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when u have jets larger in the 2 and 3 cyclinder and smaller ione in the 1 and 4? is it called jet laddering? im tring to find info on why and pros and cons on it...
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_____________________________________________ 1979 XS 1100 Special "The judge" mods- K&N air pods, 4-1 mac, 147.5 pilots, 57.5 mains, LED turn signal, cafe bars, HEL translucent yellow stainless steel brake line, dyna coil (dc2-1), raptor 660 mc, r6 controls..(sold)
1982 gs1100e "all business" cafe project
1980 gs1000g "stock"
1982 honda express "stretched 10 inch(my daughters scooter)
2008 jmstar 150cc Chinese scooter ( wife's bike) -
No pros or cons really............air cooled and inner two cyl. run a bit hotter causing them to run a bit leaner so couple steps richer feeding those two cyls. compensate some for that........ some set thier carbs up like that........ some don't.81H Venturer1100 "The Bentley" (on steroids) 97 Yamaha YZ250(age reducer) 92 Honda ST1100 "Twisty"(touring rocket) Age is relative to the number of seconds counted 'airing' out an 85ft. table-top. -
That was done on the later '80-up bikes because the factory jetting was pretty lean for emissions purposes and the motors ran a bit hotter. As motoman said, they increased the jets on the two inner cylinders to compensate for this. There's no real performance advantage...Fast, Cheap, Reliable... Pick any two
'78E original owner - resto project
'78E ???? owner - Modder project FJ forks, 4-piston calipers F/R, 160/80-16 rear tire
'82 XJ rebuild project
'80SG restified, red SOLD
'79F parts...
'81H more parts...
Other current bikes:
'93 XL1200 Anniversary Sportster 85RWHP
'86 XL883/1200 Chopper
'82 XL1000 w/1450cc Buell, Baker 6-speed, in-progress project
Cage: '13 Mustang GT/CS with a few 'custom' touches
Yep, can't leave nuthin' alone...Comment
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Having owned two 81 models now, and opened up more than a few carbs, I have yet to find any still jetted like that. And I have never done so myself. All the carbs I have worked on worked excellent on every bike to date.
Like stated, it was a way to give added cooling to the inner cylinders due to the richer mix. None of my engines have ever shown a lean condition in the inner cylinders. HTHLife is what happens while your planning everything else!
When your work speaks for itself, don't interrupt.
81 XS1100 Special - Humpty Dumpty
80 XS1100 Special - Project Resurrection
Previously owned
93 GSX600F
80 XS1100 Special - Ruby
81 XS1100 Special
81 CB750 C
80 CB750 C
78 XS750Comment
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IIRC, Yamaha stopped doing this after a few years. They probably had good reason to.2H7 (79) owned since '89
3H3 owned since '06
"If it ain't broke, modify it"
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It actually started with the 79 specials. While the 137.5 jets were on all carbs, 2 & 3 had emulsion tubes with less side holes to effectively reduce the air mixture / increase the fuel to air ratio for inner cyl cooling. Later specials did this with larger jets in 2&3.
The idea behind this was that the standards would see more cruising miles and the specials would see more boulevard miles. Basically proved to be pretty irrelevant .79SF
XJ11
78EComment
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