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Re:Choke/carb doesn't work properly
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TOPIC: Re:Choke/carb doesn't work properly
#1022171
BobStar32 (User)
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Re:Choke/carb doesn't work properly 1 Month, 1 Week ago  
Is there any problem to use the existing fuel filter?

And what about no fuel filter?
 
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#1022178
SKWEARpeg (User)
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Re:Choke/carb doesn't work properly 1 Month, 1 Week ago  
BobStar32 wrote:
Is there any problem to use the existing fuel filter?

And what about no fuel filter?


There is a fine screen on the petcock tubes, and some have skipped the filter altogether.
I'd encourage you to remove the small screen filter in the end of the carb inlet.

The factory filter is an obnoxiously ugly piece of plastic that hides behind the chrome cover over the fuel pump.

I like the ff1203, for the simple reason it allows a fat spot in the road for the air to separate from the fuel when the fuel starts to slosh in the tank, and the petcock tube picks up a big gulp of air. Without that wide spot, the air bubble travels all the way to the bowl.
 
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Re:Choke/carb doesn't work properly 1 Month, 1 Week ago  
SKWEARpeg wrote:
BobStar32 wrote:
Is there any problem to use the existing fuel filter?

And what about no fuel filter?


There is a fine screen on the petcock tubes, and some have skipped the filter altogether.
I'd encourage you to remove the small screen filter in the end of the carb inlet.

The factory filter is an obnoxiously ugly piece of plastic that hides behind the chrome cover over the fuel pump.

I like the ff1203, for the simple reason it allows a fat spot in the road for the air to separate from the fuel when the fuel starts to slosh in the tank, and the petcock tube picks up a big gulp of air. Without that wide spot, the air bubble travels all the way to the bowl.


Yeah I know it's not very good looking, this is why I wanted to just ditch it.

Not a bad idea about the fat spot. I'll keep it in mind.
 
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Re:Choke/carb doesn't work properly 3 Weeks, 5 Days ago  
It's done !
My bike is now pumpless.

I checked float level and it's between 2-3mm per manual says.

On startup in the morning it happened many times that bike start well with enricher, but after warmup when I turn throttle just a little bit or more engine stutter and stall. I have to pull enricher full start it up, push it halfway and start to ride before to push it back. I can ride 100-200 km without any problems until I stop it and try to restart it 20-60 minutes after a coffee/beer stop. It doesn't happen all the time, but most.

For now I don't have any filter on my fuel line and I'm straight from petcock to carb passing under intake manifold.

I also feel like engine now run leaner, I checked spark plug and they're more grey than brown. Still have the 165 stock main jet with regular air filter and V&H longshot. And I did not changed any thing but needle valve and o-ring gasket.
 
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#1022942
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Re:Choke/carb doesn't work properly 3 Weeks, 4 Days ago  
It's pretty typical to have the Enricher out about halfway, until the bike warms enough to run without it. Choke systems of old, would incrementally reduce the amount of choke on the airflow, as the motor warmed.
On the bikes, the Enricher provides more fuel and air, instead of choking the air supply. The principle is the same however. The motor needs a richer environment until it gets up to full operating temperature. You as the rider, decides when enough is enough.
Make sure your hot idle is set close to 900rpms.
 
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Re:Choke/carb doesn't work properly 3 Weeks, 4 Days ago  
I totally understand that. But this problem is new since this modification.

Even if choke is pulled halfway and engine is warm, it can happen. I can also roll few meter before. My impression is there is not enough fuel inside the bowl on startup. So when I it the gas there is too much air for fuel supply.

What I don't understand is why only when I start the bike ?
 
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#1022982
SKWEARpeg (User)
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Re:Choke/carb doesn't work properly 3 Weeks, 4 Days ago  
It sounds like you may have an air leak. It may have been part of the problem before. It'd explain the seemingly lean condition now. Since vacuum is at its max when the throttle is closed for starting, it'd be most noticeable then, and right off idle.

I also noticed you mention fuel dripping from a hole in line with the needle. Are you talking about the PMS location? Is it dripping out of there below the carb?
 
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Re:Choke/carb doesn't work properly 3 Weeks, 3 Days ago  
SKWEARpeg wrote:
It sounds like you may have an air leak. It may have been part of the problem before. It'd explain the seemingly lean condition now. Since vacuum is at its max when the throttle is closed for starting, it'd be most noticeable then, and right off idle.

I also noticed you mention fuel dripping from a hole in line with the needle. Are you talking about the PMS location? Is it dripping out of there below the carb?


I was speaking about the hole beside the pilot air jet, in line with the main jet needle on inlet side of the carb. The new needle valve solved that problem.

Today I tried to just open gas cap few second before to start the bike. Maybe it was just coincidence, but it did not happen again yet.
It seems to confirm the impression I have that bowl is not full of gas when I start the bike. I might have to check for routing of my fuel line and also vent hose of gas tank.
 
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Re:Choke/carb doesn't work properly 3 Weeks, 3 Days ago  
BobStar32 wrote:
SKWEARpeg wrote:
It sounds like you may have an air leak. It may have been part of the problem before. It'd explain the seemingly lean condition now. Since vacuum is at its max when the throttle is closed for starting, it'd be most noticeable then, and right off idle.

I also noticed you mention fuel dripping from a hole in line with the needle. Are you talking about the PMS location? Is it dripping out of there below the carb?


I was speaking about the hole beside the pilot air jet, in line with the main jet needle on inlet side of the carb. The new needle valve solved that problem.

Today I tried to just open gas cap few second before to start the bike. Maybe it was just coincidence, but it did not happen again yet.
It seems to confirm the impression I have that bowl is not full of gas when I start the bike. I might have to check for routing of my fuel line and also vent hose of gas tank.


Did you vent the cap per the instructions on the Tech Articles page?

Gravity never sleeps, so if the fuel level in the bowl, when the bike is vertical(not leaning on the side stand)is about 3mm above the bowl to carb mating surface on the manifold side of the carb, starving the bowl with the new grizzly 3.0 needle and seat is not likely to happen. I'd even say impossible. Unless the tank isn't venting properly, and is developing a vacuum as the fuel drains out on its way to the carb.

Keep in mind the possibility of a leak at the manifold to head flange(s). It happens sometimes, where everything is fine but removing and replacing the carb causes just the little whatever. Roadies have a reputation for air leaks there already.
 
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#1023012
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Re:Choke/carb doesn't work properly 3 Weeks, 3 Days ago  
I did not vent the gas cap for now. I was thinking the existing vent on fuel tank would be enough. I might have to do it finally.

For fuel level adjustment, is it supposed to be 3mm over or under mating surface ??

My adjustment is under mating surface as I read in service manual. I know in tech article it say 1-2mm, I figured being 1 more would not be a problem... Maybe Im wrong.

Manifold is brand new with new gasket from begining of summer. Maybe I will have to check for leak.
 
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