Post rejetting question

Peanut, I would normally be working on it during bad weather, but it's close to Christmas and my wife never takes it lightly, even though my youngest is 28 and we only have "Grand Dogs". Plus I still work 2 and a 1/2 jobs while I still can. I'm also supposed to have a farm table built for the kitchen by the 20th.
 
As Griz said, if the needle is worn, the jet probably is too. It had to be rubbing on something to wear and the jet is the most likely candidate. And the problem is, the part it would most likely be rubbing on is the metering orifice. That would wear it bigger and richer. If you look down into the top of the needle jet, you will see a small step about 1/8" down in there. That is the metering orifice that the needle fits into and works through. It's quite large compared to the metering orifice you find on a main or pilot jet but none the less, it is a machined hole that is precisely sized. When worn by a needle, often that wear is on one side only. Part of the "step" you see when looking down in there will be worn away and the hole will now be oval shaped instead of round.
 
Marlin72xs said:
Peanut, I would normally be working on it during bad weather, but it's close to Christmas and my wife never takes it lightly, even though my youngest is 28 and we only have "Grand Dogs". Plus I still work 2 and a 1/2 jobs while I still can. I'm also supposed to have a farm table built for the kitchen by the 20th.
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by the 20th yikes ? :eek: you'd better get ya skates on then :)
 
peanut said:
I agree Marlin it is very frustrating when posters ask for help and then the thread ends with no posted solution or outcome. I always try to find out the outcome in order to close threads when I can so it can inform future searchers that arrive at the thread

What makes things both confusing and frustrating is when posters ask a question about their particular bike or component problem right in the middle of another posters thread.
When responding to someones request for information or advice we invariably look to the first post of the thread to aquaint ourselves with the model year and components , modifications and all the other vital information needed to get a full picture of the issue so that we can respond.

If someone hyjacks another members thread,...then all the information, specifications and advice gets mixed up and eventually 3 pages on, nobody is clear which information and advice is associated with which bike owner or particular problem without re-reading the entire thread .

Your bike has BS34 carbs as stock and Mikes bike had BS38s Whilst they are both CV carbs that operate in the same manner , they are different carbs in terms of jetting and component specifications.

It is always better to request advice or information about issues with ones own bike by starting a separate dedicated thread so that there can be no confusion.;)

if you are not going to ride your bike or work on it due to the cold weather , why not remove the carbs and strip and clean them in the house ready for when the weather improves. Thats what i do every Winter. I hate working in a cold drafty shed or garage when I can work in the warm comfort of my sun room with coffee and cake on hand lol:)
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Nice rant and a fair enough one as well:thumbsup:.............Shame you didn't finish your 3 carb threads though;).........Marry Xmas
 
Re. the NJs, they're sized in alpha sequenced groups, larger jets designated by later letters. Within each letter group, jets are designated by even numbers from 0 to 8, except for 5. A numeric step of 1 (from 4 to 5, for example) indicates a difference of .0002". The NJ is the component with the strongest effect on cruising range fuel consumption. It doesn't take much wear at all to make a bone stock XS650 start sucking down a gallon of fuel every 35 miles.
 
650Skull said:
Nice rant and a fair enough one as well:thumbsup:.............Shame you didn't finish your 3 carb threads though;).........Marry Xmas
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well shame on me !:)........seeing as you are obviously so well acquainted with all my posts perhaps you'd kindly let me have the links to the 3x threads in question and I'll correct my omission directly ;) Merry Christmas
 
And Merry Christmas to you, Skull. It's good to have you back. I had dinner at the Outback Steak house last week and I thought about you.

5twins, yes the needle, has about a 3/4" shiney spot on one side. Hey, my little shaker shook the needle off my new tachometer.

Peanut. My main job is a Home Inspector, but when not inspecting, I'm a substitute teacher at the high school where my wife works. I also work one night a week at Dick's Sporting Goods fixing golf clubs and stringing rackets. I'm really only there for the 25% discount. Presently, I'm an assistant sub for a wood shop class. The teacher was fired. I have all the tools I need at my disposal. It's still gonna be close.
 
grizld1 said:
Re. the NJs, they're sized in alpha sequenced groups, larger jets designated by later letters. Within each letter group, jets are designated by even numbers from 0 to 8, except for 5. A numeric step of 1 (from 4 to 5, for example) indicates a difference of .0002". The NJ is the component with the strongest effect on cruising range fuel consumption. It doesn't take much wear at all to make a bone stock XS650 start sucking down a gallon of fuel every 35 miles.
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Yes. I agree. I've been running the NJ at the #3 slot for the past 4 years and when I changed them to #4, I went to reserve at ~120 miles when normally ~150 miles. Well, I have some spare 75 carbs with only 12K miles. A quick visual shows little or no wear, but the exteriors are dirty as hell. I just may clean those suckers during this cold spell and put them on. It'll save me a few bucks. Besides I like the wide open throat on the newer carbs. They may enhance the porting I did.
 
Hopefully the needle jets in those '75 carbs are OK because you can't get them. None of the original, genuine BS38 needle jets are available but you can get repros for all except the '74-'75 set. The short version of the Z-6 needle jet used in that set is not available anywhere that I know of.
 
Yes, many times that's all that holds them firmly in there. The needle jets on my '78 carbs practically fell out by themselves when I removed the float bowls. The o-rings were really shot and new ones fixed them right up.
 
My new jets and needles came in yesterday. Yahoo! Unfortunately, I'm 350 miles away visiting for New Years! Woopy, fooking do! I could have been grinning on my bike whilst cruising up Blood Mountain. Now, I have to wait till Wednesday. Oh, well. Happy New Year everyone! Be safe, ride safe and keep on ridin'!
 
Here's a weird one. About 2 months ago, I start her up in the morning. Starts great as usual, now, give it some gas and it sputters and runs like one side is missing. Give it gas and it jumps and sputters more. I'm thinking, plug going bad, plug wire shorting, even worse, the Pamco is gong bad. Well, I did change the cam seals 3 months ago, but the left one is leaking again. So I think, hmmm, is the oil shorting out the Pamco? Cleaned it up, checked the plugs, swapped the coil wires and, same thing. Spark is all good, so I went to the carbs. Pulled the filters and boxes.
Stuck my finger in the carbs to check the slides and guess what I found? :wtf:
 
I found that I was dreaming and my wife said, "Not now!" Story of my life! LOL!

But seriously, folks, I found the slide 1/2 way up and the needle was out of the jet. How can this happen? Plus, it happened on startup. I know because it ran fine before I parked it the day before.

OK, I said to myself, it's a fluke. Road it for another 1000 miles and replaced the left cam seal and proceeded to start her up and have a nice ride, and...., (dramatic pause), it happened again. Weird huh?
 
The needle jet can't fall down, the float bowl traps it in place. I don't think the slide will lift high enough to allow the needle to come out of the needle jet. Maybe you've got some incorrect parts in there (needle or needle jet), or maybe things are assembled wrong (needle retainer washer). What year carbs, what needle, and what needle jet?
 

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