Ok, I FINALLY think I have one of my carb issues solved. I replaced the float and valve on the #1 carb (far left) and left the tank valve "on" for the last two days. Fired right up last night without a problem.

Now I'm trying to figure out how to adjust the air/fuel mixture screws and what would be the best starting point. When I cleaned the carbs, I put everything back to the point they were, but they either aren't getting enough fuel or something because the bike will idle fine at 1500 then just sputter and die. To restart I need to roll slightly on the throttle while using the starter button. After a while I think I flooded a few cylinders that way because then it would start, but run at 2k and not go any more.

When I cleaned the carbs I never touched the butterfly openings on three, but in looking at the first carb, I noticed i couldn't see any light compared to the other three, so I opened it ever so slightly.

Anyway, with regards to the mixture screws, some were originally set at 1 3/4 turns, some more. Should I just set them all to 2 or 2.5 and see what it does? i'm assuming these let more fuel in at idle the further out they are turned?

thanks guys.

 

I highly suggest downloading the service manual and balance the carbs!!!!!!!! The service manual clearly outlines how to adjust the carbs ( page 55 section 6-14)

If you don't have California model OR Canadian and don't live above 6,500 ft, then the manual states:
1. Turn each pilot screw clockwise until it seats LIGHTLY, then back out the screws to 2-1/8 turns

2. Warm up the engine to operating temp (10 min)

3. Attach a Tach (built-in tach isn't accurate enough)

4. Adjust idle speed (**** on side of bike) to 1200 RMP + or - 100 RPMs

5. Turn all pilot screws 1/2 turn counterclockwise from initial setting

6. If engine speed increases by 50 RMP or more, turn all screws out in 1/2 turn increments until the engines speed doesn't increase.

7. AGAIN Adjust idle speed (**** on side of bike) to 1200 RMP + or - 100 RPMs

8. Turn number 3 carb pilot screw IN until engine speed drops 50 RPM

9. Turn number 3 carb pilot screw counter clockwise from that point.

10. AGAIN Adjust idle speed (**** on side of bike) to 1200 RMP + or - 100 RPMs

11. Perform the steps 8, 9, 10 for carbs 1, 2 and 4.

That is nearly verbatim of what is in the service manual.

 

Yeah, thanks I do have the manual. Just trying to gain some experience from what others have encountered.

I went back last night and set all screws at about 2 1/8 out and started the bike. Ran fine but idle seemed to be a bit off again. Adjusted about another 1/4 turn out from there and now the bike idles at 1600rpms and doesn't skip a beat.

though when I give it gas and holtd the throttle at between 3 and 4k, I detect some slight popping from the pipe and the engine seems rough. I think maybe one of my plugs is screwed up, so I got more to install in the next few days. Local dealer says $120 to go through and adjust all the carbs and for that price, I'm about to schedule the appointment.

 

Well, you are just aimlessly adjusting the carbs. That's not going to yield optimum results. If you don't have a tach accurate down to 50 RPMs then you're basically stuck.

I used this for my tach.
Amazon.com: Actron CP7677 Automotive TroubleShooter - Digital Multimeter and Engine Analyzer: Automotive

but at $40, you are close to the $120. It's up to you whether you want to learn to do it yourself through trial and error (and end up with a new Multimeter) or have someone else do it for the $120. Really depends on you.

 

if your carbs are in good clean/working order and ther sync is good and your motors integreaty is not to be a question meaning valves are in adjustment,timing is right,comp is good then i would start at 2 1/8 out.. if it is poping under load then the fist thing you should check is the plugs like you said... a missing lung could be putting you in the wrong direction..

 

I honestly do not know about the sync. I haven't ever touched anything so I may try and build my own setup to get that done. Wish I could find the tutorial on how to build one and use it.

I originally set everything about 2 1/8 out but under load when at a stop the bike sputtered and hesitated like it was getting way too much fuel. It would also pop some under deceleration. Ran perfect at mid and full throttle, so I'm sure its the low speed circuit. I re-adjusted everything to 2 turns out and it runs much better under load, but still pops some under deceleration. I need to figure out if turning them in increased the fuel ratio, or decreases it. (ie less fuel or more fuel in by turning the screws in.)

The original setup was 1.5 out, 2 our, 2 out, and 1.75 out. Will probably post in general tech about the mixture screws as I need to get it a little better before I jump on the highway and take my bike to the ealer I am having do the final adjustment.

 

im using this link to make my homemade manograph this week is more complicated than it sounds https://cbrforum.com/forum/f2-tech-9...c-tool-114927/ you also need to order vaccum boosts adapters for vaccum ports on your heads and caps if they're not already on the bike (they might be though). The problem I have right now is after I take the carb plastic hosing off theres three open connections that aren't connected woo545 told me not to worry about them, but there's also a missing hose for the air filter thats not connected idk if i should just leave it since normally these are connected when the engines running?

When you adjusted your pilot screws do you have the d shaped tool for it or did you use a dremel to cut a slot in it. also do you have the carbs on when you adjust as well as the engine running?

 

I cut slots with a dremel and I use a screwdriver bit from one of those 4 in one screwdrivers. The bit is long enough for me to hold on to and short enough and small enough for me to reach in and adjust the screws from the side with use of a flashlight.

I do not adjust with the engine running as that would burn. I set them all the same, ran it warm, then let it cool before adjusting again.

Regarding the three hoses, I only know of two. one on the passenger side and one just above where the fuel line goes in. The only other hose I know of is the vacuum hose that goes from the left cylinder to the fuel tank.

I found out when I left for lunch and my bike stalled that I have a fuel tank/petcock issue. The carbs are completely clean, yet I was driving and the bike sputtered and eventually stalled. I pull over, open the fuel cap, close it and start the bike on choke. Runs fine for a bit then I have to do it all over. I'm thinking that the vacuum line (new, btw) either isn't providing enough vacuum, or the petcock is bad and needs work. Since the bike runs great when it has fuel, I'm guessing something is wrong with the petcock.

 

these are the lines i was talking about idk what they are or what they're for also what do you mean by passenger side?

 

The 2 smaller hoses on the side are vent or overflow hoses. They don't hook up to anything else...so leaving them off for the adjustments is fine. The middle hose...I don't remember hooking that up to anything on my bike...could be wrong. However I did leave all of that open when I did the sync/idle adjustments on my bike and it runs just fine. Since you are supposed to remove the airbox to do the sync, I say don't fret over it. Leave it off and do the sync. Besides, you are only adjusting the carbs to makes sure they have equal vacuum pressure.