[solidONE]

If it ran correct when cold and got worse its carbs.
Did you ever try and tape over the af, block vome air flow?

What's up with cutting your springs? Is that common sv carb practice?

Actually i did tape the filter opening, and it ran much better.

i don't think the little springs that are in the jet needle holder are realy making much of a difference. I had the original springs in both of them before I lost one of the springs. It actually runs much better than before after I changed the springs. But I think it has more to do with the tape over the air filter than the springs. No this is not common practice. Just trying to make due without having to order parts. I realy doubt they will have this little spring in stock at the local parts shop.

 

[robfromsc]

Depends on the shop, they may, could be a spring that's fits 100 different bikes.
Hmmmm, somethings jacked up. If you were closer to sc I'd tell you to bring it by and we'd figure it out.
The only other things I can think of off the top are,
Diaphram
Spring
Slide sticking
Float level/ stuck float.

Your not gettin enough fuel.

Carbs can be a great thing or they'll make you lose your mind!

 

[solidONE]

Honestly, with my current settings (I still haven't made any adjustments) it runs quite strong for a backfireing engine. Performance is good, beside the lumpy idle. I think I'd better recheck the float height and adjust the idle mixture screws before I put bigger main jets in. I'll check the diaphram and springs for binding while I'm at it. The only real issue right now is idle ~ 1/4 throttle.

 

[solidONE]

Just got done re-re-re-readjusting my carbs.

1. I checked the diaphram, and no problems or damage.

2. Replaced the little needle jet springs with factory ones. No binding.

3. 3 Shims instead of 4

4. 2 1/4 turns on the mixture screw

5. Re-re-re checked all vac hoses and connections for leaks.

I forgot to re-re-re check the float height. :confused4:

I started her up and synced the carbs. After the carb was synced, I tried to adjust the idle with the vaccum gauge still attached. The idle is as lumpy as ever at 1500 rpms, and a bit of light popping at 3000 rpms. Looking at the vaccum gauge, it was apparent that it's the front cylinder that's popping. Vaccum fluctuations from the front carb while popping. Rear carb readings did not fluctuate like the front. I tried to richen up the idle mix in the front cylinder. First by turning the mixture screw out 1/4 turns in the front while idling. No effect... so I turn it out 1/4 turns more for a total of 3 turns out. Still the same. All this was done with the airbox on, just in case you were wondering.

I didn't go for a test ride, but before the new adjustments it was running realy strong aside from the poor idle. Only thing I didn't re-re-re adjust or check this time around was the float hight.

Carbs can be a great thing or they'll make you lose your mind!

:tard: INDEED! :confused4: I'm definatly losing my mind...

Is it possible to check the float height without taking the carbs out again?

 

[SpeedisaVirus]

Hell, just pick up a new set on ebay...

 

[Turd Ferguson]

Is it possible to check the float height without taking the carbs out again?

If you say its running strong except at idle, and at idle its jumping around 1500 rpm, I doubt it's your float. Did you check to make sure theres no cracks or anything in your front carb hoses?

 

[solidONE]

Did you check to make sure theres no cracks or anything in your front carb hoses?

Did he just ask me that...? :confused4: short answer is YES.

 

[solidONE]

Hell, just pick up a new set on ebay...

What..., and take the easy way out??? Let me fiddle with it some more. Plus I just looked on e-bay.... none available yet. If I can find what is malfuctioning in the carb, I'd rather replace the part and fix it... Much more gratification.

 

[robfromsc]

Can u swap carbs with some one near by? Or front carb to the back? Is that possible? Tryn to isolate a carb problem or bike problem.... I know you said the valves are good...but that always pops into my head.... A tight vavle can do that.

But don't by a new carb, fix it, you'll feel better and be able to pass it along!

 

[Turd Ferguson]

Did he just ask me that...? :confused4: short answer is YES.

Im just shootin ideas out there, because all of yours have worked so wonderfully as well.

 

[solidONE]

Im just shootin ideas out there, because all of yours have worked so wonderfully as well.

Dude..... Read my post before your previouse post. Specifically #5 on the list of things I checked.

5. Re-re-re checked all vac hoses and connections for leaks.

Now read your post after that

Did you check to make sure theres no cracks or anything in your front carb hoses?

A tight vavle can do that.

.

How would my valves get tighter if I havent adjusted them? They only get looser with use. It's not like the shims are going to grow any thicker...

I'm going to check the float height again anyways. That's the only thing on the carb I haven't checked for the 5th time. Nothing else left to check.

The current engine I have only has about 11,000 miles on it, so the valves are not likely out of adjustment. I was also hoping to ride her for one more season before I crack the engine open.

I guess I'm going to have to ride around with lumpy or high idle untill I rebuild.

:blob8: CAAAAARRBSAHHHH!!!!! :angry2:

 

[robfromsc]

A valve will become tight. As the vavle opens and closes the seat and the valve "wear", closes the valve to get tight. As the cam lobe comes around it never fully closes and stays slightly open, you lose compression...blah blah blah...
Now that's not the best explanation but its close.
Not all bike will get tight vavles, some will, easy some won't.... Dunno about the sv... My gs does, almost every time I check em. My zrx had 1 , 1 time.
That will cause backfire, stumble, and hard starting.

 

[solidONE]

What you describe as "tight" is what I consider "loose." I'm sure niether terms are "technical," Potayto...Potahto... i guess. I'm thinking maybe the exhaust valves on the front cylinder might be damaged from the backfireing and lean mixure. Definat possibility.

Just got back from a test ride at night. Just as expected, backfireing when I close the throttle past 5000rpms. At least now I know it just the front cylinder. WOT performance was decent. Still pulls hard past 6000rpm, just as it should. The 4th shim I had on it previously definatly helped the lean condition in the front. Has anyone hear of putting 4 shims in front and 3 in the back??? Just don't sound right, does it? With 4 shims the backfiring was minimal. If it was the valves I dont think the extra shim would make that much a difference. I could be wrong tho. As I'm a carb :tard: .

Check out what the lean mixture does to my front pipe...

Looks cool eh...

 

[Turd Ferguson]

The 4th shim I had on it previously definatly helped the lean condition in the front. Has anyone hear of putting 4 shims in front and 3 in the back??? Just don't sound right, does it?

No it doesn't sound right. Shims may help to cover up the problem but I'm pretty sure most people would agree (yourself included) that the shims are not the cause of nor the solution to this problem.

 

[Regular_Joe]

"Where is the earth shattering kaboom?"

 

[andyauger]

Unfortunately, both rich and lean conditions can lead to unusually high exhaust temperatures. It sure sounds more and more like a vacuum leak. Also, you tried to richen the front idle, try leaning it out. Both idle screws should be in as far as possible while providing a smooth idle and smooth off-idle transition. What you are describing at idle could be too much fuel. Think: Does it sort of sound like you've left the choke on too long?

 

[solidONE]

Unfortunately, both rich and lean conditions can lead to unusually high exhaust temperatures. It sure sounds more and more like a vacuum leak. Also, you tried to richen the front idle, try leaning it out. Both idle screws should be in as far as possible while providing a smooth idle and smooth off-idle transition. What you are describing at idle could be too much fuel. Think: Does it sort of sound like you've left the choke on too long?

I'm pretty sure its lean. I have also tried turning the idle screw in further. Idle gets worse. Pulled the pulg and it was a grayish color... lean. Loud pop... lean. Hot exhaust... lean... And yes symptoms does sound like a vaccum leak. But there are none. None I can find at least.

No it does not sound like I have the choke on too long. It does burp and stumble a little at normal idle speeds. It does have stints where everything runs perfect for seconds, then revert back to being lumpy. sigh... :angry7:

 

[robfromsc]

Again, just idea...
Sure there isn't any trash in the carb? A spec in one of the circuits can cause greif! I always clean em and blow em out with compressed air at rebuilds, just watch your eyes!

 

[Regular_Joe]

Can't you spray carb cleaner around to check for a vacuum leak. When it hits the leak it gets sucked in and makes the bike rev up. Did you try that?

 

[solidONE]

Can't you spray carb cleaner around to check for a vacuum leak. When it hits the leak it gets sucked in and makes the bike rev up. Did you try that?

Did that one already. That was one of the first things DonnieJ suggested. I think it was donnie... Anyways, I did do the carb cleaner trick and it did not react.

I've been riding around with the idle like this for a couple of days. The idle seem to get slightly better the more I ride. A couple of times it seemed like it was idling perfectly, but then become lumpy again. Feel's like somebody put a hex on my front carburator. I've checked and tried almost everything besides an exorcism.

I think the problem resides within the front carb's mechanisms. At least, I've isolated the problem to the front carburator. I'm going to disect it once more and clean it out thuroughly. Fingers crossed...