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Discussion Starter · #1 ·
Just as the title says, I finally rebuilt my carburetor after about a year of the bike sitting there. Originally I only had an issue with accelerator pump, the bike would idle fine but would try to die anytime you gave it some throttle. I rebuilt the carb shortly after that issue popped up with no luck, the issue remained; life got in the way and I've just now been able to work on it again about a year later. I discovered that I had missed one of the channels when cleaning the accelerator pump and got it cleaned up with some carb cleaner. I got a carb kit and replaced just about every O-ring and jet that came with the kit; I also replaced the vacuum piston as the diaphragm had shrunk on my original one. I put everything back together, emptied the old gas and gave it some fresh gas.

On the first start after putting everything together, I didn't realize I had left the choke all the way on (I typically don't have to use it) and attempted to start the bike. The bike ran for 1-2 seconds at most before dying. At this point, I realized the choke was all the way on so I turned it off, but no amount of using the starter, adjusting the choke, or trying to bump start the bike would get it going again. I assumed I had flooded the engine so I left it to try again the next day. The next day I tried again with similar results, I tried starting it without the choke first with no luck; I flipped the choke all the way on and it ran again for another few seconds before dying again. I followed the instructions to calibrate the pilot screw, screwed it all the way in and backed it out 2 & 3/4 turns as another thread suggested with no results. I also tried changing my spark plugs as I had already intended on changing them anyways but that didn't work either.

At this point I have no idea as to what this issue may be. I assume I'm getting air, fuel, spark, and compression if the bike is able to run for a little bit at a time. Is there some kind of carb adjustment I'm missing or something like that? Thank you for reading and for any potential help you provide!
 

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I have found that no fuel and flooded act pretty much the same on these bikes. There is a narrow band in between where the engine will run happily. Not to doubt your findings, but it wouldn't hurt to verify spark. For air I would make sure you have a good seal between carb and intake. For fuel... what was your process for cleaning the carb? You may not be done with that.
 

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Discussion Starter · #4 ·
I have found that no fuel and flooded act pretty much the same on these bikes. There is a narrow band in between where the engine will run happily. Not to doubt your findings, but it wouldn't hurt to verify spark. For air I would make sure you have a good seal between carb and intake. For fuel... what was your process for cleaning the carb? You may not be done with that.
Originally, I let all of the pieces of the carb soak in some Chem-Dip for about a day and then sprayed every jet or I could find with a can of Carb Cleaner. After starting to work on it again, I let the main body of the carb sit in the Chem-Dip for at least a couple more days as the accelerator jet (spray nozzle?) was extremely clogged. I tried to do my best making sure anything I sprayed into was clear so I feel pretty confident that its clean.

I will verify spark when I get home from work and the seal when I get home from work. The O-ring that I replaced that sits between the Carburetor and the engine was definitely thicker than the one I pulled off of it, could that be causing issues?

Thank you for your reply!
 

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My thought was also a possible air leak between the carb on the intake side.
I know it's not the best method but, if you try starter fluid does it fire? At least that way you have proof positive that the spark plugs are firing.
 

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also check the compression - it may have run a few cycles and then stuck a valve open
 

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I don't know of any Rebel that will start on full choke. 1/3 to 1/2 is the maximum for mine. Any more and it won't start.
 

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doubt thicker O-ring would cause any problem as long as connection between intake and carb is sealed..
any more than 2/3 enricher/choke kills my engine, seldom have had to use enricher/choke with temperature above 45°F..

I assume you drained all old gas out and have fresh tank full..
 

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Discussion Starter · #9 ·
I unfortunately didn't get the time yesterday to look at the bike for more than a few minutes.

My thought was also a possible air leak between the carb on the intake side.
However, I was able to verify that the rubber boot between the Carb and intake was in place, at least on the carb side. I assume my filter is in a good place as its pretty hard to get that wrong. Is it possible my boot is shot? The thin flaps that surround it must have disintegrated in the sun as they fell off immediately as I was putting everything back together, but I didn't see any cracks or anything that would cause it not to seal. I assumed that, at worst, I would just be getting some unfiltered air into the engine; would a shot boot not make it run?

doubt thicker O-ring would cause any problem as long as connection between intake and carb is sealed...
I assume you drained all old gas out and have fresh tank full..
I would think that the connection on the engine side is good as the o-ring fit perfect besides the thickness. The thickness does create a very small gap so that the carb body doesn't really contact the gasket, but that shouldn't be a problem if it seals with the o-ring right?
As for the gas, I did indeed drain all of the old gas out, but I only put about a gallon of fresh stuff in as I don't have a fuel can bigger than that.

I have yet to be able to verify spark yet, I will hopefully get to check after work today.
 

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amount of gas shouldn't be a problem..
some folks don't consider old gas as being a problem and why I mentioned it..
if o-ring sealed its sealed.. I believe gasket was designed as a heat barrier rather than for sealing..
 

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Discussion Starter · #11 ·
I finally got a chance to work on it. I have verified that there is indeed a spark in both cylinders. I double checked my intake, both the boot and the filter seemed good and unobstructed in any way.

The bike did the same thing as before, it ran and sounded perfect for a second or two at max and then died again. I tried setting the choke at halfway and other points as others have suggested with no luck.

I am now going to go pick up a compression tool as 01 has suggested and check that.

Thank you everyone for your suggestions!!
 

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Discussion Starter · #12 ·
also check the compression - it may have run a few cycles and then stuck a valve open
I picked up a compression measurement tool but I'm an idiot so I didn't think to make sure any of the adapters would fit in my bike. This one will probably have to wait, I can only handle embarrassing myself in front of AutoZone employees so many times in one week.

My thought was also a possible air leak between the carb on the intake side.
I know it's not the best method but, if you try starter fluid does it fire? At least that way you have proof positive that the spark plugs are firing.
I got some starter fluid while getting the compression tool, and it worked! The bike started up and the idle was extremely rough, but I was able to keep it running for a good 5-10 minutes this time with some throttle input. Thank you for the suggestion!

I'm assuming if my idle is rough and the thing will barely start, I'm likely still facing issues in my carburetor right? I guess I just need to leave the damn thing in chem-dip for a week or two or something.
 

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If you know somebody with an ultrasonic cleaner it's a whole lot faster and better.
Some here have even used their wife's ultrasonic jewelry cleaner!
 

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Sounds like carb running too lean. Pull carb off and take time cleaning it. Make sure float level is correct(found some needles for the needle and seat too long as supplied in aftermarket kits) roughly check how much fuel is in float bowl before draining it. stick thin piece of wire brush fiber to verify jet is not clogged. verify gas flow to float bowl from fuel line.. Seal intake with Honda bond if any doubts on sealing....I`ve had to redo carb cleans many times...because of hast and not verifying part is clean
 

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Just as the title says, I finally rebuilt my carburetor after about a year of the bike sitting there. Originally I only had an issue with accelerator pump, the bike would idle fine but would try to die anytime you gave it some throttle. I rebuilt the carb shortly after that issue popped up with no luck, the issue remained; life got in the way and I've just now been able to work on it again about a year later. I discovered that I had missed one of the channels when cleaning the accelerator pump and got it cleaned up with some carb cleaner. I got a carb kit and replaced just about every O-ring and jet that came with the kit; I also replaced the vacuum piston as the diaphragm had shrunk on my original one. I put everything back together, emptied the old gas and gave it some fresh gas.

On the first start after putting everything together, I didn't realize I had left the choke all the way on (I typically don't have to use it) and attempted to start the bike. The bike ran for 1-2 seconds at most before dying. At this point, I realized the choke was all the way on so I turned it off, but no amount of using the starter, adjusting the choke, or trying to bump start the bike would get it going again. I assumed I had flooded the engine so I left it to try again the next day. The next day I tried again with similar results, I tried starting it without the choke first with no luck; I flipped the choke all the way on and it ran again for another few seconds before dying again. I followed the instructions to calibrate the pilot screw, screwed it all the way in and backed it out 2 & 3/4 turns as another thread suggested with no results. I also tried changing my spark plugs as I had already intended on changing them anyways but that didn't work either.

At this point I have no idea as to what this issue may be. I assume I'm getting air, fuel, spark, and compression if the bike is able to run for a little bit at a time. Is there some kind of carb adjustment I'm missing or something like that? Thank you for reading and for any potential help you provide!
I had to do the same thing,had very simular problems it could be as simple as your carb is still dirty. Also check your a airfilter and make sure there's no leak that was a 2nd issue I had, I hope you get it figured out.
 
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