650 Carb problems, I'm at a loss - Star Motorcycle Forums: Star Raider, V-Max, V-Star, Road-Star Forum
 2Likes
  • 2 Post By pauli466
  • 2 Post By pauli466
 
LinkBack Thread Tools Display Modes
post #1 of 9 (permalink) Old 02-08-2016, 09:52 AM Thread Starter
Member
 
Creeper's Avatar
 
Join Date: Mar 2013
Location: Texas
Posts: 98
650 Carb problems, I'm at a loss

I have an '04 650 that's been parked for two years, now it's having idling problems. Here's the rundown; I drained the gas, pulled the carbs and thoroughly cleaned them, cleaned pilot jets (numerous times through this process), scrubbed every piece, looked through every manual and website I can find. Still don't think I've fixed it properly.

Before I parked it, I installed a Baron's Big Air Kit. Followed instructions, installed 130 main jets, 22.5 pilot jets, new needles with clip in 4th slot, mixture screws 3.5 turns out. Everything precisely per instructions. But, I never rode it to get it set properly. Now after sitting, I went to start it, and couldn't get it to idle without choke. Yesterday, I pulled the needles and moved the clip to the 6th space, then messed with mixture screws until it idled good, and until popping disappeared, as per Mikuni website. Now the screws are 7.5 (front) and 8 turns (rear) out. Since I see everyone else is fine at 3.5 turns, I can't help but think that something else is screwed up, and the mixture screws are simply compensating for it. But at least now it runs without the choke. After a short test ride, I hit the brakes, and it stalls out. (since it's not registered anymore, all I can do is end of street and back, but up to 30 mph) When I went to park it, lean it over on the kickstand, and it stalls. I believe that shows a float level problem, but I'm 100% positive I didn't alter the floats or the little tab that connects to the needle in any way.

What the heck is goin on!?!?!?!?!

One other point, I noticed a vacuum hose that ran from the carbs to near the rear of the air cleaner. For some reason I can't find this hose adressed anywhere, but I plugged it, and made it run better, so I left it plugged. AIS has been removed.
Creeper is offline  
Sponsored Links
Advertisement
 
post #2 of 9 (permalink) Old 02-08-2016, 12:10 PM Thread Starter
Member
 
Creeper's Avatar
 
Join Date: Mar 2013
Location: Texas
Posts: 98
Update, figured out the hose I plugged is the carb vent hose, so I unplugged it. Doesn't want to start at all this morning. Wants to fire when you crank it, but if I give even a little throttle, kills any sound of firing, just cranks.
Creeper is offline  
post #3 of 9 (permalink) Old 02-08-2016, 04:42 PM
Senior Member
 
pauli466's Avatar
 
Join Date: Feb 2015
Posts: 1,309
Garage
Quote:
Originally Posted by Creeper View Post
Update, figured out the hose I plugged is the carb vent hose, so I unplugged it. Doesn't want to start at all this morning. Wants to fire when you crank it, but if I give even a little throttle, kills any sound of firing, just cranks.
check the bowl levels with a piece of clear tubing then go from there. doing that will at least tell you the pump is working and carbs are full.
Creeper and Creeper like this.

dumb bikers don't get to be old bikers
pauli466 is offline  
Sponsored Links
Advertisement
 
post #4 of 9 (permalink) Old 02-10-2016, 10:50 AM Thread Starter
Member
 
Creeper's Avatar
 
Join Date: Mar 2013
Location: Texas
Posts: 98
Thanks Paul.

Just another update; on a whim I went out and started it again last night. Fired up instantly (with the choke on). Then I took a piece of duct tape and with the air filter off, I covered about 3/4 of the air filter joint. Ran like a champ. I noticed before what I believed was some superficial surface cracking on the joints between carbs and cylinders. Pretty sure they're much more than superficial now. So, I'm gonna start by replacing those joints, clamps and o-rings, as well as the upper joints to the air box. I'll check back later and update that. I will also double check the float levels, though I believe what was happening was I was just dumping so much fuel into the heads that the carbs, even set properly simply couldn't keep up.


Also, anyone have a line on some better vaccuum caps for the joints? these have only been on there for a couple months and one is already cracked. And, the bike wasn't even running.


PS, don't ever walk in the house pissed and forget to turn off the key. Word is that will kill the rest of the night for ya. Or so I've heard.

Last edited by Creeper; 02-10-2016 at 10:54 AM.
Creeper is offline  
post #5 of 9 (permalink) Old 02-10-2016, 06:20 PM
Senior Member
 
pauli466's Avatar
 
Join Date: Feb 2015
Posts: 1,309
Garage
when all the ducts and intake boots are tight with no leaks anywhere in the system the air box is pretty noisy especially at low speed in 5th at least mine is. so i'm insulating the silencer box inside and out with 1/8 rubber soundproofing material, i'll let everyone know how it worked in the spring. as far as a vacuum cap go's a short piece of hose with a nice short stainless carriage bolt threaded in always worked for me.

dumb bikers don't get to be old bikers

Last edited by pauli466; 02-10-2016 at 06:25 PM.
pauli466 is offline  
post #6 of 9 (permalink) Old 03-13-2016, 09:40 AM Thread Starter
Member
 
Creeper's Avatar
 
Join Date: Mar 2013
Location: Texas
Posts: 98
Well I got it figured out. Along with the vacuum leaks, the throttle position sensor also tested bad. So after replacing that, and the joints, returning the needles to the 4th slot, and the PMS screws to 3 1/2 turns, she runs great. A wee bit of tuning and sync'd the carbs, she settled at 3 1/8 turns front, 3 1/4 rear.

So, lessons learned, vacuum leaks will cause all kinds of fits, and a 90 degree screw driver is essential for adjusting the mixture screws, unless you want to spend $50 on the after-market finger adjustable screws. You DO NOT want to strip the head of one, and have to use a screw extractor to get it out. Incidentally, the thread chaser size is M6 x .5, (extra fine) and a real mutha to find.
Creeper is offline  
post #7 of 9 (permalink) Old 03-13-2016, 10:20 AM
Senior Member
 
pauli466's Avatar
 
Join Date: Feb 2015
Posts: 1,309
Garage
Quote:
Originally Posted by Creeper View Post
Well I got it figured out. Along with the vacuum leaks, the throttle position sensor also tested bad. So after replacing that, and the joints, returning the needles to the 4th slot, and the PMS screws to 3 1/2 turns, she runs great. A wee bit of tuning and sync'd the carbs, she settled at 3 1/8 turns front, 3 1/4 rear.

So, lessons learned, vacuum leaks will cause all kinds of fits, and a 90 degree screw driver is essential for adjusting the mixture screws, unless you want to spend $50 on the after-market finger adjustable screws. You DO NOT want to strip the head of one, and have to use a screw extractor to get it out. Incidentally, the thread chaser size is M6 x .5, (extra fine) and a real mutha to find.
i'v sprayed plasti dip on the outside of carb joints to seal micro cracks and it works and holds up very well.
Creeper and Creeper like this.

dumb bikers don't get to be old bikers
pauli466 is offline  
post #8 of 9 (permalink) Old 03-13-2016, 11:47 AM Thread Starter
Member
 
Creeper's Avatar
 
Join Date: Mar 2013
Location: Texas
Posts: 98
Never thought about that. They're just rubber anyway. But, since I'm sellin this one, I wanted to do it right. Hate having someone else inheriting my problems.
Creeper is offline  
post #9 of 9 (permalink) Old 03-13-2016, 08:22 PM
Senior Member
 
pauli466's Avatar
 
Join Date: Feb 2015
Posts: 1,309
Garage
Quote:
Originally Posted by Creeper View Post
Never thought about that. They're just rubber anyway. But, since I'm sellin this one, I wanted to do it right. Hate having someone else inheriting my problems.
now that's the right attitude

dumb bikers don't get to be old bikers
pauli466 is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Star Motorcycle Forums: Star Raider, V-Max, V-Star, Road-Star Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome