Honda Rebel Forum banner

1 - 20 of 25 Posts

·
Registered
Joined
·
26 Posts
Discussion Starter #1
I cleaned the carb, replaced the spark plugs, changed the fuel filter and put in a new battery. Things are definitely running better but not where I'd like them. I have to have the choke/enrichment at about 1/2 and based on my portable tach, it will idle around 1400 or so. However, if I take off just a little of that choke, it will die immediately. It's like an on/off switch. No slow drop of RPM and then a shut off, just an immediate shut off. It will even do this with some throttle applied and above 2000 RPM. Only if I have a ton of throttle, will it stay going but back off the throttle a little and again it immediately drops dead. Does this still sound like the idle jet (even if it looked completely clean) or is there anything else?
 

·
Super Moderator
Joined
·
29,136 Posts
Choke is usually required until the bike has traveled several miles. Start it, let it idle for half a minute or so to get the oil circulating, and ride it. Ease the choke off gradually as the engine warms. If it still doesn't act right, I'd guess the carb is still dirty. There are a lot more places in the carb than the slow jet that have to be spotless for it to function properly.
 

·
Registered
Joined
·
26 Posts
Discussion Starter #3
I let the bike idle for a good 20+ minutes but did not take it for a ride. It was plenty hot though and the choke acted the same when cold as when hot. I will of course check it again when I go for a ride but it sounds like perhaps I should have done a rebuild versus a clean. It is much better than prior but still disappointing.
 

·
Super Moderator
Joined
·
29,136 Posts
Not sure what your definition of a rebuild is, but the jets don't need to be replaced, just cleaned. Ditto for the diaphragm if it hasn't shrunk or torn. How did you clean the carb? Full disassemble and soak in Chem Dip, carb spray, or something else?
 

·
Registered
Joined
·
26 Posts
Discussion Starter #5
From the kits I saw it was gaskets and jets. I assumed that was standard but your post seems to indicate that it is not. I fully disassembled the carb and soaked it in Chem Dip. After I rinsed each part off in water and used compressed air for further cleaning and drying. Additionally for the jet holes I used some fishing line as I understood that using metal could be detrimental.
 

·
Super Moderator
Joined
·
29,136 Posts
You can purchase kits with just the gasket, gasket and O-rings, gasket, O-rings and jets, and even more. All that is usually needed is the gasket and a new float valve. Chem Dip is good stuff, but it takes a while for it to dissolve the crud that develops in carbs that haven't been drained before storage. The longer it is allowed to soak, the better the chances it will get completely clean. 48 hours is the minimum I recommend, and a week is even better.

Looking on ebay, it appears the kits with gaskets, jets, and other parts are the least expensive. Last time I ordered a kit, it wasn't that way. I would get one of those and use just the rubber parts. I don't recommend using the needle supplied with those kits as they differ slightly from the OEM needle, and I've never seen a needle that needed to be replaced. https://www.ebay.com/itm/For-Honda-Rebel-250-CMX250C-1986-2012-Carburetor-Rebuild-Carb-Repair-Kit-US/164157621428?hash=item26388e84b4:g:zPUAAOSwHk9ei-Zp

https://www.ebay.com/itm/For-Honda-Rebel-250-CMX250C-1986-2012-Carburetor-Rebuild-Carb-Repair-Kit-US/164157621428?hash=item26388e84b4:g:zPUAAOSwHk9ei-Zp
 

·
Registered
Joined
·
26 Posts
Discussion Starter #7
These are the kits I saw as well. I am loath to take the carb out again as it was such a nightmare. I'll ride it a bit to see how things settle and then determine next steps. It is a lot better but I may just be stuck having to use some choke.
 

·
Registered
Joined
·
115 Posts
I wouldnt ride it choke on all the time, youd get crap mpg, excess carbon on valves/piston, and over time its not good for the engine. my 250 will cold start no choke, no problem; so from what you described it sounds like theres still crap in your idle circuit. you could try seafoam in the tank but itll only work if whatever is in there is already loose. with carbs you want to just get it done right once, then make sure it doesnt get bad again. Get a can of berrymans chemdip at the auto parts store, take everything apart (make sure no rubber is in there & take lots of pictures) and soak that thing for 24-48 hrs depending on how much crud ya got. then get air compressor with rubber tip and blow the crap out of every hole you can find. dont clean it with water after, I made the same mistake, get laquer thinner and go from the chemdip to a tin tray of laquer thinner; water will re-solidify the crap. id soak the jets and bowl too, blow those out and reassemble with new bowl gasket, bowl drain screw o-ring, a/f screw seat. use the old jets, the ebay carb kit i got came with wrong jets. use service manual to tune a/f mix. the more times you take it apart, the easier it gets; and its basically the same procedure on all bikes. my 450 dual carbs took probably 4-5 times off the bike to get em fully cleaned... looking back I shouldve just done it right once. but now i'm like a carb pro :) good luck!
 

·
Super Moderator
Joined
·
29,136 Posts
Daren4ch, I have to differ with you on the water rinse causing things to solidify in the carb. I've done quite a few Rebel carbs and never had one malfunction using that procedure. If there is any Chem Dip left in the carb, it will dry and leave a residue.
 

·
Registered
Joined
·
26 Posts
Discussion Starter #10
A follow-up question here. Just took her out for a ride and found the same issue described above. I understand I may have to clean the carb for a second time and maybe let it sit in the chemicals for a bit longer; however, I also wonder if there can be anything with the choke itself? What seems odd is how 1mm is like an on/off switch. It's not as if it starts to get rough and then conks out. Just the slightest tap on the choke level and it will immediately shut-down. Is there anything I may have done incorrectly when reinstalling that cable or is this just definitely the carb again?
 

·
Super Moderator
Joined
·
29,136 Posts
The choke/fuel enricher on every Rebel I've had was very temperamental. I couldn't move the lever in either direction while the bike was idling, or it would die. Once riding, the lever could be gradually pushed off as the engine warmed. But trying to do it before then resulted in a dead engine. So from what you say, it may just be the enricher doing what it does. However, if you have to keep the enricher at least partially engaged for the engine to run right, even after it has warmed, I would guess a less than completely clean carb.
 

·
Super Moderator
Joined
·
29,136 Posts
FWIW, one member here soaked his carb five times before he got it clean. That's the record, AFAIK. But the longer you can let it soak, the more likely it will come out clean. Any chance you could get access to an ultrasonic cleaner? They clean carb parts in an hour or less.
 

·
Registered
Joined
·
26 Posts
Discussion Starter #14
If I had to do it more than one more time, I think I'd take it to the local shop. I could buy an ultrasonic but it's not like something I would use for anything else. I don't mind leaving it in the dip but the thought of taking it off the bike again gives me chills. Once off it was easy but that damn air box when trying to pull the carb back. No thanks. Perhaps if I had a lift that would let me stand versus the one I have which lifts it only an inch or two off the ground. Maybe it will be like childbirth is for women. They forget how painful it is and go on to have another. Perhaps I'll experience that in carb form at some point....
 

·
Registered
Joined
·
115 Posts
you could use the ultrasonic cleaner for many things... that is if youre like me and have many project going at once :) carbs on other bikes, brake calipers, fuel injectors, basically anything with small passageways that would otherwise not be easily cleaned. and its not limited to just motorcycles/cars; jewlery, tools, firearm parts, etc. For best result cleaning carbs, berrymans chemdip in the ultrasonic cleaner for an hr (watch it the whole time and dont use the heating element) you could also use warm soapy water. and as far as the airbox, use a heat gun on the rubber boot going to the carb (not too long in one spot and on low setting) and it should easily pull back into the airbox making removal easy peasy.
 

·
Super Moderator
Joined
·
29,136 Posts
WD-40 also helps to lubricate the rubber tube when sliding it into the airbox, and it won't hurt rubber. Folding the tube in on itself also simplifies things. After you've done it several times, it's not that hard - but hope you only need to do it once more!
 

·
Registered
Joined
·
1,912 Posts
Won't run without the enricher -> suggests its not getting enough fuel into the cylinders.
the fact that the enricher makes it work suggests the petcock and fuel lines are fine.



1. air leak at the carb/mainfold gasket location.

2. air leak around the vacuum piston flange.

3. mixture screw turned in too far (lean), or the o-ring was left in during cleaning with chemicals and has melted & clogged the idle passage.
4. float needle stuck in the 'up' position

5. jets could still be clogged but one of the above is more likely...


often the '5th cleaning' that some folks find finally fixed it turned out to be correcting 1-4
 

·
Registered
Joined
·
6 Posts
Wow. This thread is straight up what I needed to read as my symptoms are the exact same.
my 450 will run only with the choke on and the bike idling. Once I try and give it some gas it dies. If I take the choke off (after 20+ minutes) It also dies.
Looks like I have to go through all that work again to get he carb off and then cleaned up good. Sigh, maybe it will be a bit easy this 2nd time...
 
1 - 20 of 25 Posts
Top