Px200 timing mark advances under revs
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Hooked
vba vespa 210, API monza230
Joined: 15 Oct 2009
Posts: 136
Location: adelaide australia
Tue Dec 18, 2018 1:09 am quote
Hi guys l,
Iím after some advice Iím currently setting up the timing on my latest project
Pinasco cases Malossi mhr 210
I have a Ducati cdi with piaggio stator and the pk flywheel that Iíve machined down to 1500g
The issue i have is at 2000 rpm it strobes at 17deg with is where I want it but if I increase the revs to 4000rpm the timing goes to 24deg+
Iím going to try another timing light tomorrow but if I get the same result is it problem with the cdi? Stator? Or flywheel
TI advance for any advice offered as electrical is my weaknes

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Molto Verboso
1979 P150X, 1983 P200E, 1987 T5, 1996 PX200E, 2011 Yamaha Fazer 600 S2
Joined: 02 Aug 2015
Posts: 1306
Location: Veria, Greece
Tue Dec 18, 2018 2:29 am quote
Have you also machined the flywheel's key slot to fit the P's ignition?? The PK's key slot is at a different position so the pick up trigger "fires" at different degrees...
Hooked
PX 150
Joined: 15 Sep 2006
Posts: 451
Location: Gold Coast, Australia
Tue Dec 18, 2018 2:48 am quote
SaFiS wrote:
Have you also machined the flywheel's key slot to fit the P's ignition?? The PK's key slot is at a different position so the pick up trigger "fires" at different degrees...
Safis it makes sense what your saying.
But itís totally irrelevant to the issue this guys having.
Hooked
vba vespa 210, API monza230
Joined: 15 Oct 2009
Posts: 136
Location: adelaide australia
Tue Dec 18, 2018 2:58 am quote
Yes mate ,the pk flywheel I have is the one with the extra key way cut in and it is installed on the correct key way slot
Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 1032
Location: London UK
Tue Dec 18, 2018 3:55 am quote
Hmmm......as well as the keyway difference between the PK and PX isnít there a 4 mm in-out difference on the pick up too? Maybe its that.
Ossessionato
1980 P200E, 1974 Primavera, 04 Ninja 250
Joined: 04 Apr 2013
Posts: 3604
Location: San Diego, CA
Tue Dec 18, 2018 9:04 am quote
I had a BGM stator on a lambretta do the same - most guesses at the time were the pickup was bad. I solved it by going back to points, but I'd look at the pickup for sure.
Hooked
vba vespa 210, API monza230
Joined: 15 Oct 2009
Posts: 136
Location: adelaide australia
Tue Dec 18, 2018 11:50 am quote
Jack221 wrote:
Hmmm......as well as the keyway difference between the PK and PX isnít there a 4 mm in-out difference on the pick up too? Maybe its that.
Ah yes Iíll check that also thanks
Molto Verboso
1979 P150X, 1983 P200E, 1987 T5, 1996 PX200E, 2011 Yamaha Fazer 600 S2
Joined: 02 Aug 2015
Posts: 1306
Location: Veria, Greece
Tue Dec 18, 2018 1:42 pm quote
jimscoot wrote:
Safis it makes sense what your saying.
But itís totally irrelevant to the issue this guys having.
I understand what problem he's having
I had a scooter with the wrong flywheel, behave just like that, that's why I asked for the key's position. Also, as John suggested, a bad pickup could be doing the same...
Hooked
vba vespa 210, API monza230
Joined: 15 Oct 2009
Posts: 136
Location: adelaide australia
Tue Dec 18, 2018 3:08 pm quote
Thanks for the replyís and suggestions this now gives me some things to check and see if they rectify the ussue
Hooked
vba vespa 210, API monza230
Joined: 15 Oct 2009
Posts: 136
Location: adelaide australia
Tue Dec 18, 2018 11:52 pm quote
So this afternoon I tried a different timing light same result
Tried packing up stator by 4mm
Same result
Iím thinking the stator is the problem but donít have a spare to try
Molto Verboso
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 1032
Location: London UK
Wed Dec 19, 2018 2:30 am quote
If you have a PX flywheel, you could try that.
Hooked
vba vespa 210, API monza230
Joined: 15 Oct 2009
Posts: 136
Location: adelaide australia
Wed Dec 19, 2018 3:15 am quote
I donít have a px flywheel to try
Iíll probably order the sip vape and change the lot
Enthusiast
PX125E
Joined: 06 Oct 2018
Posts: 58
Location: Gravesend, Kent, UK
Thu Dec 20, 2018 4:19 pm quote
Timing problem
Hello.
I can only advise what happened to me. I have a 2012 PX125E.
It had strange problems to say the least. But to jump to the last chapter in the book of madness. I checked the timing yet again and discovered the flywheel moved due to the main bearing on the flywheel side was a dick fit.

Give the flywheel a firm shove at the top and sides. Mine moved and the rocking motion could be heard and felt. It would start second kick every time at the time.
Hooked
vba vespa 210, API monza230
Joined: 15 Oct 2009
Posts: 136
Location: adelaide australia
Thu Dec 20, 2018 5:36 pm quote
worrywort wrote:
Hello.
I can only advise what happened to me. I have a 2012 PX125E.
It had strange problems to say the least. But to jump to the last chapter in the book of madness. I checked the timing yet again and discovered the flywheel moved due to the main bearing on the flywheel side was a dick fit.

Give the flywheel a firm shove at the top and sides. Mine moved and the rocking motion could be heard
and felt. It would start second kick every time at the time.
Thanks for the advice but mine are band new cases, bearings etc etc
Hooked
Jet 200, P200E (x2), T5
Joined: 27 Jan 2013
Posts: 300
Location: Paris, France & L.A., Cal, USA
Fri Dec 28, 2018 3:16 am quote
Check anyway. Pinasco casings can have bearing positions badly machined. Bearings can be crap from new as well.
Other than that, I'd concentrate on the CDI/pickup side of things, as that would be an obvious source of wonky ignition timing.
Molto Verboso
Kymco Downtown 300i ABS
Joined: 09 Feb 2008
Posts: 1040
Location: UK
Sat Dec 29, 2018 1:07 am quote
Are you sure that there is no electronic advance built in to the CDI unit? That would not be unusual.
Member
Stella
Joined: 28 Jan 2012
Posts: 16
Location: USA
Sat Dec 29, 2018 8:45 am quote
2 strokes generally don't use an advance. I've never seen a 2 stroke that had one.
Hooked
vba vespa 210, API monza230
Joined: 15 Oct 2009
Posts: 136
Location: adelaide australia
Sat Dec 29, 2018 2:19 pm quote
Frank N. Stein wrote:
Check anyway. Pinasco casings can have bearing positions badly machined. Bearings can be crap from new as well.
Other than that, I'd concentrate on the CDI/pickup side of things, as that would be an obvious source of wonky ignition timing.
I did swap over the cdi but I still had the same problem but I didnít have a spare stator to test so Ifitted the sip vape ignition now and am going to have the piaggio stator checked via a local scooterist who is a electrical guru and keep as a back up for my other Vespa
Molto Verboso
2005 PX150 In a Love-Hate Relationship with a 2-Stroke Vespa Since 2007
Joined: 01 Sep 2007
Posts: 1763

Sun Dec 30, 2018 6:45 pm quote
I believe this was discussed somewhere, maybe the old Stella Speed forum. The standard CDI is basically wrong at lower rpms. At idle rpms itís retarded. As rpms increase toward 2500-3000, it advances and from there on out pretty much stays the same.

The later PX150 Service Manual specifies that the timing should be checked at 3000 rpms. This alone suggests that timing measurements below that should not to be used.
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