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2006 CRF50 carburetor cleaning

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The air/fuel adjustment on my carburetor appears to non-adjustable, its round with one flat spot on it. When cleaning this carburetor does this need to be removed and if so how?

Can this be modified to be adjustable? If so, how?

It seems a lot of people are having trouble cleaning out the idle jet (the small tube) due to its size. I have found a drill bit small enough with using a pin vise that clean this tube out nicely. If anyone is interested in the size let me know.

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I just finished cleaning my neighbors bikes up that have sat with gas in them for the last two years....It wasn't pretty the inside of the carb. was coated with varnish and every port was clogged. After half a can of gumout and small wire brushes I managed to get the innards clean. The main jet was no problem as well as the float valve, but the small idle jet was totally clogged, this little tube is pressed in to the carb. body, I managed to get it out by grabbing it with a vise grip and gently tapping it up and out to clean it. Using a small .025 drill I have, I finally got it through the other side, which took me nearly half an hour. I re-installed it by "gently" tapping it back in place with a small piece of wood so I wouldn't distort the orifice again. In short, it runs like a champ now, and the owner is pleased.

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I just got a 2007 CRF50 back together and cannot get it to idle. I took the carb apart and cleanded the main jet and the bowl, now it looks like I need to clean the small idle jet as you have done. I'm not a carb guru, any tips on what and how to clean besides what you have listed above? Any help would be appreciated. Here is a pic while adjusting the rear brake, she gets it Christmas!!

DSCN3843.jpg

So far have replaced rear shock (was blown when I got it), new tires and tubes, new seat and plastics. I notice the front tire and the fender and bars don't line up, any way to tweak them so they are straight? Or do I need new forks?

Thanks

Jim

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I just got a 2007 CRF50 back together and cannot get it to idle. I took the carb apart and cleanded the main jet and the bowl, now it looks like I need to clean the small idle jet as you have done. I'm not a carb guru, any tips on what and how to clean besides what you have listed above? Any help would be appreciated. Here is a pic while adjusting the rear brake, she gets it Christmas!!

DSCN3843.jpg

So far have replaced rear shock (was blown when I got it), new tires and tubes, new seat and plastics. I notice the front tire and the fender and bars don't line up, any way to tweak them so they are straight? Or do I need new forks?

Thanks

Jim

As far as the idle jet you'll need to do as I did with a drill bit or replace the jet. The forks just sound twisted which is an easy fix, stand in front of the bike with the front wheel clamped between your legs, grab the bar and yank it to which side will align the fender to the wheel. By the way, pretty little bike, she's lucky to have a dad like you.

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Thanks, I will pull the carb and get to work getting the idle jet out. I will also tweak the forks and see if I can get them straight. Thanks again.

Jim

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As an FYI, if you remove the pilot jet and/or break it, it is NOT replacable, you have to get another carb.

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As an FYI, if you remove the pilot jet and/or break it, it is NOT replacable, you have to get another carb.

If you do break the idle jet off, take it to any machine shop and they would be happy to drill the jet out for you. I'm willing to bet your local Honda dealer would install the new jet for you.

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I'm willing to bet your local Honda dealer would install the new jet for you...

In the microfiche diagram below, the red arrow indicates the pilot jet. As plainly seen, there is no reference number or authorized 11-digit Honda part number assigned to it. It is NOT a replacable item. You cannot walk into your local Honda dealer and pick up a new jet that has no assigned part number. If you break or mangle it while removing it, you have to get another carb.

CRF50carb-1.jpg

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Thanks for the info dirtbkr188. I will soak it overnight and then try to clean and use compressed air. I appreciate the info and will let you know of any progress or lack! Can't take a chance on breaking this thing this close to Christmas.

Thanks again

Jim

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While cleaning the carb after the soak, be sure to spray some contact cleaner through both of the holes on the airbox end of the carb. The one at the 7 o'clock position is for the pilot jet, spray should exit through the pilot jet and the air screw hole. The hole at the 6 o'clock position is for the main jet passageway, the spray should exit the center hole in the carb where the jet needle drops into, and also the main jet end. Follow up with compressed air through both holes.

101_0074-480.jpg

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Quick question, I have the carb apart and have removed the main jet, the idle screw, the bowl gasket and the rubber o ring where it matches up to the intake spacer. Without having the tool to remove the air adjust screw (the round one with the flat side), either, 1. Can I soak it in cleaner without removing it? or 2. How can I remove it to better clean the carb? Thanks

Jim

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If you can remove the air screw somehow, some guys cut a slot in it so it can be reinstalled and adjusted with a straightslot screwdriver. It would help if you are able to back it out some, to allow the contact cleaner to pass through the passageway. If you can't remove it at all, you may get lucky and the passageway may be clear.

You can soak it with the air screw in place, there is no o-ring on the end of it.

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Not sure what the screw head is by your description (sounds like a flathead screwdriver) but it's not absolutely necessary take it out. Only air passes through it before it reaches the slow jet, it doesn't really have anything to get clogged up. Sounds like your biggest concern is that slow jet

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Sam, the screw I am talking about the head of it looks like a capital letter D. I guess the 04 and earlier had a flat tip. I am soaking it overnight and will take it out tomorrow afternoon and blow the passages out. Thanks Dirtbkr and everyone wlse for helping me with this. Im not a carb guy (yet)

Thanks

Jim

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Here's a pic of a pre '04 OEM Honda 13mm carb for the Z/XR/CRF50 bikes. You can see the slotted air screw to the lower left of the idle adjust screw.

101_0032-1.jpg

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Thanks for the info dirtbkr188. I will soak it overnight and then try to clean and use compressed air. I appreciate the info and will let you know of any progress or lack! Can't take a chance on breaking this thing this close to Christmas.

I find many people use compressed air for carb cleaning - IMHO it's a terrible practice. It instantly evaporates the solvent and re-dries whatever remains. I have had great success with cheapo aerosol carb cleaner. I saturate all of the passages well, let it sit for a while (soaking as you mentioned is even better), then blow out with the aerosol cleaner. The spray can (w/ little tube) does the same thing as compressed air in that it blasts out gunk, but replaces the solvent as you go. I don't dip, use only the $2 walmart cab cleaner, and I've never had to clean a carb twice. Even cleaned a 4-stroke carb that sat with E10 and the petcock open for 2 years (seriously icky).

JayC

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Sam, the screw I am talking about the head of it looks like a capital letter D. I guess the 04 and earlier had a flat tip. I am soaking it overnight and will take it out tomorrow afternoon and blow the passages out. Thanks Dirtbkr and everyone wlse for helping me with this. Im not a carb guy (yet)

There is a special tool for that stupid thing. You might be able to take it out with needle-nose pliers. Once you get it out (however you can), then cut a slot with a dremel tool so you can use a screwdriver from then on.

JayC

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Thanks for the tip JayC. I will try that. I did dip it overnight, washed it off, sprayed carb cleaner throughout ensuring to get any hole I could and rebuilt it. Put it on and it is a big improvement. Since my daughter was home today, I wasn't able to warm it up and completely adjust yet. That will be in a couple of days. Thanks again to all for the help.

Jim

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In the microfiche diagram below, the red arrow indicates the pilot jet. As plainly seen, there is no reference number or authorized 11-digit Honda part number assigned to it. It is NOT a replacable item. You cannot walk into your local Honda dealer and pick up a new jet that has no assigned part number. If you break or mangle it while removing it, you have to get another carb.

CRF50carb-1.jpg

I should have clarified my reply, my Honda dealers mechanics would replace it for a small price. That's why they're still in business and not rape the customer.

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Got everything cleaned good, removed the d shaped screw and cut a slot in it for a flat blade screwdriver.

The bike cranks without the choke on when its cold which is unusual. If you turn the choke on it cuts off. It runs like a two cylinder engine running on one cylinder. When you are accelerating it smooths out but as soon as you level out it starts back running rough. When I was cleaning the main jet, before I knew what it was, I may have got a little rough with it considering it was stopped completely up. This bike has never cranked cold without the choke on. I'm thinking I may have openned the main jet up some causing it to get too much gas. Any opinions

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