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Discussion Starter #1
Well, I had a slight issue(could feel it every once in awhile)shortly after I filled the tank the 1st time. So, I figured that there must some crud in the tank so I pulled the tank and cked the petcock. It was fine ? No crud at all??So, I figured maybe some junk in the carbs that just started to rear their ugly heads! So, I added some seafoam. About 3 1/2 oz(1/2 tank). Also found the rt carb intake hose had come off slightly. Fixed that. Road te4sted. Some change but still there?
CK'd the mix screws(set to 3 1/2). Then I remembered that the tank vent hose(rear of the tank) doesn't seem to go anywhere but down through the frame?
Here's the question: Where does that tank vent hose connect? Waiting till I find out to test ride..........
 

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The tank vent hose doesn't connect to anything. It's just there to direct any venting gas to the ground rather than the engine. Go ride!
 

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Discussion Starter #3
Going;-)
 

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Discussion Starter #4
Well, it's better. But still slightly there? Went thru the gears hard. Right5 to redline. Never missed a beat! But again at about 60 (4K rpm) Still slightly there??
Gonna try plugs next. AWhat's rec. plug? Irridium what?
 

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I installed NGK Irdiums (part #7803) gapped at .035. You will need an 18mm spark plug socket if you don't have the tool set that came with the bike. I bought mine at sears for $5. You'll also need an extension to get to the two deeper plugs. Took me 10 minutes, well worth the price/time spent.

See link in my signature file below for additional info.
 

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Discussion Starter #6
Just got back from the test ride with those in it. Actually, at 1st it ran worse? But I drove it a ways and seemed to improve a bit.
This is weird. Normally I'd say the hi speed needle or needles is the culprit? But I still think it crud in the carbs. I'll let that seafoam do it's thing and see what happens.:confused:
 

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mine was doing the same thing last year, at 60mph on the nose. wouldnt do it all the time but then became more and more frequent. then it started doing it at lower speeds and gears, I changed to iridiums but if I remember right it came back at 60. they mentioned to me gapping the coils I believe but it was at the end of the season and I didnt get to yet. am keeping an eye on it closely this year, let me know if you figure anything out!!!!
 

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Discussion Starter #8 (Edited)
Interesting. Did yours do it while "hard charging"? Ya know, flat out? Mine runs just fine flat out. Right up to about 90 or so. Bangin' gears all the way. Not a hiccup??
I think it's either the high speed jets(needles) or gas crud? The carbs were done in '09 'for I got it.
 

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ran through the gears fine but always around 60 it would get a little sputter, 55 and 65 was fine. I have a new agm batt, stator, rr and iridium plugs. cleaned and recharged my old air filters and it seemed to help but I do want to do the pickup coil gap adjustment and see if that cures it for good!
 

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Discussion Starter #10
I just ck'd the garage to see if there's any leaks(Had the tank off) and WALAA! Leaking from the main line. Clamp was bad. So I put on a new mini clamp and that issue's gone. However, that valve shouldn't be "live" with the bike off! Vacuum turns it on when started. Now I'm wondering if I have a vacuum leak or maybe the petcock has to be rebuilt? I did have it apart? Then again maybe the rear (it's that cyl.)carb is flooding? Or sticking closed?
Sure wish I could see under there! Or a good diagram. That I can read? Clymers doesn't really get it in this instance.
 

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check that hose that goes to the right ear!.. cut it at a 45 degree angle and you should be fine...its sounds like it is botteming out on the ear or its out of the ear and getting to much air.
 

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Discussion Starter #12
I'll ck that tomorrow and repost. Thanks.
 

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that hose is one of those crazy things.. if its out its fine untill you get to much air to it (speed) and then it stumps ya.
 

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Discussion Starter #14
Makes alot of sense. On the other hand it makes me want to rip all that plumbing outa there and simplify it!
 

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check that hose that goes to the right ear!.. cut it at a 45 degree angle and you should be fine...its sounds like it is botteming out on the ear or its out of the ear and getting to much air.
that hose is one of those crazy things.. if its out its fine untill you get to much air to it (speed) and then it stumps ya.
Makes alot of sense. On the other hand it makes me want to rip all that plumbing outa there and simplify it!
This is not an emissions control hose. It is strictly a carburetor fuel bowl vent. You do not want to "rip out" this one. Like clock152 says, cut the end off at 45* so it will not get plugged or bottomed out, but will be protected from from moving air currents when inserted in the right ear slot.:smiley_th
 

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Discussion Starter #16
Now it really make sense! Can it be seen with the ear on. Or do you have to open the filter assemb.? I pulled it away some(the rt ear) and I see a vac line fully connected? Wonder if it's the other end pulled loose?
 

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it could be botteming out on the ear houseing..make an angle cut at about 45 degrees and stick it back in.... or go all out and do and ear shave!.. more hourses and a sleaker look.. I, Like Slim, am keeping my ears after the shave and useing the for storage/accesories (cig lighter).
 

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Discussion Starter #18
Hmmmn. Went out to look for that hose. Noticed the petcock leaking!!! The more I read the more I think it's got to do with the petcock and vac lines to it. Gonna take the tank off again tomorrow and see.
 

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Discussion Starter #19
Looking elsewhere on the petcock I find a possible issue. Does the bottom line that goes to the left carb control vacuum? Anyway, should there be gas coming out of that bottom hole when the bike is not running?
From what I've read, the 2 top lines on either side go to feed the individual carbs. And the bottom line draws vacuum on the valve when running. Right?
 

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Looking elsewhere on the petcock I find a possible issue. Does the bottom line that goes to the left carb control vacuum? Anyway, should there be gas coming out of that bottom hole when the bike is not running?

From what I've read, the 2 top lines on either side go to feed the individual carbs. And the bottom line draws vacuum on the valve when running. Right?
Yes, the bottom/middle hose on the petcock goes to the vacuum source on the carb.

No, fuel should not run from that nipple at any time. Gas should only ever flow from the two nipples on either end of the petcock. Sounds like a torn diaphram in the petcock to me. Time for a rebuild kit. Hopefully it will be a quick, easy and inexpensive fix for the 60 mph stutter now.:smiley_th
 
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