Author Topic: another carb question - inlet restriction  (Read 2486 times)

Ian7

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another carb question - inlet restriction
« on: January 01, 2015, 10:19:09 PM »
While in the middle of doing the exhaust de-restriction, I noticed the carb breathes through a 1" square hole that immediately drops to about a 5/8 diameter tube....  does it make sense to carve out the tube and leave the bigger square opening, or does the carb need what looks like that purposeful pressure drop upstream? thx for all the help :-)

Ian7

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Re: another carb question - inlet restriction
« Reply #1 on: January 01, 2015, 10:28:43 PM »
this :

BettinANDlosing

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Re: another carb question - inlet restriction
« Reply #2 on: January 01, 2015, 10:53:41 PM »
You can just yank out the rubber tube, be ready to upjet.
2002 Kymco B&W 300; MRP 78MM "300CC", Naraku cam, Yoshimura rS3 exhaust, 17g Sliders, Yellow torque spring drilled airbox, stock carb #115 main #40 pj.

2001 "Yamaha" Zuma AKA MBK Booster; MHR OverRange, Dellorto 19mm BHBG, Polini "big" intake, RS-3 Rear shock, Stock cylinder.

zombie

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Re: another carb question - inlet restriction
« Reply #3 on: January 02, 2015, 12:37:14 AM »
It's a restriction to keep smaller jetting, and better fuel mileage. Nothing more than that.

It's the first part that is removed. (after the price tag)
"They have nothing in their whole imperial arsenal that can break the spirit of one Irishman who doesn't want to be broken."   Bobby Sands...

Ian7

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Re: another carb question - inlet restriction
« Reply #4 on: January 02, 2015, 01:48:07 PM »
thx  :-)

with bettinandlosings' exhaust de-restriction, and this inlet opening, would an 85 be big enough? (sea level in coastal georgia)
max performance at expense of piston life is NOT my goal  lol

BettinANDlosing

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Re: another carb question - inlet restriction
« Reply #5 on: January 02, 2015, 04:35:10 PM »
85 will most likely be too small but its a good starting point. Jetted right you shouldn't lose any longevity of the engine, only a few mpg's.
2002 Kymco B&W 300; MRP 78MM "300CC", Naraku cam, Yoshimura rS3 exhaust, 17g Sliders, Yellow torque spring drilled airbox, stock carb #115 main #40 pj.

2001 "Yamaha" Zuma AKA MBK Booster; MHR OverRange, Dellorto 19mm BHBG, Polini "big" intake, RS-3 Rear shock, Stock cylinder.

zombie

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Re: another carb question - inlet restriction
« Reply #6 on: January 02, 2015, 07:36:34 PM »
85=90 is ball park. +1 the engine will not suffer at all. They can do much more than this.
"They have nothing in their whole imperial arsenal that can break the spirit of one Irishman who doesn't want to be broken."   Bobby Sands...

BettinANDlosing

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Re: another carb question - inlet restriction
« Reply #7 on: January 02, 2015, 09:41:10 PM »
If anything taking away restrictions will ADD life to the engine, less restriction = better performance and longevity, if you don't floor it any more LOL.
2002 Kymco B&W 300; MRP 78MM "300CC", Naraku cam, Yoshimura rS3 exhaust, 17g Sliders, Yellow torque spring drilled airbox, stock carb #115 main #40 pj.

2001 "Yamaha" Zuma AKA MBK Booster; MHR OverRange, Dellorto 19mm BHBG, Polini "big" intake, RS-3 Rear shock, Stock cylinder.

BettinANDlosing

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Re: another carb question - inlet restriction
« Reply #8 on: January 28, 2015, 01:39:32 AM »
^^^^^^^^^ Look what I said, #85 will most likely be too small, then you yank it out and put in a #82 and think it'll run good? Dude, seriously follow advice given to you before raging when your scooter does not run right.
2002 Kymco B&W 300; MRP 78MM "300CC", Naraku cam, Yoshimura rS3 exhaust, 17g Sliders, Yellow torque spring drilled airbox, stock carb #115 main #40 pj.

2001 "Yamaha" Zuma AKA MBK Booster; MHR OverRange, Dellorto 19mm BHBG, Polini "big" intake, RS-3 Rear shock, Stock cylinder.

zombie

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Re: another carb question - inlet restriction
« Reply #9 on: January 28, 2015, 01:52:29 AM »
Did I miss something here?

A yanked post?
"They have nothing in their whole imperial arsenal that can break the spirit of one Irishman who doesn't want to be broken."   Bobby Sands...

BettinANDlosing

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Re: another carb question - inlet restriction
« Reply #10 on: January 28, 2015, 02:03:15 AM »
http://www.kymcoforum.com/index.php?topic=13410.msg133872#msg133872

This dude is seriously trying to blame me for screwing up his scooter.
2002 Kymco B&W 300; MRP 78MM "300CC", Naraku cam, Yoshimura rS3 exhaust, 17g Sliders, Yellow torque spring drilled airbox, stock carb #115 main #40 pj.

2001 "Yamaha" Zuma AKA MBK Booster; MHR OverRange, Dellorto 19mm BHBG, Polini "big" intake, RS-3 Rear shock, Stock cylinder.

zombie

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Re: another carb question - inlet restriction
« Reply #11 on: January 28, 2015, 02:20:18 AM »
I'll load up the dogs, you throw him the hamburger meat.

Meet you behind Sally's in 2 hours. 8)
"They have nothing in their whole imperial arsenal that can break the spirit of one Irishman who doesn't want to be broken."   Bobby Sands...

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