Last summer I acquired a really nice '83 in the Pittsburgh area. The bike runs just fine but needed a jump to start because the battery is dead. When I bought the bike I was given a laundry list of the stuff the guy had done to it, but after working on these bikes for the last 10 years I know what he didn't do to it. So now that the weather has warmed up I'm going to get under the hood (so to speak). I've only ever worked on '82's (I've had three of them over the years), but an '83 is all Greek to me. My question is: Are any, if at all, any of the parts interchangable? i.e carbs, wiring, etc. I have plenty of '82 parts. I know some of the wiring harness has been chopped up, but I have 2 spares for my '82's. Also, what goes into working on these carbs? I have a spare set of '83's I got in a trade but they seem a bit more complicated.
He installed a fan switch, so I'm not sure that the wiring is copacetic.
Funny story: He asked $1,000USD for the bike, I offered $750. Two days later I get an email saying something to the effect of "No one wants this bike. Give me $500 and it's yours". Sold.
Quote from: munkyfistfight on March 30, 2015, 11:43:26 PM
Last summer I acquired a really nice '83 in the Pittsburgh area. The bike runs just fine but needed a jump to start because the battery is dead. When I bought the bike I was given a laundry list of the stuff the guy had done to it, but after working on these bikes for the last 10 years I know what he didn't do to it. So now that the weather has warmed up I'm going to get under the hood (so to speak). I've only ever worked on '82's (I've had three of them over the years), but an '83 is all Greek to me. My question is: Are any, if at all, any of the parts interchangable? i.e carbs, wiring, etc. I have plenty of '82 parts. I know some of the wiring harness has been chopped up, but I have 2 spares for my '82's. Also, what goes into working on these carbs? I have a spare set of '83's I got in a trade but they seem a bit more complicated.
He installed a fan switch, so I'm not sure that the wiring is copacetic.
Most of your 82 parts are best left for the 82's. 83 carbs will likely give less problems and should have an 83 gas tank wherever you use them..
If you want the 83 gas gauge to work you will need an 83 harness.
Most 82 parts will interchange with the 83 model.
Front brakes and struts, rear shock absorber, and carbs from the 83 are considered upgrades for the 82.
Fan switch is a minor concern and probably best left as is. BDC
'83 fuel tanks are different from the '82 model? In what way? This is the first time I've heard of this. --Steve
The petcock recirculates the fuel and they have a sensor for the fuel gauge. BDC
And, '82 tanks can't mount an '83 petcock or visa versa without a custom fabricated adapter.
So on the '83 fuel is returned to the fuel tank like on a fuel-injected bike?
I have a spare set of '83 carbs. The ones on the bike work but these ones are kind of gummy. I can't get the floats off (and at this point I'm too afraid to try). The plugs are all still there. Should I even mess with those? What's the procedure for working/syncing on those?
Also, a couple of the jets are stuck and the tips have been broken off. Does anyone have a good method for extracting them?
TS84, yes. An '82 tank can serve '83 carbs if the carb fuel return line blocked off. An '83 tank can serve '82 carbs if the fuel return spigot on the '83 petcock is blocked. Imho '82 and '83 carbs are equally difficult to work on.
Quote from: turbosteve84 on April 01, 2015, 09:32:11 AM
So on the '83 fuel is returned to the fuel tank like on a fuel-injected bike?
The '82 fuel pump uses a regulator and bypass arrangement to recirculate fuel back to it's inlet side when demand is satisfied via the float and inlet valves.
Admittedly I'm not an '83 owner but my understanding is when demand is satisfied on the '83, excess fuel transfers back to the petcock via the lower fuel line fitting in the picture.
QuoteAn '82 tank can serve '83 carbs if the carb fuel return line blocked off.
wouldn't it require a "T" installed in the '82's fuel delivery line instead to create a bypass route? Again, I'm not terribly familiar with the '83 circuit but thought I remember someone posting about it before. If I'm wrong someone will correct me.
The 83 fuel pump returns excess fuel to the petcock. The petcock releases this fuel at the top of the tank via a tube protruding from the top of the petcock. This top release maintains positive fuel pressure at the carbs irrespective of tank fuel level. If one attempts to use an 82 tank on 83 carbs by plugging the fuel return line, the carbs will receive whatever fuel pressure the pump produces without the effects of pressure regulation. I don't have direct knowledge of the results of operating in this configuration. In my opinion it is likely the higher pressure could overpower the carb floats and flood the engine.
To make the 83 carbs work as designed with an 82 tank, the top of tank fuel return must be implemented.
Otherwise, I recommend the return line be connected to the supply line. Since this defeats the fuel pump you could also bypass or remove it. This method renders fuel in the bottom portion of the tank unusable.
OK, how would this work -- '82 carbs using: '83 airbox, the front of an '83 carb (needed for the vacuum line to the '83 airbox), an '82 fuel tank and '82 petcock? In other words, the fuel pump is an '82 with the rest of the carbs being upgraded to '83.
Whew! This Vision thing is complicated! --Steve
For the 83 fuel pump to function as designed, excess fuel must be returned to the top of the tank as it is with the 83 petcock. If an 82 fuel pump is utilized, the fuel return line is unnecessary. This is irrespective of carb vintage.
Quote from: turbosteve84 on April 02, 2015, 10:10:39 AM
OK, how would this work -- '82 carbs using: '83 airbox, the front of an '83 carb (needed for the vacuum line to the '83 airbox), an '82 fuel tank and '82 petcock? In other words, the fuel pump is an '82 with the rest of the carbs being upgraded to '83.
Whew! This Vision thing is complicated! --Steve
Even more complicated, the front of the 82 carb was modified to provide a vacuum for the actuator. The 83 carb top doesn't fit the 82 carbs. BDC
I guess munkyfistfight's thread has been officially hijacked....
Steve, what are you trying to accomplish with the various parts? Do you not have a complete setup for either '82 or '83?
Glad you asked.
I have an '82. I bought an '83 front carb top and '83 air box. The fuel tank I'm having fabricated is being designed to accept an '82 petcock. Now I'm wondering if I need an '83 fuel pump and petcock to work with this setup. --Steve
You will find that '83 petcock and or parts are rather rare, and spendy if you can find them.
83 front carb top wont fit an 82 carb. BDC
Quote from: turbosteve84 on April 02, 2015, 08:32:32 PM
I have an '82. I bought an '83 front carb top and '83 air box. The fuel tank I'm having fabricated is being designed to accept an '82 petcock. Now I'm wondering if I need an '83 fuel pump and petcock to work with this setup. --Steve
You haven't said but I assume from your response the '82 carb and airbox are not flapper equipped. If that's the case I'd seek out the 82 carb top (or carbs) and flapper airbox for the '82 setup and petcock.
Yes, I have an '82 Vision, with '82 carbs. Converted the carbs to '83 style. Didn't know the fuel pump was different.
So, '83 front carb top and '83 airbox with flapper.
The fuel pump is an '82.
What problems, if any, would I have with this setup? --Steve
If it fits, then probably a late 82 carb top and flapper. That gives you a full late 82 setup rather than 83. No problems with that.
I'd recommend trying 120/120 pilot air jets rather than 135/135 (or 130/135). Consider also replacing your butterfly seals and backing off your accelerator pump by 5mm.
PoD, so the 120 recommendation would richen the pilot circuit? What does "backing off" the accel pump do?
Quote from: turbosteve84 on April 03, 2015, 09:16:01 AM
Yes, I have an '82 Vision, with '82 carbs. Converted the carbs to '83 style. Didn't know the fuel pump was different.
So, '83 front carb top and '83 airbox with flapper.
The fuel pump is an '82.
What problems, if any, would I have with this setup? --Steve
There are as many as 2 1/2 different types of '82 carb sets :) with the newer variants having the vacuum flapper capability. Most parts interchange on these. To my knowledge there is only one variant of '83 carbs and they have the vacuum flapper. There is no significant interchangeability between any '82 carb and the '83 carbs.
The bottom line is you'll want an airbox with the "vacuum" actuated flapper. To make that happen you'll also need a late model set of '82 carbs with those ports or a new style front carb top fitted to an old set plus the little filter thingy. Oh, and some slight jet changes too. Simple, eh!? Again, '82 and '83 carb parts don't interchange so if you have successfully fit a new style top to your front carb it is from a newer '82, not an '83.
The '82 pump will work fine with the '82 petcock/tank combo. I have no experience fitting the '83 airbox to an '82 frame but there may be interference on the rear cylinder's head-to-frame engine mounting bracket. If it clears, you have an '82 box, not an '83.
Amongst other things, the two years' carbs have different venturi sizes BTW but I'm unsure if the air horn side are similarly sized. If so, the rubbers to fit the airbox to carb air horn would potentially be an issue. To my knowledge, all carb outlet OD are the same so there is essentially one size of rubber intake manifold despite the venturi size difference.
Some pictures of your carbs from a few angles may clear up what you actually have.
Quote from: QBS on April 03, 2015, 04:41:54 PM
PoD, so the 120 recommendation would richen the pilot circuit? What does "backing off" the accel pump do?
Yes, it richens the pilot circuit, but that never turns off so you will get a slight enrichment at wider throttle as well. The 120/120 is standard jetting for Euro and Australasian models where emissions testing in the 80s was not so vigorous as USA.
On downdraught carbs (and the vision is no exception) a shot of fuel is squirted in to help with rapid acceleration - particularly when coming off idle. The goal is to deliver the right amount of fuel at the right time. You don't want to deliver too much fuel too soon (bogging), or too little fuel too late(poor throttle response). We don't have any control over the overall volume (that's done by the diaphragm size) or the volume/duration (controlled by the nozzle) but we can adjust the point at where it kicks in, which is done by the rod length. Backing it off 5mm was required in the Yamaha TSB for the flapper mod.
Don't just set it to 60mm but experiment a bit at a time. The optimum will change depending on configuration, weight, altitude etc. Mine is currently set and locktited at 58.5mm, but that will change with the new intake and exhaust
Quote from: Rikugun on April 03, 2015, 05:48:56 PM
The bottom line is you'll want an airbox with the "vacuum" actuated flapper.
Why? This has been interesting me lately. I know lots of people say the flapper is necessary but can't think of a good reason for it other than decreasing induction howl.
I had a cb900 (hornet) a while back that had the flapper on the throttle body side of airbox. The induction noise was the only reason it was there, just to meet emission regulations. It was removed with no noticeable effect on performance. In fact after I had removed all emission gear my bike would leave my mate's bike (also low km cb900 hornet that I had ridden and deemed equal performance to mine pre modding) behind even though I was 25kgs heavier and 6 inches taller sitting upright on a naked bike.
'83 front carb top fit just fine. Only difference I could see was the hose fitting on the front on the carb for the flapper box.
Replaced the butterfly valve seals.
I'll take your advice on the other two items.
--Steve
Quote from: ProphetOfDoom on April 03, 2015, 07:05:28 PM
Quote from: Rikugun on April 03, 2015, 05:48:56 PM
The bottom line is you'll want an airbox with the "vacuum" actuated flapper.
Why? This has been interesting me lately. I know lots of people say the flapper is necessary but can't think of a good reason for it other than decreasing induction howl.
I do appreciate you thinking outside the (air) box on this one. :) In answer to your question "why?" my answer is admittedly because that seems to be the conventional wisdom. I have no practical experience with the early style flappers or no flapper but I'm sure someone has tried it successfully. It seems many more have used the vacuum actuated setup with success so I thought that would be the most straightforward way to get Steve up and running.
Since we are theorizing about the flapper purpose I'll disagree with you since it wouldn't be much fun otherwise. :angel: From what I've read, the Visions ended up in the configuration they are because they ran poorly and stumbled badly as first delivered. Everyone has their theory for the stumble but I feel part of it is cured with the addition of the vacuum flapper. My personal feeling is the carb's unfortunate design makes for inherently clumsy and slow response - especially at low to moderate engine speeds. They react badly to momentary signal loss when the throttle is opened quickly and if not for a functioning and well adjusted accell pump the stumble is more pronounced.
My feeling is the flapper functions similarly to the diaphragm controlled slides on a CV type to buffer signal changes. Getting air in doesn't seem to be the issue. It's getting fuel to flow through the lengthy maze of passages that seems to be the trouble. The flapper modulates air until the fuel can catch up. That's my very un-scientific and completely un-tested theory anyway.
As an experiment I once ran my 83 with the air box flapper removed. This resulted in a tremendous off idle bog.
Quote from: turbosteve84 on April 04, 2015, 07:18:35 AM
'83 front carb top fit just fine. Only difference I could see was the hose fitting on the front on the carb for the flapper box.
The airbox connector port is on the carb top facing the camera. In addition, the "new style" carb top has that grey air filter hanging from the small hose. Note the carb bodies are of an earlier design prior to the second cross brace being added.
Rikugun -- ask and ye shall receive.
Here are some images of my "hybrid" setup. New '83 front carb top fit neatly with no MacGyvering. --Steve
Quote from: turbosteve84 on April 04, 2015, 05:50:18 PM
Rikugun -- ask and ye shall receive.
Here are some images of my "hybrid" setup. New '83 front carb top fit neatly with no MacGyvering. --Steve
Isn't that an 82 carb top?
Yes. '83 carbs have those holes along the top of the rim farther apart. So that is the updated flapper valve model for the '82.
Steve, Prophet and Fret are correct - what you have there is a set of run-of-the-mill '82 carbs. They may be an early body type as the second cross brace is not present like the photo I posted above. If someone sold you the carb top claiming it is an '83, they are mistaken and lucky for you as it wouldn't work if it was. :)
The picture below shows an '83 bowl gasket fit on an '82 carb body. The brass enrichener circuit tube and float arrangement are different amongst other features.
What's of particular interest is what looks like the cam chain tensioners sitting on the bench....
Why aren't they on the bike where they belong!? :'( :laugh:
When my '83 petcock crapped out, I was surprised to discover it was available from Yamaha. That was over a year ago, availability may have changed, but appparently it was used one or more other models. And yes it was spendy, but what a relief.
You're right. It is an '82 top.
I checked the part number of the box it came in (see attached images). Bought it OEM NOS. But it has the vacuum port on the front for use with the upgraded airbox so I'm using it. One of the images below shows the new carb top and the old. Another shows the airbox I'm using.
Cam chain adjusters: Yes, I tore the top end down to check everything and paint the cylinders. BTW, all 8 valve clearances were tight! Luckily I was able to use 3 of the shims to adjust some of the valves, and my local shop swapped shims for the others I needed. Those were the DAMN TIGHTEST VALVE SHIMS that I've ever encountered on any motorcycle I've ever worked on. No way I could have popped them without removing the cams! Even then I had a problem.
So, now you've seen my setup. I'm going to run (hopefully!) with it. Everything is super clean inside the carbs.
Fingers crossed. --Steve
I absolutely agree, use the updated carb top. My understanding is once they developed that upgrade, later units were delivered with the parts from the factory. Dealers may have upgraded units still on the floor and the kit was available to install yourself if one were so inclined. POD provided a PDF of the kit instructions on his resources page here: http://ridersofvision.net/rovforum/index.php?topic=12221.0 (http://ridersofvision.net/rovforum/index.php?topic=12221.0) It's the first item under Service Guides.
Of particular interest is the recommended accel rod adjustment on page 4 of the PDF. I think this adjustment was referenced by POD earlier in this thread.
I'm glad to hear how clean the carbs are as your chances for success improve greatly the cleaner they are. Clean carbs seems to go without saying but can't be stressed strongly enough with respect to these carbs in particular.
Shim removal can be difficult with the tool as it sometimes rides too far over the lip of the bucket interfering with removal. They may never have been checked which is why so many were out of adjustment.
Wow! Sorry for the delay in getting back. I'm glad this thread got so much attention. The carbs will always be a point of contention. I can tear my '82 carbs apart and put them back together in under 20 minutes. It wasn't until I actually had a giant fan to cool the radiator while I synced them that I actually was able to dial them in. These '83 carbs are still a complete mystery to me. Should I remove the plugs for the mixture screws? I also can't seem to get the float pins out so I don't really want to risk breaking a post (done that before). Any tips on removing stuck jet? Two of them have the heads broken off.
Quote from: Rikugun on April 06, 2015, 02:12:57 PM
Of particular interest is the recommended accel rod adjustment on page 4 of the PDF. I think this adjustment was referenced by POD earlier in this thread.
If you read any of the tuning guides for Holley or Weber carbs, they go on and on about the accelerator pump adjustment for fixing stumbles coming off idle.
Quote from: munkyfistfight on April 09, 2015, 04:25:16 PM
Should I remove the plugs for the mixture screws?
Yes indeed. How else do you adjust or replace them? If you live in California I believe that will get you thrown into gaol though.
Quote from: munkyfistfight on April 09, 2015, 04:25:16 PM
I also can't seem to get the float pins out so I don't really want to risk breaking a post (done that before).
The trick is to use a pin punch, not a standard nail punch as these get thick too quickly and you end up hammering on the top post. I made a pin punch by grinding a nail punch down so it's parallel for the first cm. Place the bottom post over a slightly open vice then tap tap. Gently at first till you get the feel of it. You need more force than you think, but with the pin punch and vice you aren't putting any force on the posts.
To replace the pin, use pliers between the bottom post and the pin end till it just pops in place.
The procedure is in Haynes
Quote from: munkyfistfight on April 09, 2015, 04:25:16 PM
Any tips on removing stuck jet? Two of them have the heads broken off.
I drilled and used a screw extractor. Worked well for me, though I know a lot of people hate ez-outs because they break and leave you even more in the crap. I don't know what a better alternative would be.
If I'm remembering correctly, V float posts are a tricky deal that, at least to me, is counter intuitive. It seems that the pin is slightly larger in diameter at the spread end than it is at its' other end. This means that if the punch force is applied to the smaller end of the pin without supporting the post that the bigger end is stuck into, that post will be broken off. This is because the force applied to the punch's' smaller end will be transferred without resistance to where the large end of the pin is stuck through the other post. The unsupported post then breaks off and the owner needs to apply the miracle of J-B Weld.
I was able to use a small screwdriver to twist in between the head of the pin and the post. That way the force is applied where it needs to be and not to the post. Just worked on the XS carbs and they have the same setup on the float pins.
Jeff, what a wonderful bit of advice. Thank you. I have always done things on the V as instructed by the Haynes, never looking for another way to go forward. I have perfect the flat blade screwdriver for this job.
Cool! Ok, next question...
Is the '83 sync rod supposed to be on the YICS side of the bike? I just took a look under my tank and it almost looks like the carbs were installed backwards compared to '82. The bike ran when I picked it up. It ran seemingly fine, although the battery was junk...This just looked confusing to me.