Oil & fuel coming out of air filter

Okay, got the carbs cleaned, new float needle&seat, adjusted the float height originally to 25mm granted the manual says 32mm which there isn't even that much play in the bowl...put it all back together and after 5 minutes fuel was pouring out the left carb over flow. Pulled the carbs again and adjusted both to 27mm, no more overflow but starving for fuel at wot. Used the fuel level technique to see where the level in bowl was and I was reading 13mm from the gasket flange to the level...Where the heck is this level supposed to be at???
 
26-28mm Is the bike falling on it's face at the red line? What air filters are on the bike?
 
open up them carbs again, clean them once more and check out your jet sizes. If a proper cleaning (and clearing all the small passages) doesn't help the second time around, get some bigger jets. Two sizes up on the mains, one on the pilot to start with. Your pods are making the bike run lean, the rpm spiking and dying is typically a lean running issue.
 
have you synced the carbs yet? i had some stumbling issues when revving in the mid range. i rejetted and never synced.
 
Carbs resync, off by an 1/16 turn,

When 1/2 throttle it will rev to redline (bike sitting) and stay steady, WOT is when it falls flat ...the second cleaning did not help anything...Got the floats adjusted fine to...this was a couple weeks ago, I forgot what the main jet sizes were though...
 
With a vacuum carb when you hit the red line that's you wot. When you twist the throttle all the way open it will bog the engine:) If the bike while you ride it will hit the red line it is working correctly. You want to read the tach not your right hand.:wink2:
 
With all due respect to your experience Chris, I have to disagree.

Wide Open Throttle is just that, the throttle butterflies are wide open. This can happen at any engine RPM, or with the engine not running. It is purely mechanical and has no direct action on the slides.

The vacuum that is applied to the slides and diaphragms is what makes the slides lift against the force of the springs and gravity that are trying to keep the slides down. This is done to ensure that the venturi in the carbs is the correct size to provide accurate fuel metering over a broad airflow range. The purpose is to ensure smooth throttle response and performance. But not outright (maximum) performance.

At WOT and high engine RPM (7000 RPM+), the slides should be close to or fully open. At WOT and low RPM, the slides will only lift once there is enough vacuum created to overcome the spring pressure and gravity acting on the slides. This should prevent bogging and offer smooth acceleration throughout the RPM range. It is quite possible to operate the engine at redline and part throttle (lower gears in particular), and in this case the slides will not be fully lifted.

One way to test for correct operation is to be riding the bike in 3rd or 4th gear at 2000 RPM and then rapidly and fully open the throttle. The bike should accelerate smoothly to the redline. If the jetting is correct there should be no bogging, hesitation, etc. Just a smooth pull that gets stronger as the revs increase, up to the HP peak, and then lessening until the redline is achieved. Our bikes don't have a rev limiter, so it is possible to over rev the engine if care is not taken.

Hope this helps...
 
this summer when watching videos on cleaning and rebuilding carbs i found one where a guy took is pods off, hooked a go-pro up facing into the carbs and took a ride to see the slides in action at different speeds.... ill try to find it
 
In terms of tuning "WOT" refers to that state when the slides are all the way up.

More commonly WOT just means the throttle is open all the way.

You're both right :p
 
The only time I have even come close to my right hand turning the grip to "WOT" is pulling a steep hill in too high of a gear. Even running at red line in the first four gears I only have to crack it about 1/2 open:shrug: If he is new to a bike with CV carbs compared to a VM setup it can be a bit confusing. With a perfect running bike cruising at 60mph if you open it quickly to WOT it will bog.
 
so this bike should bog down and not go over 6500 rpm when in any gear???

Could this be a pinhole leak in a diaphragm??

Also it seems to get worse at operating temperature.
 
Flooding = you're too rich.
Bogging = you're too rich.
Performance suffers as engine heats up = probably too rich. (warmer air is less dense and therefore the ratio of fuel to air further favors fuel)

Pinhole in diapragm? Probably not. A true pinhole might not even cause any problem; you're dealing with an elastic material. Every time I have seen one fail it is almost always an obvious tear.

The bike should never bog normally unless you're in 4th, 5th, 6th gear at 10 mph, etc. You should be able to run to redline.

How many sizes up did you go on the mains? Did you verify your float height with an external clear hose?
 
marineviper said:
so this bike should bog down and not go over 6500 rpm when in any gear???

Could this be a pinhole leak in a diaphragm??

Also it seems to get worse at operating temperature.
Click to expand...


Hell no! But if people want to accept that, who are we to argue?

Sounds like a rich mixture, fouled plugs, or ignition breaking down once warm.
 
float height using the hose is 3mm below the flange lip which is where it seems searching the sight that it should be at...

the jets were the factory 142.5 if i remember right.
 
marineviper said:
float height using the hose is 3mm below the flange lip which is where it seems searching the sight that it should be at...

the jets were the factory 142.5 if i remember right.
Click to expand...

You want about 2mm below the flange, but what you have may be ok.

137.5 is stock for mains on my 1978. I think I am running 142.5s myself, but I have pods and 2-1 exhaust.

Someone may have jetted your carbs previously.

All signs are pointing to you being too rich.

Some other quick reading is pointing to your 1980 as having a 135 main jet stock.
 
So on the center stand it will rev to red line. When you ride in any gear it wont go over 6500 rpm's. What year is this bike? Also could you post some pics of it so we can see what setup you have. Are you doing a gradual twist of the throttle or are you dropping it in gear and twisting it all the way open in each gear.
 

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