Cleaning clogged idle jets

User avatar
NobleHops
ICOA Member
ICOA Member
Posts: 3867
Joined: Mon Jan 25, 2010 7:17 am
Location: Tucson, Arizona, USA
Location: Tucson, Arizona, USA

Re: Cleaning clogged idle jets

Post by NobleHops »

What Dave said Bill. We're in Tucson, and if we can help in any way, please sing out.
Nils Menten
Tucson, Arizona, USA '80 CBX, sort-of restored :-)

User avatar
BillB
ICOA Member
ICOA Member
Posts: 48
Joined: Sat Apr 19, 2003 9:02 pm
Location: Buckeye, Arizona, USA

Re: Cleaning clogged idle jets

Post by BillB »

Dave and Nils, I appreciate the advice. Makes perfect sense, and I do plan to go through the carbs on both bikes. I did manage to wire out the idle jet in #6 and now that cylinder's exhaust pipe shows good heat on idle. I thought that was all for that bike, the 79, but now cyl 4 shows low exhaust temps on idle. The idle is lumpy and slow and will die unless I raise the idle adjustment screw. The bike runs perfectly off idle. I have a club ride this Thursday I want to go on, and the bike now runs well enough for that. Also, I dumped a bottle of Redline fuel system cleaner in. I will go through the carbs on both bikes soon. I received Mike's book today and reviewed it.

One thing that puzzles me is the orientation of the slides. They are not indexed and neither Mike's book nor the shop manuals mention anything. There is a cutout on one side and I lined that up with a cutout in the bore.

Also, the bikes only sat for 3 months at most. I was surprised I had this problem in Arizona after so many years of no trouble in California. I guess at the very least I need to put in some Sta-bil.

And Nils, I see Mike appears to be in Prescott, about 100 miles north of me. I've known of Mike for almost 30 years and talked to him a few times by phone. I'd be interested in trying to pull together an AZ CBX rally. What do you think?
Bill
79, 81 & 82 CBXs
Others in the garage: 91 Ducati 917ie, 04 RC51, 05 MV Agusta F4 1000, 09 ST1300
ICOA 2924
Buckeye, AZ

User avatar
NobleHops
ICOA Member
ICOA Member
Posts: 3867
Joined: Mon Jan 25, 2010 7:17 am
Location: Tucson, Arizona, USA
Location: Tucson, Arizona, USA

Re: Cleaning clogged idle jets

Post by NobleHops »

I’d come ride with you for sure. Sounds fun!
Nils Menten
Tucson, Arizona, USA '80 CBX, sort-of restored :-)

User avatar
BillB
ICOA Member
ICOA Member
Posts: 48
Joined: Sat Apr 19, 2003 9:02 pm
Location: Buckeye, Arizona, USA

Re: Cleaning clogged idle jets

Post by BillB »

OK, we'll shoot for something this winter...as soon as I rebuild my carbs. I'll get a bead on who is in the state and see what might work.
Bill
79, 81 & 82 CBXs
Others in the garage: 91 Ducati 917ie, 04 RC51, 05 MV Agusta F4 1000, 09 ST1300
ICOA 2924
Buckeye, AZ

daves79x
ICOA Technical Director
ICOA Technical Director
Posts: 4738
Joined: Sun Oct 01, 2006 8:05 am
Location: Knox, PA
Location: Knox, PA

Re: Cleaning clogged idle jets

Post by daves79x »

Bill:

Do not underestimate the value of draining the carbs. Sounds like you've never done it, but especially after you go to the trouble to rebuild them, please do. Forget the stabilizer, just keep the tank full and the carbs drained for any long-term storage.

The slides ARE indexed. They will only go in one way.

Dave

steve murdoch icoa #5322
ICOA Member
ICOA Member
Posts: 4069
Joined: Tue Mar 04, 2003 9:12 am
Location: St. Catharines, On. Canada
Location: St. Catharines, On. Canada

Re: Cleaning clogged idle jets

Post by steve murdoch icoa #5322 »

I know it is not necessary but i also like to keep the same slide with the same carb body.
Had a set once where #5 and #6 would hang up slightly if in the other bore.
Yes, there was a bit of scoring on the slides.

User avatar
BillB
ICOA Member
ICOA Member
Posts: 48
Joined: Sat Apr 19, 2003 9:02 pm
Location: Buckeye, Arizona, USA

Re: Cleaning clogged idle jets

Post by BillB »

Yes, I will keep the slides with their respective bodies. I think Mike makes that comment in his book.

Also, by draining the carbs, I assume you mean running it with the petcock closed until it dies as all the bowl drain screws would be a pain/impossible to get to.
Bill
79, 81 & 82 CBXs
Others in the garage: 91 Ducati 917ie, 04 RC51, 05 MV Agusta F4 1000, 09 ST1300
ICOA 2924
Buckeye, AZ

Larry Zimmer
ICOA Web Post/Pix/Video Archive Mgt
ICOA Web Post/Pix/Video Archive Mgt
Posts: 2196
Joined: Mon Dec 15, 2003 2:32 pm
Location: Brighton, MI
Location: Brighton, Mich
Contact:

Re: Cleaning clogged idle jets

Post by Larry Zimmer »

The carbs each have a drain screw. Open that and let the fuel run out until it is no longer dripping. Open them all together. (Don't forget to close the petcock first. Use the drain stuff in the lawn mower.) Just running the engine until it dies will still leave some in the bottom of the bowls. Only takes 10 minutes to drain carbs. I do it any time the bike is going to sit more than 3 days. Doing this, I have not had to clean carbs the past 25 years. And, the bike sits in storage through Michigan Winters. Starts and runs fine every Spring. [Put a couple shots of Techron into the tank when coming out of storage.]
Larry Zimmer
cbxlarry@sbcglobal.net

AshishNJ
Power Poster
Power Poster
Posts: 375
Joined: Mon Mar 25, 2019 10:26 am
Location: NJ USA
Location: NJ USA

Re: Cleaning clogged idle jets

Post by AshishNJ »

Larry

Do you keep the tank full of gas in winter and add any additives like staybill?
1979 CBX (faster Red)
1981 CBX Streetfighter
2017 Aprilia Tuono.
Past rides : FZ1, BMWS100rr,S1000r,k1300S,YAMA RD350,Enfield 350

User avatar
Jeff Bennetts
Posting God
Posting God
Posts: 2408
Joined: Wed Mar 05, 2003 8:38 am
Location: Ohio, USA
Location: Ohio, USA

Re: Cleaning clogged idle jets

Post by Jeff Bennetts »

Larry Zimmer wrote:The carbs each have a drain screw. Open that and let the fuel run out until it is no longer dripping. Open them all together. (Don't forget to close the petcock first. Use the drain stuff in the lawn mower.) Just running the engine until it dies will still leave some in the bottom of the bowls. Only takes 10 minutes to drain carbs. I do it any time the bike is going to sit more than 3 days. Doing this, I have not had to clean carbs the past 25 years. And, the bike sits in storage through Michigan Winters. Starts and runs fine every Spring. [Put a couple shots of Techron into the tank when coming out of storage.]
When I see an 82 CBX anywhere, anytime, I check to see if it's Larry, most the time it is, why because he knows how to keep that old girl going!

User avatar
BillB
ICOA Member
ICOA Member
Posts: 48
Joined: Sat Apr 19, 2003 9:02 pm
Location: Buckeye, Arizona, USA

Re: Cleaning clogged idle jets

Post by BillB »

OK, I guess the drain screw aren't so hard to get to. I went on a 170 mile ride yesterday after putting a bottle of Redline fuel system treatment in the tank. Did absolutely nothing to improve the idle. Off idle, the bike ran great. So, I need to schedule taking the carbs off. I've got a 4-40 bottoming tap and screw. Heat gun ready. Randaak kits. Mike's book. Carb boots ordered. Might just get some Sirius slow jets too. Thanks for all the advice.
Bill
79, 81 & 82 CBXs
Others in the garage: 91 Ducati 917ie, 04 RC51, 05 MV Agusta F4 1000, 09 ST1300
ICOA 2924
Buckeye, AZ

AshishNJ
Power Poster
Power Poster
Posts: 375
Joined: Mon Mar 25, 2019 10:26 am
Location: NJ USA
Location: NJ USA

Re: Cleaning clogged idle jets

Post by AshishNJ »

Do I have to tap the jets or can I just use certain screw and pull them as Mike’s book shows ?
1979 CBX (faster Red)
1981 CBX Streetfighter
2017 Aprilia Tuono.
Past rides : FZ1, BMWS100rr,S1000r,k1300S,YAMA RD350,Enfield 350

Larry Zimmer
ICOA Web Post/Pix/Video Archive Mgt
ICOA Web Post/Pix/Video Archive Mgt
Posts: 2196
Joined: Mon Dec 15, 2003 2:32 pm
Location: Brighton, MI
Location: Brighton, Mich
Contact:

Re: Cleaning clogged idle jets

Post by Larry Zimmer »

AshishNJ wrote:Larry

Do you keep the tank full of gas in winter and add any additives like staybill?
Somewhat contrarily, I do not. Often it sits half full. What I do is add 3X the amount of Stabil that it says on the bottle. That usually means 3 ounces. Might be overkill. However, same thing on my old Suzuki. Usually 1/2 tank, too. Probably just too lazy to go fill the tank. But, then, it's worked for me here in Michigan. Bikes do sit covered in a garage.
Larry Zimmer
cbxlarry@sbcglobal.net

AshishNJ
Power Poster
Power Poster
Posts: 375
Joined: Mon Mar 25, 2019 10:26 am
Location: NJ USA
Location: NJ USA

Re: Cleaning clogged idle jets

Post by AshishNJ »

Thanks Larry. On the topic question. Once the slow jets are pulled out and thoroughly cleaned, what is the procedure to fit them back? Do they have to be pressed down or to be tapped with some stick and hammer ?
1979 CBX (faster Red)
1981 CBX Streetfighter
2017 Aprilia Tuono.
Past rides : FZ1, BMWS100rr,S1000r,k1300S,YAMA RD350,Enfield 350

User avatar
Gearheadgregg
ICOA Member
ICOA Member
Posts: 366
Joined: Tue Sep 30, 2014 9:47 am
Location: Rhode Island
Location: Rhode Island

Re: Cleaning clogged idle jets

Post by Gearheadgregg »

IMG_2999.JPG
AshishNJ wrote:Do I have to tap the jets or can I just use certain screw and pull them as Mike’s book shows ?
Just carefully screw into the slow jet about 3 turns and pull them out , i never had to run a tap first unless they are corroded bad . Just a light tap to reinstall does not take much
You do not have the required permissions to view the files attached to this post.

Post Reply

Return to “CARBS: Cleaning, Rebuilding, Swaps, Aftermarket, Tuning, Syncing, and More”