81 gl1100 single carb using the motorcraft/weber 740?

[joedrum]

well looks rather good to me also... a good move from here would be to go 200 air bleed that will lean it ...and the easiest jet to deal with

 

[81 Gwing]

i got it a home depot, 3ft was $11.73. i cut the hose at 5in each. the two cyl that are a straight shot in are at 4-1/8 the other two are at 4-1/4 for the s bend.i have grab rail pressed into the VW plenum. so i put one end of the pvc in some boiling water to soften it and pushed it over the grab rail. i dont have any vac leaks,BUT i still wanna make a sleeve to go over the joint of the pvc and plenum..

ok, i soldiered the 130 hole in my pri main jet and drilled it out ta a 120. i havent payed to much attention to the sec side as far as jetting goes until l today. its runnin lean.so...i drilled the sec main jet to 1.016mm. WAHT a difference for the better. it hasent pulled that hard since ive done the swap :salute:

plug check with the 120 main

 

[81 Gwing]

joedrum » Sat Aug 09, 2014 6:22 pm[/url]":dnyih6bm]
well looks rather good to me also... a good move from here would be to go 200 air bleed that will lean it ...and the easiest jet to deal with

i tried the 200,it doesnt like it

 

[Ansimp]

Looks good to me :good:
One thing I will say is that I prefer to do fuel economy checks using as much fuel as possible that way your filling technique is averaged over a greater volume. For the Rats Nest it seems to be around the 130 miles before I have to select reserve so that is my normal refilling point.

 

[81 Gwing]

when i had the stock carbs, 202mi i would have to put in on reserve. i was gettin 48.7 mpg

as far as the plugs go,this is my opinion, any black sutty stuff shouldnt be there. they should be clean

 

[81 Gwing]

Ansimp » Sat Aug 09, 2014 8:03 pm[/url]":30w4bdwg]
Looks good to me :good:
One thing I will say is that I prefer to do fuel economy checks using as much fuel as possible that way your filling technique is averaged over a greater volume. For the Rats Nest it seems to be around the 130 miles before I have to select reserve so that is my normal refilling point.

how many gallons it take at 130?

 

[Ansimp]

4.1 US gal

Rats Nest fuel usage 16.41 qt 4.1 US gal

• Ansimp
• Aug 9, 2014

130 miles on 4.1 US gal 31.7 mpg

• Ansimp
• Aug 9, 2014

I use the iPhone to take photos at the pump so that it is easy to convert later, notice how much 4.1 gal cost in AUD ( that is our 95 octane no ethanol fuel)

 

[81 Gwing]

your spark plugs must not look to good

 

[Ansimp]

81 Gwing » Sun Aug 10, 2014 10:47 am[/url]":3jaw2cfc]
your spark plugs must not look to good

I think it is more of a throttle position issue
viewtopic.php?f=23&t=8485&hilit=Rats+nest#p126797

 

[81 Gwing]

i did some sec. jetting. sec main jet size in now a 120,200 air bleed,T02 well tube and 60 idle jet. the 120 main jet made a huge difference :yahoo: . so after a bunch of WOT runs and 151mi later(still had a 1/4 tank) i filled her up. 3.4gal.===== 44.4 :Egyptian:

 

[dan filipi]

Very impressive mpg even without wot runs.
I'm pretty sure your the first to post such incredible results.

 

[joedrum]

yes your mpg will change down some now but .. its using it ... hooch idle is 80 main is 140 and air is 160 so i am way richer ..but secondary is 2mm bigger barrel 3mm bigger fixed choke and flows much m ore air

 

[Ansimp]

81 Gwing » Mon Aug 11, 2014 4:55 am[/url]":1fhzbj9q]
i did some sec. jetting. sec main jet size in now a 120,200 air bleed,T02 well tube and 60 idle jet. the 120 main jet made a huge difference :yahoo: . so after a bunch of WOT runs and 151mi later(still had a 1/4 tank) i filled her up. 3.4gal.===== 44.4 :Egyptian:

Excellent results :clapping: :salute: :good:

 

[81 Gwing]

been awhile....got my stock carbs cleaned,been runnin um for a year or so now. best MPG 49.8 with me and mumma on it. so i picked up a naked 81 with no carbs,so i put the single carb setup on that. when i first did the single carb there was alot of talk about heating the intake,well im gonna. its not done yet but heres what i have so far.just need ta weld on some fittins for the water lines

 

[slabghost]

Nice welds.

 

[81 Gwing]

slabghost » Wed Sep 06, 2017 6:56 pm[/url]":3dh1pyio]
Nice welds.

thanks

 

[D-50Dave]

Beautiful work!

 

[joedrum]

As always your work is very good ....

 

[81 Gwing]

have any of you guys seen anyone that has done what i did to that intake??

 

[slabghost]

Actually yes. And several others have attached coolant manifolds or heaters in various ways. Most have found that once the carb is adjusted right heat is unneeded.