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Crazy BGM jet kit for bellmouth/venturi setups
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Ray8
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Ray8
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Can't wrap my head around this kit

"Big air big fuel" has been around for a while, but it still doesn't make sense to me. The description also seems to contradict itself.

Wild guess:
With a venturi/big airbox cover setup, negative pressure above the (open to the accelerated airstream) AC's increases air correction (-) to allow these crazy jets.

https://www.scooter-center.com/abstimmset-fuer-vergaser-mit-venturi-bgm-pro-162-200-hauptduesenset-nebenduese-mischrohr-hauptluftkorrekturduese/p-45952.html
buongiorno
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buongiorno
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Saying "Big air big fuel" automatically makes me think Forced Induction Laughing emoticon
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SaFiS
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SaFiS
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Germans and their big numbers ROFL emoticon ROFL emoticon
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Ray8
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SaFiS wrote:
Germans and their big numbers ROFL emoticon ROFL emoticon
Also the Germans with their afr's, dyno's, egt's, Alps rides, etc.
It has to work, right?

The big fuel big air concept is also the Ranger's jetting on the Malossi (with typical jetting) vs Ranger comparison by SCK:


https://www.scooter-center.com/en/cylinder-comparison-vespa-px200-malossi-sport-210-vmc-ranger-213-quattrini-m244/20251202/b-3816.html
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MCsteve
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MCsteve
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Ray8 wrote:
Also the Germans with their afr's, dyno's, egt's, Alps rides, etc.
It has to work, right?

The big fuel big air concept is also the Ranger's jetting on the Malossi (with typical jetting) vs Ranger comparison by SCK:


https://www.scooter-center.com/en/cylinder-comparison-vespa-px200-malossi-sport-210-vmc-ranger-213-quattrini-m244/20251202/b-3816.html
https://www.sip-scootershop.com/en/blog/venturi-comparison_p6674

The recent sip Venturi/airbox test kinda puts this Malossi vs Vmc test in a different light.

The Malossi was tested as a stock filter/large airbox, and the Vmc with Venturi/large airbox, with ~2hp difference. That's similar to the difference in the sip test just changing the filter and airbox.

I think the difference between kits in an apples to apples comparison is probably pretty negligible.
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MCsteve wrote:
https://www.sip-scootershop.com/en/blog/venturi-comparison_p6674

The recent sip Venturi/airbox test kinda puts this Malossi vs Vmc test in a different light.

The Malossi was tested as a stock filter/large airbox, and the Vmc with Venturi/large airbox, with ~2hp difference. That's similar to the difference in the sip test just changing the filter and airbox.

I think the difference between kits in an apples to apples comparison is probably pretty negligible.
Agreed.

Interesting that some are riding with a big airbox cover and stock filter.
I "think" I get the idea.
More vortex with more space above the bowl cover.
Also more pulse buffering.
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