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74 sprint compression test
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@kylesalter avatar
kyle.salter
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kyle.salter
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@kylesalter avatar
vespas, lambrettas, cushman, and mopeds
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i have between 95 and 100 psi compression. that about right?
stock everything on a 74 sprint
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Rover Eric
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1965 Vespa SS180, 1963 Lambretta LI150
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Rover Eric
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@rover_eric avatar
1965 Vespa SS180, 1963 Lambretta LI150
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Location: Detroit, Michigan
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Is it RIGHT? Eh ...it will run

A brand new, properly gapped top end will net you around 120. Your bike will altogether NOT run at like 80-85psi.

You're on the lower end of the spectrum, but the bike will work fine and start up readily. You just won't have all the power it's capable of.

*edit* did you measure that hot or cold ?
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@kylesalter avatar
kyle.salter
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kyle.salter
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wow it runs like a top and again other sprint it kills them. top speed is 60 to 62 mph.
VLBJS1
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VLBJS1
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kyle.salter wrote:
wow it runs like a top and again other sprint it kills them. top speed is 60 to 62 mph.
Are you sure it's not KPH? Razz emoticon
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@kylesalter avatar
kyle.salter
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kyle.salter
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@kylesalter avatar
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nope psi
jimmyb865
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nothing at all
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Location: westla
 
jimmyb865
nothing at all
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UTC quote
try another comp. tester

that performance is impossible from a low end compression

you have to remember the high pressure is what helps the ignition

it is the POWER in the POWER band.

i may be wrong but doubt it
@koenig_blues avatar
koenig blues
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a not so normal vbb2 '64, a weirdo vbx '86, a not so normal pts100 '82 and a yellow sunshine '74 sprint
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koenig blues
Veni, Vidi, Posti
@koenig_blues avatar
a not so normal vbb2 '64, a weirdo vbx '86, a not so normal pts100 '82 and a yellow sunshine '74 sprint
Joined: UTC
Posts: 5804
Location: Indo
UTC quote
jimmyb865 wrote:
try another comp. tester

that performance is impossible from a low end compression

you have to remember the high pressure is what helps the ignition

it is the POWER in the POWER band.

i may be wrong but doubt it
+1 cant agree more, higher comp higher performance while low end comp low performance Razz emoticon
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