clogged pilot jet on a CRF50 - Success!

[Ender_]

I have a stock 2008 CRF50 and I've been battling with a common problem on these things - the pilot jet gets clogged up.   You can tell because the bike will usually run OK but just won't idle at all, and it's impossible to adjust it out.  I tried all the usual stuff, soaking the carb, compressed air, clean it with wire, spraying with a can of carb cleaner, etc.   Even a trick I saw on this forum about heating it up with a lighter.   Nothing would work - it seemed like whatever was in there was pretty solid - when I tried using wire, it just stopped cold when I tried to feed it through, just like it was hitting something solid.  

 

I was just about to order a replacement carb when I read a few posts about guys removing the pilot jet, even though it's pressed in.    A few people warned that you may completely ruin the carb trying that, but I was already on the verge of replacing the stupid thing anyway, so I figured I'd give it a go.

 

So, I lightly clamped a set of vise grips to the jet, and gave it a light tap, and I'll be damned if that thing didn't just pop out - easy as that.  Here I'm just about to give the vise grips a light tap with the hammer  (note the carb is just sitting on the vise, not clamped in):

 

 

Here's the jet, just after it came out:

 

 

After I got it out, I let it soak in carb cleaner for 30 minutes or so, then got after it with more cleaner, and a small piece of wire.   I FINALLY started making some progress with the wire, then soaked it some more, then some compressed air, etc, etc.   You've never seen a grown man so happy to see this:

 

 

After I worked the wire in and out and was sure it was clean, I put it all back together by lightly tapping it back in:

  

 

 

I put it all together and it runs like a champ - the kiddos rode it all afternoon.   So, if you're working this same issue, I hope this is some help.   The keys to making this work for me were removing the jet so I could really get to cleaning it, and also using the right kind of wire.   Someone in a another thread suggested using a single strand from a brake wire - that's what did it for me.  (I actually used a piece from a bicycle shift cable, which is about the same thing)   I think all the other wire I tried (electrical wire, mostly) was either too big, or just not strong enough.   

 

Many thanks to the folks who've posted suggestions on this topic here on ThumperTalk - reading through all that was a big help.  

 

[Go Big Red]

you are a brave man.  I have read that also, but was too chick s*&t to try it.  I am guessing it slipped back in there with no problem and is doing fine.  Fortunately for me a ton of carb cleaner and air worked.

[arthur6]

GREAT to hear

99.99999% of bad idle issues are form a blocked Pilot Jet.

It's VERY easy to do but can be intimidating.

Once you do one... and the bike runs great, you're hooked... you'll get all your friends bikes running and feel like a king.

I can't begin to count the bikes I've bought and re-sold for a quick profit, seller said it didn't run, needed the carb "rebuilt", etc... Bring the bike home, clean the Pilot and it's fixed.

Same for a bike "needing" a Clutch.... adjust the cable slack...(Doesn't apply to these small Hondas tho...)

My 2 ¢

Also - SUPER GREAT PICS - Thanks

Edited September 29, 2013 by arthur6

[somethingnuw]

thanks for the post... not the same bike but i have an 1987 honda xl185 that needs "carb rebuild"  has anyone tried pinesol?  Yes the house hold cleaner... its all over youtube just wondering if it's worked as it says on pinesol not to use with aluminum

[dirtbkr188]

thanks for the post... not the same bike but i have an 1987 honda xl185 that needs "carb rebuild"  has anyone tried pinesol?  Yes the house hold cleaner... its all over youtube just wondering if it's worked as it says on pinesol not to use with aluminum

Click on the link and read away...

 

https://www.thumpertalk.com/topic/917696-carb-cleaning-with-pine-sol-linkpics/

[Go Big Red]

Click on the link and read away...

 

https://www.thumpertalk.com/topic/917696-carb-cleaning-with-pine-sol-linkpics/

I might have to try that trick for the little 50.  IN the mean time I finally was able to fab up the 70 carb to the 50.  Holy crap what a difference.   this has to be the cheapest upgrade I have done to any bike for the extra power i got.  Now to cure the smoking.  I think I have my compression rings backwards.

 

Until then, pine sol for the old 50 carb!!!!!

[mjwwf5]

I might have to try that trick for the little 50. IN the mean time I finally was able to fab up the 70 carb to the 50. Holy crap what a difference. this has to be the cheapest upgrade I have done to any bike for the extra power i got. Now to cure the smoking. I think I have my compression rings backwards.

Until then, pine sol for the old 50 carb!!!!!

I'm still in progress for my 70 carb fab. Are you running stock jetting? And what exhaust pipe?

Edited January 7, 2014 by mjwwf5

[Go Big Red]

I'm still in progress for my 70 carb fab. Are you running stock jetting? And what exhaust pipe?

Send me a PM.  I have a ton of info for you.  Just got it done and together today.  Took it for a test ride and about fell off laughing so hard.  A lot more juice for what ended up being a free mod since I had the good top end for the 70.

[MorganM]

I have a stock 2005 CRF70 carb ready to mount on a stock '12 CRF50. Would love to see this info too...I've read it's a bolt on, but also read it requires some tweaking of the throttle cable or raising of the tank.

In the meantime, I have a jet for the stock carb and a billet exhaust tip...

[MorganM]

BTW- thanks for the thread! I was cleaning up an 81 CT110 a few days ago and it also had a press fit pilot jet. Pulled it out, cleaned it, and pressed it back in- worked like a charm.

[Go Big Red]

I have a stock 2005 CRF70 carb ready to mount on a stock '12 CRF50. Would love to see this info too...I've read it's a bolt on, but also read it requires some tweaking of the throttle cable or raising of the tank.

In the meantime, I have a jet for the stock carb and a billet exhaust tip...

So, between two of us, there are two options.  One is to buy a custom manifold from Fast50s.  Not sure of the price, but mjwwf5 has those details.  I am surre they can also sell you a throttle cable with the correct carb cap.  50s and 70s have different caps and the stock cables will not swap out.

 

The route i went was just fit the old manifold, use the stock 70 cable on a Fast50s billet throttle housing, and hack the heck out of the stock airbox to make it fit.  Mine doesn't look that clean, but it works and its cheap.  As far as raising the tank, you can shim the front and rear with a few washers.  this will give you throttle cable a little more room where it comes out of the carb.  The way I have mine is a tight fit, but most of the interference is from the frame.

 

either way, great mod for the 50 and it adds a lot to the motor. 

[MorganM]

Thanks for the info- it's good to have options and I wouldve been totally bummed if I fit the carb and then discovered the throttle cable was a 'no go'!

 

I've used Pine Sol before(soaked a small carb for 12hrs in 100%PS), but it stripped the carb of it's original smooth finish...for that reason, I probably wouldnt use it again.  At least not on the carb body, I'd use it to soak jets or other brass pieces.

[mjwwf5]

The custom intake from fast50s is $60. Its pricey but I know it will work well.

[Go Big Red]

The custom intake from fast50s is $60. Its pricey but I know it will work well.

I am still learning the hard way in regards to paying up front once to do it right the first time.  Looking back now, I should have picked one of those up for the carb mod.  

[firefighter1868]

This is what mine looked like when I took it out today. Nasty!

[dbart250]

Dammit..now i have to do this! Im

Assuming theres enough interference left to keep it pressed in? Can you get just a pilot if i manage to eff this up?

[firefighter1868]

You can do it. I put vise grips close to the top and not a lot of pressure and gave it a twist and pull and it came right out. Had to work with it awhile before I could open get the wire through the hole. Best advise it get the gallon of carb cleaner and let it soak over night. Back the screws out and count the turns before removing. Blow out all the jets and any hole that go through the carb.

I've had my gallon for three years and use it a lot with all my lawn equipment when they act up.

[dbart250]

Update on me doing this. First off, thank you to the OP for posting. I popped the pilot out and sure enough it was clogged. Filled the bike up with gas today and it started first kick and idled perfectly. Last season you had to blip the throttle to keep idle until it hit operating temp. Thanks again. This technique worked perfect.

[denny49]

I have a stock 2008 CRF50 and I've been battling with a common problem on these things - the pilot jet gets clogged up. You can tell because the bike will usually run OK but just won't idle at all, and it's impossible to adjust it out. I tried all the usual stuff, soaking the carb, compressed air, clean it with wire, spraying with a can of carb cleaner, etc. Even a trick I saw on this forum about heating it up with a lighter. Nothing would work - it seemed like whatever was in there was pretty solid - when I tried using wire, it just stopped cold when I tried to feed it through, just like it was hitting something solid.

I was just about to order a replacement carb when I read a few posts about guys removing the pilot jet, even though it's pressed in. A few people warned that you may completely ruin the carb trying that, but I was already on the verge of replacing the stupid thing anyway, so I figured I'd give it a go.

So, I lightly clamped a set of vise grips to the jet, and gave it a light tap, and I'll be damned if that thing didn't just pop out - easy as that. Here I'm just about to give the vise grips a light tap with the hammer (note the carb is just sitting on the vise, not clamped in):

Here's the jet, just after it came out:

After I got it out, I let it soak in carb cleaner for 30 minutes or so, then got after it with more cleaner, and a small piece of wire. I FINALLY started making some progress with the wire, then soaked it some more, then some compressed air, etc, etc. You've never seen a grown man so happy to see this:

After I worked the wire in and out and was sure it was clean, I put it all back together by lightly tapping it back in:

I put it all together and it runs like a champ - the kiddos rode it all afternoon. So, if you're working this same issue, I hope this is some help. The keys to making this work for me were removing the jet so I could really get to cleaning it, and also using the right kind of wire. Someone in a another thread suggested using a single strand from a brake wire - that's what did it for me. (I actually used a piece from a bicycle shift cable, which is about the same thing) I think all the other wire I tried (electrical wire, mostly) was either too big, or just not strong enough.

Many thanks to the folks who've posted suggestions on this topic here on ThumperTalk - reading through all that was a big help.

I have been using torch tip cleaners for cleaning pilot jets and it works great. Just make sure you don't make the jet bigger by forcing an oversize wire in there.

Denny

[BLACK DEATH]

Very old thread but.....

Well my pilot jet is clogged, so it looks like ill have to pull it out and try running wire through it.

Bad thing is that hole has to be very very small.

I already soaked it in carb cleaner for about an hour.

I also boiled it, but not as long as i should, as this usually cleans anything out.

So bicycle brake line is good to use?