82 and 83 Carbs

[Blake]

I was just taking a look in the Haynes manual and noticed that the jetting for the 83 carbs were identical, unlike the 82's whose main jets are of different sizes.  Along with my other projects this winter, one of the things i want to do is put some K&N's on, (definately going to have to reject), and i was thinking that if the jets are the same for 83 carbs, if it would be easier? (use same size jets for both carbs).  Arent 83 Carbs slightly bigger (1 or 2mm?) than those on an 82?  so many questions so little space.. so to sum it up:

1. would 83 carbs work on an 82?
2. since the jets are the same on an 83, shouldnt they be the same on an 82?
3. since the jets are the same on an 83, im thinking it would make it easier to rejet, because your dealing with identical settings on two carbs, instead of 2 different settings.  would i be correct to think this?
and finally...
4.  If 83 carbs would indeed work (well) on an 82, would anyone happen to have a pair they would want to trade for a set of very nice chemdipped (yes, i will dip them, blow out all passages,  and have them nice and clean for you  ;D) 82 carbs, with the flapper vacuume top, AND the airbox (and a nice UNI filter thrown in too) ???  just wondering what your thoughts were.


Thanks,

Blake

[Lucky]

a couple of things
83 carbs will fit and work on an 82. ?the only "induction" differences are that the 83 (and probably all Vision intakes since) are radiused to improve flow. ?
you might be surprised to find that there are actually 3 versions of Vision carbs. ?early 82's have no stop adjustment screw on the accel pump, and the pilot jets and emultion tubes are seperate in the carb bodys. ?on late 82's the pilots have the emultion tubes soldered directly on to them. ?venturi size is the same.

83 carbs are an entirely different animal. internal passages are different, as are gasketts, even the accl pump nozles are longer. ?also the pilot mix screws are moved by an adjuster whereas on an 82 you turn the screw directly. ?look here for pics: http://www.geocities.com/lucky_142/83mix.html

throttle cable and choke cable attachment points are the same, It is a straight swap. ?the jetting will be different of course, but i don't think other than minor adjustments you would have any problems.

you will need an 83 petcock to go with the carb because the fuel regulator (which is seperate from the pump on an 83) has a return for excess fuel to return to the tank.
 ?--Lucky

i've been looking for a set of 83 carbs solely for the fuel milage. (they seem to be better) but have given up because i have gotten to the point with mine that i'm happy with the bikes performance.

1. would 83 carbs work on an 82?
yes
2. since the jets are the same on an 83, shouldnt they be the same on an 82?
no
3. since the jets are the same on an 83, im thinking it would make it easier to rejet, because your dealing with identical settings on two carbs, instead of 2 different settings. ?would i be correct to think this?
good question
and finally...
4. ?If 83 carbs would indeed work (well) on an 82, would anyone happen to have a pair they would want to trade for a set of very nice chemdipped (yes, i will dip them, blow out all passages, ?and have them nice and clean for you ?;D) 82 carbs, with the flapper vacuume top, AND the airbox (and a nice UNI filter thrown in too) ??? ?just wondering what your thoughts were.


Thanks,

Blake
[/quote]

[Lucky]

in my previous post i wrote:

you will need an 83 petcock to go with the carb because the fuel regulator (which is seperate from the pump on an 83) has a return for excess fuel to return to the tank.

aprently this message board doesn't like bad words, because it changed  "petc*ck"  to "petthingy"

I can't stop laughing...

[Kenny]

 
 :) Hi Blake,
 ? ? ?I installed 83 carbs on my 82 (the Hannigan one). It worked out well I had an 83 fuel tank so I did not use a pettythingy. I had to modify the upper engine mount - removed a small amount of material as the carb body came into contact. The bike ran 100% better, although I couldn't outrun my wifes 83 unless we were in the twistys.
 ? ?I had a great summer of riding and was out to the west coast and back twice on a R1150rt - what a great long distance machine, We also put about 5000 ks on the Vision and after ?the 1150 I am installing stainless brake lines.
 ? ? I hope everyone else had a great season.
 ? ? ? ? ? ? ?Cheers ?Ken S
 ?ps: I like the new forum. ?

[Dave T.]

Wow, I don't believe how much fluff is on this message board compared to the last one, oh well  ;).

I went through all this before with lucky and I am also concerned with fuel mileage. I went up two sizes on my main jets (82 carbs, 2nd edition). One time I got close to 200 miles on a tank, but since it's been around 150 miles. Not very good. I may try going to 127.5 on both the front and rear carbs next spring. I still don't know why they have different jet sizes on each 82 carb.

I gotta try this censor thing. Petcock. Pussy.  ;D

I am going to pull apart the motor this winter and spring and either just put new rings to boost compression. Also I am going to check the peening of the starter clutch bolts and put the "right" seal in the starter. My valve cover gaskets leak, I have a complete gasket set from Dennis Kirk to put in. Any other suggestions in the motor?  :-/

[Blake]

Hey DT..not sure of what else right off the top of my head, but one thing i would suggest checking (which i also will be doing this winter) is to check your valve clearance, and also lap your valves to make sure there's a good seal.   with today being such a nice day, and tomorrow supposed to be just as good, im going to drop my engine so i can start cleaning it up and fixing what needs to be fixed in time for spring.


Good luck

Blake

[jasonm.]

After reading all the responses. I don't think anyone hit on the reason the jetting is the same on the '83 carbs front and rear. Hear it is...The '83 uses different front header pipes than the '82. This allowed the jetting to be the same. This had something to do with reducing the i.d. of the pipes. Thus increasing the velocity(flow) of the exhaust. If you get '83 front pipes your '82 will run just like an '83 after the carb swap. ;)

[Dave T.]

Interesting. I seem to notice on my 82  :o that the rear header 2 into 1 seems much more restrictive than the front header pipe (diameter wise). So since we have more velocity in the rear, we can move more air through the cylinder?  ???
I would think there would be more backpressure than the front cylinder thus running a leaner jet in the rear cylinder? Hmm. I would have to be a Yamaha engineer with the I.D. specs throughout the exhaust to figger out that one. I don't have the OEM pipes anyway, I have the cool MAC pipes. 8)

I gotta try that censor thing again, bear with me if they print out the uncenored words...

F**K = fuck

s**t = shit                  :-X

[swellman]

I know this will be hard to believe, but carbs that are jetted differently like the ones on the 82, are actually more refined.  Someone took the time to jet each cylinder individually.  What's funny about this is that the Vision is well known for it's short development time.  That's why they had to have a mid-year recall for the airbox, and why the 83 is so different.  Maybe they changed the exhaust ports on the 83 just so the carbs could be identical.

And I guess we'll have to say 'fuel valve' from now on.