Vespa cdi failure ?

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Soulstylist
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My scooter is miss-firing intermittently ..
I have rewired any loose connections as needed and checked & cleaned carb,
changed plug, suppresser cap & ht-lead,
I have narrowed it down to two possibilities in line ignition or cdi unit..
when the cdi is on its way out does it start running erratically ?
ie ..as if it's not firing consistently with almost like a lack of power mid way through with the revs cutting in and out ?
ps it's a ducati cdi that's fitted (4 pin type)

cheers for any help
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coaster
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In my personal experience, CDI's tend to just die but LT coils can and do give erratic symptoms. Get hold of a test meter and check the resistance to earth values on the LT coil (green) and Pickup (red). I THINK the Vespa readings are similar to Lambretta ones so you need to see around 430 ohms or better on the LT Coil and 95-115 on the pickup.
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Soulstylist
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thanks for that
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Daggs
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Soulstylist wrote:My scooter is miss-firing intermittently ..
I have rewired any loose connections as needed and checked & cleaned carb,
changed plug, suppresser cap & ht-lead,
I have narrowed it down to two possibilities in line ignition or cdi unit..
when the cdi is on its way out does it start running erratically ?
ie ..as if it's not firing consistently with almost like a lack of power mid way through with the revs cutting in and out ?
ps it's a ducati cdi that's fitted (4 pin type)

cheers for any help
A CDi on one of my lambrettas did exactly that. (and it's a quick and easy change to try, before the LT coil)
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Soulstylist
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Posts: 40
Joined: Sun Aug 23, 2009 10:06 am
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Daggs wrote:
Soulstylist wrote:My scooter is miss-firing intermittently ..
I have rewired any loose connections as needed and checked & cleaned carb,
changed plug, suppresser cap & ht-lead,
I have narrowed it down to two possibilities in line ignition or cdi unit..
when the cdi is on its way out does it start running erratically ?
ie ..as if it's not firing consistently with almost like a lack of power mid way through with the revs cutting in and out ?
ps it's a ducati cdi that's fitted (4 pin type)

cheers for any help
A CDi on one of my lambrettas did exactly that. (and it's a quick and easy change to try, before the LT coil)
Cheers guys tried and replaced cdi..defo not that, I am now going to try the LT coil ,,,,
The Kids Are Screaming For That James Brown Style.......
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