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hit rear brake and my bike idles faster ???
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@scooterihardleynewer avatar
scooterihardleynewer
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scooterihardleynewer
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noticed today on my 300 that when i hit the rear brake at a stop light the engine idles faster.
anyone else notice this?
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Rusty rope
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Rusty rope
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Wiki
It sounds like this is what you're experiencing: FAQ: Why does the engine sound different with the brakes on?
Quote:
While idling, the engine noise (and associated vibration) changes when the rear brake is applied because the rear wheel is being clamped to the engine via the brake calipers. This allows vibration to travel through the frame via different paths, and also provides additional dampening that otherwise doesn't occur very efficiently through the axle alone.

The change in engine noise and vibration is not because of additional load being put on the engine. Stopped is stopped, and the centrifugal clutch is disengaged regardless.
Hope it helps.

(It may also help reading through the wiki, Readme1st ! : Modern Vespa Wiki if you haven't already done so)

Edit: when you're stationary and the engine is running, you'll feel the difference through your butt and hear a slight change in tone if you switch between the front and rear brake.
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maxgt33
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Yep its vibration for sure. My BV does the same thing.
manoscoot
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manoscoot
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idle change
Mine does exactly that. Only the back brake. Never have found out why. Hope some one here has a good explanation.
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jimc
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The Hornet (GT200, aka Love Bug) and 'Dimples' - a GTS 300
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The explanation is above. When the suspension is locked via the rear brake, the resonant frequencies are changed - and the harmonics thereby. Nothing, nothing, has happened to the actual engine rpm.
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On my LX I can see the tach increase.
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scooterihardleynewer
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scooterihardleynewer
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thanks rusty
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jimc
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scootermarc69 wrote:
On my LX I can see the tach increase.
On my X9s with their own inbuilt (and quite accurate tach) no increase can be seen.

What tach have you fitted to your LX?
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Koso
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