spinning the motor fast enough and maybe that because the motor is still really tight ...that's the best I can come up with !
Anyone else ever run into a similar issue...I'm in way to deep on hours on this thing TBH

 

Is the engine to frame earth good ? You could also try taking rear light bulb out then try electric start.

 

Greetings mate, If you can get over 100VAC with a drill and only about 70 with the starter itself, it sounds like the starter is not getting enough juice from the battery, first i would check the starter relay with a voltmeter,then your voltage regulator, since you have already replaced the stator we can rule that out, or its just a bad ground somewhere

 

Thanks for the response and apologies for not updating the thread.
I finally have this project up and running after way too many hours, it's been emotional
I won't bore you all with the endless fault finding but this one has been one of those classic situations where I introduced lost of other problems trying to fic something.
The intermittent ignition was down to too large gap on, new the pick up coil. For what ever reason the, new (not original part) starter motor just wasn't spinning the engine as fast as the old one, which I refitted in the end but it will need replacing as it was full of water when I originally stripped it down.
Also the brand new engine rebuild was obviously quite tight, now I've run the motor for bit it starts from he starter motor....at last.
I'm on the home stretch on this one now, I even ran it up the road yesterday after fitting new rollers, carb and making some jetting changes. I've just ordered a new exhaust and and a new speedo sensor, that should be the last things I need to make it fully working and get an MOT.
Irony is I'm not all that interested in riding it, I got it for my son but it ended up being such a big project I got him something else !

 

hey man,no worries for not updating us,life is a busy thing and im glad to hear that you got it all sorted out and that it is up and running,always a great feeling when you finally get it running after losing your mind on it,been there too many times