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Discussion Starter #1
I have been putting back together a mess of a project bike and have almost got all the kinks sorted out. I had to rebuild/clean out the carbs due to clogging and stuck throttle because it sat for so long and re-connect the majority of the vacuum lines. Problem is there is one "T" that I cannot figure out where it goes and I am not sure if that is the reason I am having idling issues. Right now the bike will start right up and run, but only at full choke. It will heat up all the way but under choke as soon as you bump the throttle it will die, and if you try and back off the choke it will die as well. I can take it to about half choke and rev the bike up some, but the throttle is not directly responsive to the RPM's so I know that I am not in full control of the motor.

So I think this could be caused by one of two things. Either I have a float stuck in the carbs causing it to only run under full choke or it is a vacuum issue. Below is a pic of the "T" that has no home if someone can identify him. Any thoughts or suggestions?

 

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Your idling problem is being caused by clogged pilot circuits in the carburetors. Take your carbs apart and clean them properly.


Where is that hose with the T fitting going? What else does it attach to?
 

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Discussion Starter #3
I pulled them earlier today and got the idle issue solved, now it will run w/ or w/o the choke. The issue I am having now is IMO a vacuum issue because it is slow to rev and slow to come down off of a rev. That hose comes off of some vacuum hookups, 2 to be exact, that are on the top back of the carbs. The loop around to the front and have what looks to be a dead end, but there is that T there that needs to hook to something. What I am not sure. Bike had a bunch of missing hoses and this is one of them. Also missing the two small hoses that connect to the bottom of the fuel tank, most likely for pressure and one for overflow. But is the pressure one possibly related to the T?
 

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Slow to come down off of a rev, typically suggests a lean running condition, which would corroborate a vacuum leak.

If you block off that T fitting, does the bike run better? I'll try to take a look at my R6 today, and see if I can identify that hose, and where is it routed.
 

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Discussion Starter #6
Have not tried because I am still missing the top portion of the airbox which the rest of that hose assembly attaches to. Another thing I noticed is that on each side of the air box it had two vacuum hoses that went to the carb, but on the right side of the airbox it had what looked to be another hose hookup that was a dead end, not sure what that is for. And another thing I was considering is if that T was for some sort of crankcase pressure, because it did have what looked to be a mesh inline filter on it and what could be a separator on it as well. Just another thought. Microfiche show the T but not what connects to it.
 

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There are no vacuum lines attached to the airbox. The airbox will have breather lines from the crankcase, and vent lines from the carbs.
 

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Discussion Starter #9
Kinda what I thought, looks like it is time to try and re-tune and sync the carbs. Any good suggestions for the kit to do that?
 

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All you need to synch carbs is a good set of vacuum gauges. As far as tuning the carbs, if the bike is stock, just leave them alone.
 

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Discussion Starter #11
It is stock. I think I have some gauges that will work and doing a little reading on how to sync them up, though confused as to where the individual vacuum lines are for each carb. Only write ups I could find w/ pics were for FI. Last couple things im going to try before I do that is get the rest of the air box because I am missing the top piece and that may play some roll, also I need to get a t-handle to tighten the carbs down because they are just slid in the rubber boots that mount them to the motor. They are tight, but I may have a vacuum leat there. Thanks for your help.
 

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On the carbs, you will notice 2 sets of vacuum lines that come out of the carbs and just attach to each other. You need to split those two hoses, to attach the vacuum gauges to them.
 

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Discussion Starter #13
on the bottom of each bowl is a drain plug as well as two inch long pieces which "looks" to have a vacuum line hook up to. Are those the spots you are referring to? I have a feeling that I am missing more parts than I originally thought...
 

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On the bottoms of the bowls, the only hoses are most likely hoses for the float bowl drains.

Do the hoses look like they are attatched to where the drain screw is located?
 

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Discussion Starter #15
Back of my carbs
Top of the carbs

On the back pics, im referring to the inch long extrusions that look like they have holes at the bottom for vacuum/fuel.
That manual book really needs to show up in the mail soon...

*edit*
reverse the labeling, I am an idiot...
 

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Those are just the drain spouts for the float bowls. Sometimes they have hoses on them to prevent gas from spilling all over the back of the motor.
 

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Discussion Starter #17
Then I must be missing something, because the only air hookups on this are the two larger pipes on the sides that go to the box, and then the two smaller pipes that connect 1 and 2 together as well as 3 and 4. Are those the ones you are referring to?
 

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Yes, the ones that connect the carbs together. The hoses should not run anywhere but to another carb.
 

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Discussion Starter #19
Yeah, I have all of those hooked up correctly then. My problem may lie in the carbs not being property snugged down to the motor. It not i'll just have to wait for the book that is in the mail...
 

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Yeah, getting to those allens is a real pain in the ass. I made my own special tool to get at those band clamps.
 
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