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Discussion Starter · #1 ·
Hi all, so I recently rebuilt my carbs as the last step to getting my bike on the road. It ran pretty rough prior to the rebuild and was clearly out of adjustment (idled high and always lost power over 4000rpms). I made sure to follow the clymer manual, as well as the official honda manual, to the dot. Made sure the floats were .75" from the bottom of the housing.. etc. I basically did everything I could possibly do to make sure they were rebuilt correctly (Idle air screw turned 1.25 times out from the seated position..). Problem is now I can't start the bike. I def smell fuel, and after cranking (electric starters are for wussies) a few times some gas even drips out the from intakes. Tested both plugs for a spark they looked fine. Any ideas? I'd really like to avoid trailering it to a mechanic.
 

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Sensei
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Any cracks in the rubber carb "boots" or possibility of other intake side air leak?...(good seal to the carbs?).. Is the throttle butterfly open enough to pass the idle circuit fuel past it and into the intake tract? (If it closes tightly, it can block this tiny passage)
 

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Sensei
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Assuming you have good compression (160+ PSI) there is a "quicky" test to eliminate some possible reasons it won't run....If interested, I'll expound.......

As for the throttle, are you looking at the slide or the butterfly plate?
 

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Discussion Starter · #7 ·
I'm fairly sure it has compression, I'll take a ride to a local pawn shop and get a tester one of these days. The idle air screw isn't touching the slider and is all the out (the plates are closed all the way). How much should the plates be open? This may be the problem, because in all the dozen times I took the carbs on/off to make adjustments, the idle air screw was never touched (the correct adjustment is never mentioned in the book). Go ahead and expound though, it's valuable info!
 

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Sensei
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On a 360, the IDLE screw doesn't touch the slides, it rotates/stops the bellcrank.... It should be a black knob at the rear/bottom between the carbs
The IDLE/AIR MIXTURE screws are a separate entity and should be set at one turn out to begin with...... The throttle butterfly plate opens as the idle screw is turned in...it must be "cracked" open enough to expose the pinhole feed from the idle circuit (at the botton of the venturi, engine side of the carb, just below the plate......You should have seen carb cleaner blow out here when cleaning the idle passages)

Here's my "cheat" method to see IF it IS a carb/fuel supply problem:
1... remove carbs from boots, they are NOT used for this test...
2... tape the openings completely closed with duct tape and install the clamps so the tape can't get pulled into the engine....
3... Punch a 1/4" hole in each side in the tape (a #2 pencil diameter hole)
4 ...squirt 1/2 a medicine dropper (eyedropper) full of fuel into each hole
5 ...attempt to start bike... if it burps, sputters, and/or tries to run the carbs ARE the problem.... It may even actually run a short while (depends on how much gas you used...) It may take several kicks if you use too much fuel....as we have created a full-choke condition)

Let me know what happens, I suspect the idle passage in the carbs is blocked, either by mung the cleaning process has pushed further in, or by the throttle plates not being open at all or enough.....( I have also seen the tip of the mixture screw broken off by overtightening, blocking the passage)
 

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Discussion Starter · #9 ·
Thanks, great method, I'll check it tomorrow. It definitely is possible that there is still gunk in there. I removed so much orange georgia clay from carbs I was shocked (no air filters :roll: ) The Idle screw is unscrewed as far as it goes, not touching the bellcrank, so the throttle plates are completely closed. How much should the plates be 'cracked' open? Just a smidge? I'm hoping that's all that needs to be done. Everything was painted red, so there are no black knobs :? but I know what you're talking about. The idle air mixture screws were both set at 1 1/4 turns which is what clymer says. Right about now I'm appreciating the miracle of electronic fuel injection.
 
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