Author Topic: 2002 B12 Rough Idle  (Read 9682 times)

Offline ant_129

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2002 B12 Rough Idle
« on: July 25, 2014, 05:43:58 PM »
Hello Everyone,



Its been a long long time since I've posted.  Too long.  I guess thats a testament of how solid these bikes are. 

For the past year and a half I've had some idling issues.  I would have to run with choke slightly cracked or my bike would die until it warmed up.  I've adjusted the idling screw plenty.  It was worst in the "winter" (I live in Houston) and not a big issue in summer until recently.  Its gotten worst, so bad it won't hardly idle at all.  It runs fine but as soon as I slow down it dies, nothing I do with the idling screw fixes it. 

Round 1: I change oil, air filter, spark plugs, and ran sea foam through it.  It didn't seem to help.

Round 2: I pull the carbs and clean them up, put them back together.  It now runs worst... Though I may know why.  If you check out this post http://forums.banditalley.net/index.php?topic=13616.msg106819#msg106819 the third picture with the "T" connection.  Mine are completely gone, crumbled away when I pulled the carbs.  I probably need to replace those.  Also I only pulled the top off of one of the carbs that houses the diaphragm and I couldn't get the diaphragm seated back in properly.  It was stretched more than the seat.  I also  notice on another carb that I didn't pull the top off some rubber from the diaphragm sticking out.  I'm sure thats not helping.    Also I did not actually pull the jets and clean in those. 

So my plans include replace the T and hose, buy a carb rebuild kit, pull the jets, clean and replace all the diaphragms.  Does this sound reasonable?  Are all the things I mentioned likely the cause of my idling woes?
02 Bandit 1200S
Holeshot 21" slipon
Holeshot Stage 1 jet kit
Givi engine guards

Offline pmackie

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Re: 2002 B12 Rough Idle
« Reply #1 on: August 03, 2014, 12:20:09 AM »
In a nutshell, yes, it is VERY likely that your idle issue is carb related. Yes, replace any swollen, rotted or broken parts. If you can, have the carb bodies cleaned, or at a minimum, blow all orifices out with compressed air, and make sure they are clean. Pay special attention to the pilot jet circuit. Also make sure you replace any and all O-rings.
Paul
2002-GSF600S, Progressive Fork Springs, B12 Shock,
SS Brake lines, EBC HH pads, Leo Vince Ex & Kappa bags.
Ex Bike Mechanic (late 70's), somewhat rusty
32 years in the Fuel/lubes industry(Retired)

Offline bkm9779

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Re: 2002 B12 Rough Idle
« Reply #2 on: October 26, 2014, 12:11:14 AM »
I had the same problem found the reserve filter popped off all the sediment in the tank stuck my floats open; the bike ran fine but wouldn’t idle at all. Cleaned and installed new needle & seats, but had to adjust the float levels, after market ones were different shut off heights, the plastic float cradles are a pain and it wasn’t easy.