delete this

fredintoon said:
Hi ron,
your buddy Jacob sounds like one of the good guys but I don't recommend that you ask him to rebuild your carbs
because a professional carb strip & rebuild will cost way North of buying a good used carb set.
As others have posted, your carb set could well be FUBAR and you are stuck with buying a good used set anyway.
Note that the list has several posts from guys who have swapped their stock carbs for aftermarket units so there
could be some take-offs available. Try a want ad in the list's classifieds.
In the hope that your set is salvageable I'd ask buddy Jacob if he has an ultrasonic cleaning bath and if he'd
let you put your carb-set in it overnight for a small fee or a return favor.
Click to expand...


http://www.ebay.com/itm/272692899122?ul_noapp=true


i sure hope these are the right ones
 
Yes, the carbs should have been re-jetted for the mods you have, but who knows what you'll find. The P.O. could have tried but not gotten it right, or maybe he changed nothing. I really believe there are more Einsteins in the world than there are people who know how to properly re-jet carbs, lol. Here's a listing of the stock sizes and settings .....

7wbHkpb.jpg
 
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I'd pass on those. They appear to be '77 and older carbs. Some of the sets may not even be from a 650 either.
 
5twins said:
Yes, the carbs should have been re-jetted for the mods you have, but who knows what you'll find. The P.O. could have tried but not gotten it right, or maybe he changed nothing. I really believe there are more Einsteins in the world than there are people who know how to properly re-jet carbs, lol. Here's a listing of the stock sizes and settings .....

CarbSpecsReducedSize.jpg
Click to expand...
awesome.bookmarked now.
 
ron bayless said:
too late.I already had to buy them since I was high bidder.I may have just wasted 100 dollars.I dont understand why 77 would not work on a 78.
Click to expand...
Hi Ron,
well, I don't understand that neither, let us know how they work, eh?
However, even if the 77/78 incompatibility thing is true, you are not out $100 because you can always sell the 77s on to someone with a 77 who really needs them. You may well lose some of the money to shipping costs and you'll certainly lose some time finding carbs that will work on your bike.
 
2. Q. I am changing to aftermarket exhaust and/or air filters what jets do I need ?
A. Every bike varies and a lot of factors effect this so a plug read & testing is the only real way to answer this (Altitude, ignition, engine compression & other factors effect tune). Spark plugs should show a light tan color on the insulator. Our Vague best guess is - 1980-84 models with stock 34mm CV carbs (North America) usually seem to require (about) a Main jet 142.5 - 147.5, Pilot Jet of #45, Air Jet of # 127.5 , Idle mixture screws set at 2.5- 3 turns out, carbs in sync, fuel level shut-off in float bowl set high. Check that fuel flow from petcock is good, No backup of sediment at float valve screen (stock). These carbs have a definite limit on fuel delivery and it seems that the more open the exhaust is the harder it gets to tune these carbs. Needle Jets need to be clean and there should be no air leaks or obstructions to flow of good clean, new fuel.


1970-79 Carbs usually need (about) a #140-145 main jet, up a size on the pilot jet,Carbs in Sync & pilot mixture screws adjusted. The 70-79 Stock CV carbs are very superior to the later types. Set idle to 1200 RPM. Make sure petcocks flow & that there is no air leaks.

I found this interesting.Not to use the dreaded car jargon since it makes some people cringe but a small block chevy is a small block chevy.Matters little what year.I cant imagine on all constant velocity 38s there being a problem with interchanging. Especially only one year different.The jetting article i found is very old, but it gives me some idea what to do with my 2 into 1 exhausts.plus i can take the jets out of the present carbs to see if they match up with this article.
 
It isn't that they won't work. If one of the three pair is a good set well you are golden. If it happens to be the 74-75 set then you get to shop for a dual cable throttle.
Did you even give thought to soaking your originals in diesel, kerosene or tranmission fluid? Something that might help them slick up?
 
i have used dawn,evaporust,mek for several hours,and apple cider vinegar.Ican try trans fluid i guess.However, after spending now a 100 bucks on fluids I wish I had spent that on a different set of carburetors.Some things are just too corroded to bring back.If you saw the very first pictures of the floats i posted you might concur.
 
Yes, it's not that the '76-'77 set won't work, it's just different from your current '78-'79 set. Jetting will be completely different as will the re-jetting specs required. That old mumbo jumbo you quoted really doesn't apply much. The main jet recommendations are too rich for most of the BS38 carb sets. You might get into the low 140s on a '78-'79 set but probably not on any of the earlier sets. It's not so much the number of the size but rather the number of sizes you go up, and that's usually 2 to 4.

I hope your eBay purchase works out. The seller's description is rather vague. Are you getting 3 sets of carbs or just one out of 3 he has for sale? I hope it's the 3 sets because like I said, they're not all 650 carbs. The set in the 1st 2 pics is. That's the '76-'77 set. The set in the 3rd pic is not a 650 carb set. Similar BS38 Mikunis yes, but not off a 650. The set in the 4th pic I'm not sure about. They could be a '74-'75 set as WER said, but the float bowls with no nipple on them came from a '78-'79 set. That means they take a different type of pilot jet than the '74-'75 set was designed to use. That may work OK but might not.
 
obviously you are an expert on the 650 carbs.I am not.that old mumbo jumbo as you put it was from an article written way back, about 75 or 76 I think. I thought it was good information.That is because I dont know anything about these carbs.The ebay seller did say it was 3 sets of carbs. One was rebuilt.I dont know what rebuilt means to him.If the others arent for a xs then identifying them will not be something i can do. Perhaps someone might be interested in buying them if i knew what they were. Someone suggested finding some 78 or 79 carbs and rebuild them.That is what I have tried to do in vain every day for several days.I was trying to find a set with working chokes slides and moving butterflies to accomplish that. According to you, I have bought the wrong parts. I trusted the seller. There are many things pertinent to a motorcycle I am aware of what is and isnt what is claimed.Unfortunately the xs carb is not one of them. I appreciate your input.
 
TwoManyXS1Bs said:
Ron, since you've tallied over 100 posts, you're enabled to access the "Laboratory" forum. Members 650skull and gggGary took on the enormous challenge of trying to put together a comprehensive "Carb ID" thread. Unfinished, work in progress, but chock full of handy info. See if this information overload helps wrap your head around this stuff:

http://www.xs650.com/threads/carb-id.42896/

http://www.xs650.com/threads/tentative-carb-id-layout.43392/
Click to expand...
Thanks.Sorry about so many posts.
 
great tables.what does umdr stand for in the columns?

Not to many posts making it easy to navigate for the IQ challenged, (takes one to know one............me), and doesn't clog up a thread with multiple posts for one set of carbs, or 2 or more pages to sift through.
 
2M's mention of the volume of your posts has to do with the fact THAT forum was set up so only people with 100 or more posts could even view it let alone post to it. After you have been here awhile you will find not everyone takes the time to figure out where to post to take advantage of the site.
That particular thread was set up as a knowledge base thread rather than a discussion thread. And those three were doing a fine job of identifying the various differences between carb years and types.
It was not a hint (subtle or otherwise) to or about your number of posts.

I did see your picture of the carbs condition. I have read your posts. So far you have used chemicals that have no lubrication properties. It could be you are fighting a corrosion problem that needs lubrication and not just cleaning.
Some things are beyond resuscitation but having spent over a year on one carb set, just to rescue a throttle body I don't throw in the towel easily. Guess I am a wait'er not a do'er.
 
Good points all.I am used to criticism from the suzuki gs forum.I dont go there anymore.They criticized me for having more than one thread, not leaving spaces between the end of a sentence, capitalization, etc.I dont sense that here. I was just kidding around. Funny reference you used. Being a waiter and not a doer. Sounds familiar.
 
Not too many posts at all Ron. As you've seen, one of the great things about this forum is that people are willing to listen, advise, pitch in and help each other when someone has a big technical struggle with their bike, like you are having with your ding-danged carbs (or should I say those f@cking carbs of yours?).

Anyhow - there have been LOTS of people with issues ranging from starters, charging systems, no-start conditions to lighting and turn signal woes - but there so darned much knowledge here that eventually all of these problems get solved and another great old bike rejoins the fleet.

As for corrections to style and grammar - our resident expert, Bob Kelly III, ( :D ) will likely be in touch shortly with some pointers for you. :laughing:

Anyhow - stick at it and remember the Latin motto of St. Lucifer Murphy - the patron saint of people who work on old machinery:

Illegitimi non carborundum

(which roughly translated means: "don't let the bastard wear you down")

Cheers,

Pete
 
Hopefully I just solved my problem.I wont post anymore about carbs for awhile.A guy from this forum,Sean, in new jersey.I just bought a set he had on a running bike for $225.Includes carbs,shipping,manifolds and throttle cable.When the ebay junk comes I will return to sender. I also will keep my current carbs for parts. Once the carbs are on and proven functional I am going to take one of the old ones completely apart and solve this mystery plus learn something.

I remember when I rebuilt the 80 gs 1000 motor.It would not turn over.Heads had to come back off, carbs,the whole thing practically. The pos front cam chain guide had popped out of the cup under the crank and was blocking the engine from turning. Once it was back in the bike ran great. But then I destroyed the wiring trying to put a fairing on. Imagine that.
 
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