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Vespa Rally 180
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Vespa Rally 180
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Hi guys

I have a Rally with a P200e engine with ported casings from SIP and a 210 Malossi kit and a Sito-plus exhaust. However, the bike does little over 60mph maybe 65 at a push. It does have quick excelleration, but I'm disapointed with the top end. At the moment I have a standard 24mm carb with a 130 main jet. The engine has the the T5 forth gear and up-rated clutch. Other guys swear they get in access of 70mph which is what I'm looking for as I use it for work and use quite busy roads, any ideas why mine is slow top end?
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⚠️ Last edited by rich2111 on UTC; edited 2 times
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Petty Tyrant
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Petty Tyrant
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Moved to NSM.
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'74 Rally, '66 SS180, '64 GSmk2, & a mess of smallies.
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'74 Rally, '66 SS180, '64 GSmk2, & a mess of smallies.
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How are you gauging your speed? Don't trust the speedo. A proper GPS seems to be the way to go.

I think your estimation is correct tho, you should be getting more top end out of that. I've been clocked at 68 on a Rally 200, bone stock except a Sito plus.

By a cop no less. But I don't recommend that method.

Other thoughts that come to mind are double checking the timing, running a hotter plug, and making sure your main jet is super clean.
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Ossessionato
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Ossessionato
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Is the kit broken in yet and was it broken in correctly? That shitto exhaust is rubbish and it not good with the kit you have. Get a real expansion chamber and you will get that top end you are looking for.
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Hooked
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Hooked
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Do you know what your timing is? Have you checked it with a strobe gun? Somewhere around 17-18 degrees btdc should be right.
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VLBJS1 wrote:
Is the kit broken in yet and was it broken in correctly? That shitto exhaust is rubbish and it not good with the kit you have. Get a real expansion chamber and you will get that top end you are looking for.
Agreed. A proper expansion pipe will let it rev much higher and be more efficient at the same time. Without the high RPM power the T5 4th gear is working against you as it gives you a lower final gear ratio.
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1970 Vespa Rally 180
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1970 Vespa Rally 180
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oopsclunkthud wrote:
VLBJS1 wrote:
Is the kit broken in yet and was it broken in correctly? That shitto exhaust is rubbish and it not good with the kit you have. Get a real expansion chamber and you will get that top end you are looking for.
Agreed. A proper expansion pipe will let it rev much higher and be more efficient at the same time. Without the high RPM power the T5 4th gear is working against you as it gives you a lower final gear ratio.
i want to understand this. badly. but i think its gonna be math related.
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Ossessionato
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Ossessionato
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oopsclunkthud wrote:
VLBJS1 wrote:
Is the kit broken in yet and was it broken in correctly? That shitto exhaust is rubbish and it not good with the kit you have. Get a real expansion chamber and you will get that top end you are looking for.
Agreed. A proper expansion pipe will let it rev much higher and be more efficient at the same time. Without the high RPM power the T5 4th gear is working against you as it gives you a lower final gear ratio.
+1 Patrick has a much better approach than I do. Well said mate.
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Vespa Rally 180
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Location: Cambridge UK
 
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Vespa Rally 180
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Tining should be right as had it set up in a scooter shop, but cant harm getting someone to check it. Also mught move to a 26mm carb as been told they run better than the 24mm. And looks like its another new exhaust, probably a RZ RH as still want to keep the spare wheel under the panel. Also getting a lightened flywheel as the one I have has the starter motor design so quite heavy.
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