Scooter not picking up properly ........... HELP!

[alanscottj]

Ok, I have been trying to solve a little issue on my scooter for a few weeks now and have reached a point that I just can't get past. The issue is that the scooter nearly dies as I try to pull away - sometimes I have to slip the clutch a touch to get it to rev properly and pull away (once she goes, she flies!). Initially I thought it was jetting as that is what it feels like - like it's not getting enough fuel or it is too rich - but after a week or so faffing with jetting I took her to PSL and got her on the dyno. Amazingly, I had got the jetting spot on (thanks to Facebook help!) - the dyno operator tried for nearly two hours to sort the issue - he went both up and down on pilot, tried playing with air screw mix etc but couldn't fix the issue, it just dies on pulling away. There was a backfire whilst doing the dyno so we thought it might be electrical and gave up there. On the way home from Liverpool I called in at Flintshire Scooter Centre and bought a new CDI and they tested my stator and it gave excellent readings. Fitted new Cdi and the problem is still there. Once the scooter goes she goes perfect, it is just the initial pulling away that is the issue. This afternoon I thought I would check the timing just to rule that out - static timing bang on 18 and doesn't budge at all when I rev the engine. The engine spec is as follows:

Mugello 186 - no porting or anything
60x110 crank with 3mm packer plate
Anthony Tambs external pick up - set at 18 degrees
JL4 Exhaust
Dellorto 30mm carb - set up on dyno with 123 main, AV266, X7 top clip, 40 Slide, 60 pilot
AF cassette clutch
AF 5 speed box with 47x18

Any thoughts? Many thanks!

Scott

[Scooterdude]

My guess would be a failing lt coil or pick up. Remember if you test the lt coil it probably will read ok as you are actually testing the two resistors within the coil and not the coil itself.

[GeorgeS]

Would a quick test be to swap to the stator pickup? 1 wire change and it might show a different behaviour.

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[alanscottj]

My guess would be a failing lt coil or pick up. Remember if you test the lt coil it probably will read ok as you are actually testing the two resistors within the coil and not the coil itself.

Thank you Scooterdude

[alanscottj]

Would a quick test be to swap to the stator pickup? 1 wire change and it might show a different behaviour.

Sent from my SM-G920F using Tapatalk

You mean plug in the red from the stator - bypassing the external pick up?

[garry inglis]

I've just had a bgm stator that showed correct ohms and my sip Speedo wouldn't work till 3000rpm swapped stator and worked straight away so tested the bgm again still showing ohms as it should be but something was breaking down

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[GeorgeS]

Would a quick test be to swap to the stator pickup? 1 wire change and it might show a different behaviour.

Sent from my SM-G920F using Tapatalk

You mean plug in the red from the stator - bypassing the external pick up?

Yes, if you think your stator timing is reasonable it could be a quick test.


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[alanscottj]

Would a quick test be to swap to the stator pickup? 1 wire change and it might show a different behaviour.

Sent from my SM-G920F using Tapatalk

You mean plug in the red from the stator - bypassing the external pick up?

Yes, if you think your stator timing is reasonable it could be a quick test.


Sent from my SM-G920F using Tapatalk

Tried it - no difference whatsoever - still not picking up properly as I pull away

[alanscottj]

I've just had a bgm stator that showed correct ohms and my sip Speedo wouldn't work till 3000rpm swapped stator and worked straight away so tested the bgm again still showing ohms as it should be but something was breaking down

Sent from my SM-A320FL using Tapatalk

Looks like I'll have to try another stator

[Scooterdude]

When you charge your stator dont ditch the old one. Instead buy and fit a Ducati/Piaggio lt coil and pick up and keep as a spare.