avanti problem

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gp200ts1
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Posts: 79
Joined: Sun Oct 09, 2011 1:47 am
Main scooter: lambretta series 2
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every now and then the scoot seems to die off and will not rev (feels like its running out of fuel), it backfires once then takes off again as if nothings wrong. i've cleaned the breathing sweet filter as it was a bit dusty and checked the tank vent and tap and the readings on the cdi check out ok.
i'm stumped!
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drunkmunkey6969
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Joined: Sun Jan 04, 2009 1:42 pm
Main scooter: '69 Lambretta GP
Location: North Yorkshire
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When you say you've checked the fuel tap....do you mean you've measured fuel flow? If so, how much does it flow per minute? Also....what size float valve have you got in your carb? If its a 200 swap to a 300.

As far as ignition goes....you say the cdi readings check out.....do you mean Stator readings? And have you strobed the timing? You'll often find that any faults or weaknesses show up when under load.....so the strobe is fine at tickover but then erratic at medium/high revs.....this then gives you a clue as to the problem.

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OAP
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Paul,
Did one on Saturday, same problem, Stator braking down, check for low reading.

It ran exactly as you have stated before.
gp200ts1
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Posts: 79
Joined: Sun Oct 09, 2011 1:47 am
Main scooter: lambretta series 2
Contact:

Thanks Ron, i'll change the stator tonight and see how it goes
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Terrible Taff
Dealer
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Main scooter: Lambretta's & Vespa's
Location: 21 Meyricks, Coed Eva, Cwmbran, Torfaen, NP44 6TU
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Hi Paul

Sorry to hear your having teething problems with your new engine set up.

Have you check also the plug gap? I used 0.020" max.
New NGK plugs come set at 0.028" hence misfires when used for a while & carboned up.
However the DL150/200 owner's manuals say use 0.016" to 0.018".
Next check the CDi unit earth wire for a good conection.
I have also come across an internal break in the earth wire! Check by trying to stretch the outer wire casing between your thumb & finger.

If you wish & have time to come up to Newport one day we could run it up on the rolling road & check it all through & the jetting etc.

Best regards
Ian @ Taffspeed
07794 003276
Ian T Frankland

Taffspeed Design Innovations
Mob: 07971 818693
Email: [email protected]
gp200ts1
registered user
Posts: 79
Joined: Sun Oct 09, 2011 1:47 am
Main scooter: lambretta series 2
Contact:

thanks for the invite Ian, might give you a call in the next week or so and arrange something. sorted the problem in the end by replacing the stator with a new bgm one. fingers crossed it will be ok now
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