Carb problems continued

[MSGU1-4936]

At my wits end with my carb problems. I had them off the bike 4 times now. I went back to stock everything except the slip-ons. Idle is poor, seems like I have to have the screws out +3 for any decent idle or power, even that is a joke, cant get over 4-5000rpm, hesitation, backfire from the exhaust.. Placed new plugs in, one looks like its brand new, the other 3 look like too rich. Everything is clean new parts from the carb kit, not sure what to do at this point. If I bring it to a shop out here I'm looking at over $500. Bike was working fine prior except the boots were finished, I replaced those, and noticed the crap coming out from the drain screw so I opened the back of the carb and replaced the parts in there as well as the gaskets etc. I start at 2.5 turns out but its way too lean. I tried the pea shooter, but like I said everything was cleaned when I opened the carbs. Compression is running at 175, 179,180, 183. For an 88 its pretty good.

Floats are correct, I used the upside down method as indicated in ths section, converted from inches to mm

Can anyone tell me what the proper procedure is when I place the carbs back on in order of sequence, maybe I'm missing something. I sync the carbs evertyime, do they need to be synced after every adjustment to the air/fuel mixture screws?

How do you bench sync carbs




Any Suggestions

Ron:bang head:

 

[shawn kloker]

At my wits end with my carb problems. I had them off the bike 4 times now. I went back to stock everything except the slip-ons. Idle is poor, seems like I have to have the screws out +3 for any decent idle or power, even that is a joke, cant get over 4-5000rpm, hesitation, backfire from the exhaust.. Placed new plugs in, one looks like its brand new, the other 3 look like too rich. Everything is clean new parts from the carb kit, not sure what to do at this point. If I bring it to a shop out here I'm looking at over $500. Bike was working fine prior except the boots were finished, I replaced those, and noticed the crap coming out from the drain screw so I opened the back of the carb and replaced the parts in there as well as the gaskets etc. I start at 2.5 turns out but its way too lean. I tried the pea shooter, but like I said everything was cleaned when I opened the carbs. Compression is running at 175, 179,180, 183. For an 88 its pretty good.

Floats are correct, I used the upside down method as indicated in ths section, converted from inches to mm

Can anyone tell me what the proper procedure is when I place the carbs back on in order of sequence, maybe I'm missing something. I sync the carbs evertyime, do they need to be synced after every adjustment to the air/fuel mixture screws?

How do you bench sync carbs




Any Suggestions

Ron:bang head:

Sounds like it is only running on 3 cylinders.

 

[MSGU1-4936]

Sounds like it is only running on 3 cylinders.

Thanks Shawn, but I went to see if that was the case, I removed the spark plug and wire and I have good spark. I then started the bike and felt the cylinder wall and it heated up as quikly as the rest . Not sure and correct me if I'm wrong would that cylinder not be as hot as the others after idling for a few minutes. Is it possible that there is enough fuel to idle but not enough once I place a load on the engine. Is there a way to verify the fuel flow from thr carb to the cylinder. Maybe there is something cloged in the jet, I think I mighj pull the carbs apart and check. If anything I getting pretty good at taking them apart, guess I need more practice at putting them together.

Ron:hmmm:

 

[maleko89]

What are your float levels? Sounds like you pilot fuel jet may be plugged.

Mark
#1098

 

[MSGU1-4936]

What are your float levels? Sounds like you pilot fuel jet may be plugged.

Mark
#1098

Hey Mark, I took your imperial measurement in one of the threads and converted to metric, only had a metric ruler which converted to 28mm, when checking the float uoside down, cut a piece of cardboard 28mm and slid under the float. As well when I emptied the float an equal amount of fuel came out of each carb.

question do you have to sync the carbs after every adjustment with the air/fuel mixture screws, you make mention of bench syncing the carbs can you explain

Thanks,

Ron:cheers:

 

[shawn kloker]

Hey Mark, I took your imperial measurement in one of the threads and converted to metric, only had a metric ruler which converted to 28mm, when checking the float uoside down, cut a piece of cardboard 28mm and slid under the float. As well when I emptied the float an equal amount of fuel came out of each carb.

question do you have to sync the carbs after every adjustment with the air/fuel mixture screws, you make mention of bench syncing the carbs can you explain

Thanks,

Ron:cheers:

As a rule the carbs mostly need synced after having them off the bike not after adjusting the A/F screws.And after running a month or so on the street.They seem to move easily.Flooring it too hard can even knock them out.I sync mine often.Keihin flatslides are a pain in the ass to sync but very nice to change jets.

 

[maleko89]

I wouldn't bother with bench sync'ing. I tried with the last couple of sets I worked on and they were still off quite a bit.

Mark
#1098

 

[one2dmax]

I wouldn't bother with bench sync'ing. I tried with the last couple of sets I worked on and they were still off quite a bit.

Mark
#1098

That's because every cylinder has a different level of suction. You can have them all nearly perfect as far as throttle blade opening but it won't meant that every cylinder has the same suction or draw of fuel.

Sean Morley

 

[MSGU1-4936]

Well I took the carbs apart again and found 3 possible problems,

1. the nut on the enricher mech was loose on the one carb that was running very lean
2. The screw on the post that houses the needle located in the float bowl was loose, same carb
3. I found small particals of left over gasket in the same float bow, when I took the gasket off to replace some was still stuck to the metal, guess I should have cleaned it off properly.

lets hope this is the problem

Ronl