Bogging Down , Won't Pull Away.

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immylam
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Just rebuilt Rapido 225 , had casings fixed at oiltech. Just studs though. Revs ok although stuttery on full revs and ticks over etc but on trying to pull away just bogs down. Last night tried a new carb , stator , CDI . lead , plug , supp cap. What else can anyone suggest. Changed oil seal to one of those brown ones (and a few have failed) would this cause these symptoms as it isn't overly smokey and not too difficult to start. Might be the real amateur mistake of piston in wrong way? (although I don't think so) Would it cause this type of running?
Adam_Winstone
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Have you tried it with the loom's green out of the CDI, which would bypass the ignition switch and loom (ignition would remain live)? I say this as a failing ignition switch can do this.

Did you change the carb as a whole or just swap internals to a new body? I ask as a punctured float can do similar.

Best of luck.

Adam
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immylam
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I changed the whole carb from an OKI to a dellorto (brand new) and jetted accordingly. I did try bypassing the ignition so I can rule that out. Thanks.
holty
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sounds like you have tried the most obvious things, is it just too rich, maybe choke not closing fully, or idle jet too large, is the needle on the middle groove, is it better if you use the top groove, a couple of things to check or try ?
good luck,
holty
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coaster
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Have you got a filter on? if so, try it without as it might be the old problem of fuel gathering in the elbow...worth a try 8-)
mr mugello
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Split in carb rubber mount if fitted.
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immylam
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Running without filter and just checked carb rubber , no split but good shout though , I hadn't checked that. Ah well no Scarborough for me ....teach me not to have both scooters off the road at the same time and rebuild for mot a few days before rally.
mr mugello
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I take it you have tried simply tinkering with needle heights on BOTH carbs.
Meds
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Have you checked your timing.
The timing marks on my flywheel/stator combination have a 3 degrees Difference between static and strobed.
Good luck, hope you make it to Scarborough.
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Bofs
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Have you done a leak-down test on the engine. I had a very similar experience recently due to a badly cast inlet manifold that was like a teabag, couldn`t get it to pull away right,just bogged down, but ran ok when the revs were up. Did the bicycle tube and foot-pump test and lo and behold air was escaping through the stud holes in the manifold. JB Welded it and it ran perfectly after that. Worth a check.
Muffspeed....no muff too tuff
Bad Samaritans SC

1957 Zundapp Betta 500 Auto
1966 Motovespa Sprint 210 Polossi
1960 Lambretta Cutdown 205 Project
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