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double h
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Posts: 153
Joined: Sat Nov 15, 2014 12:29 am
Main scooter: SIL GP 200
Location: Dumfries SW Scotland
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johnny650 wrote:ok .................sorry my suggestions were of no interest to you . Good luck anyway
They are, was at 22 now at 19. Cheapo electronic ignition kit ,if all else fails I'll fork out for a quality kit.
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double h
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Joined: Sat Nov 15, 2014 12:29 am
Main scooter: SIL GP 200
Location: Dumfries SW Scotland
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This may not be helping.Image
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garry inglis
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Main scooter: ts1 230 and rb200
Location: darlington
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failing head gasket is that plug all the way in
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double h
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Main scooter: SIL GP 200
Location: Dumfries SW Scotland
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garry inglis wrote:failing head gasket is that plug all the way in
Aye the plugs all the way in, it's in the machine shop now to get sorted.
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double h
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Main scooter: SIL GP 200
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Fun in the sun. Air leak found.Image
hendy
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Main scooter: lambretta li 125
Location: Tyne and Wear
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Where?
Adam_Winstone
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No, as Holty immediately stated, this will not be the issue with not pulling 4th gear.

If yours has the original li150 4th gear ratio of 5.2:1 then that represents the same 4th gear ratio that the GP200 runs. Q: Is your GP150 top end putting out the same power spread as the GP200..... A: No. As such, your gearing is too long and I'm expecting to hear that it is great in gears 1-3 but then struggles to pull 4th (?).

Adam
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double h
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Main scooter: SIL GP 200
Location: Dumfries SW Scotland
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hendy wrote:Where?
Sorted when I took the pic. Was one of the nuts ,New gasket with silicon.
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double h
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Main scooter: SIL GP 200
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Adam_Winstone wrote:No, as Holty immediately stated, this will not be the issue with not pulling 4th gear.

If yours has the original li150 4th gear ratio of 5.2:1 then that represents the same 4th gear ratio that the GP200 runs. Q: Is your GP150 top end putting out the same power spread as the GP200..... A: No. As such, your gearing is too long and I'm expecting to hear that it is great in gears 1-3 but then struggles to pull 4th (?).

Adam
Aye you are correct. There's a big jump from 3 to 4 but my thoughts were if a Spanish s2 top end could pull it surely a Gp should.?
Adam_Winstone
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^... don't worry, that is a VERY common mistake to make. As power from standard motors went up, so did the rev range that they operate at, with the dear ratios being lowered (higher number) to suit:

LI125 = 5.7, GP125 = 6.1

LI150 = 5.2, GP150 = 5.7

TV200 = 4.4, SX200 = 4.8, GP200 = 5.2

... which clearly shows the changes to gear ratios over time. Also note that any other changes that you've made to the engine spec, by way of bigger carb or free flowing pipe (e.g. later SIII or clubman) will have further compounded the issue by pushing power higher up the rev range, making it even less likely to pull 4th.

Good luck getting this sorted.

Adam
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