2014 Yamaha PW50 Carb - AIr screw?

jpws
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jpws
So, the newer PW50's don't have an air screw on the carb, and instead of a solid brass "plug" (with a tiny hole) in the place of the air screw. it was mentioned that this can be removed and replaced with an airscrew. Anyone know how to remove the plug, and where/how to locate an airscrew here?

The bike literally won't run over half speed with the stock airbox in place. i've drilled a quarter size hole in the top of the stock box to get enough air for it to run - which is dangerous, but works (did it all three motos at Loretta's) and needs to be cleaned each ride.
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racer369
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racer369 8/30/2016 1:47pm
8/30/2016 1:47pm
ILLEGAL mod for LL's bro.
jpws
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jpws 8/30/2016 2:19pm
8/30/2016 2:19pm
racer369 wrote:
ILLEGAL mod for LL's bro.
what is an illegal mod?
drilling a hole in the airbox couldn't possibly me an illegal mod.

and removing the plug to access the airscrew behind it couldn't be a mod either....just adjusting what is there.
racer369
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racer369 8/30/2016 2:24pm
8/30/2016 2:24pm
It is ILLEGAL mod. Pulling plug on carb is not.

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project racer 8/30/2016 6:43pm
8/30/2016 6:43pm
I removed the plug on my TTR50 carb. Use a very small drill bit , drill lightly until you just punch through the plug. Mine came out just by wiggling the drill / bit . They are not in that tight. Don't go crazy on drill speed or depth.

And FWIW, I'm sure he was not the only one bending the rules in the PW class at LL's. It ain't cheatin' till ya git caught...
rrjr
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rrjr 9/1/2016 9:59am
9/1/2016 9:59am
^^^
True that..... 60 kits, QT50 gears, machined flywheel. removing the oil pump gear, plugging the oil line but leaving the tank so it looks like it's connected and running pre-mix. So many ways to make a pw faster.

racer369
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racer369 9/1/2016 10:46am
9/1/2016 10:46am
QT 50 gears are legal.
JB 19
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JB 19 9/6/2016 5:04am
9/6/2016 5:04am
jpws wrote:
So, the newer PW50's don't have an air screw on the carb, and instead of a solid brass "plug" (with a tiny hole) in the place...
So, the newer PW50's don't have an air screw on the carb, and instead of a solid brass "plug" (with a tiny hole) in the place of the air screw. it was mentioned that this can be removed and replaced with an airscrew. Anyone know how to remove the plug, and where/how to locate an airscrew here?

The bike literally won't run over half speed with the stock airbox in place. i've drilled a quarter size hole in the top of the stock box to get enough air for it to run - which is dangerous, but works (did it all three motos at Loretta's) and needs to be cleaned each ride.
I'm surprised that you had a kid that raced LL's and don't know your way around a pw any better than this. There is no need to to drill holes in the air box to make it run right.

PW's are very sensitive to nearly everything. They have to have the carburetor cleaned frequently, (like every other race) 67.5 main jet, air screw adjusted for the weather, very clean air filter with minimal oil, all electrical connections packed with dielectric grease....etc.

Those bikes are almost impossible to completely kill, but getting them to run exactly right and within the rules is a bit of an art. You can make one run clean while using the stock oil injection, but you don't have much margin of error on anything else. Everything has to be CLEAN. Don't forget that running high octane race gas will likely affect jetting and make the bike run richer than normal.

I even run like 20 lbs of air in the tires for less rolling resistance since they handle so well and have very little hp. QT gears are almost necessary.

There are many gray area mods that some people do, but I'd rather not cheat...as well as getting caught cheating and have your kid known as a cheater.
Paw Paw
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Paw Paw 9/6/2016 2:39pm
9/6/2016 2:39pm
racer369 wrote:
ILLEGAL mod for LL's bro.
jpws wrote:
what is an illegal mod? drilling a hole in the airbox couldn't possibly me an illegal mod. and removing the plug to access the airscrew behind...
what is an illegal mod?
drilling a hole in the airbox couldn't possibly me an illegal mod.

and removing the plug to access the airscrew behind it couldn't be a mod either....just adjusting what is there.
Yes that hole is not a legal modification and will lead to a DQ. I have seen many riders get a DQ over items even less than that.

Paw Paw
SCmx
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SCmx 9/9/2016 8:12am
9/9/2016 8:12am
Back to the original question. On the New PW's there is a brass colored plug on the carb where the airscrew normally is. Does anyone know how to remove it?
jpws
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jpws 9/9/2016 1:31pm
9/9/2016 1:31pm
I was told to 1) use a small drill bit to drill gently and shallow into the tiny hole. Once broken through with a "bite", with hand wiggle it and the plug should come out. Or 2) use a wood screw to screw in tiny hole. Once bit, pull out.
Don't drill or screw in too deep. I'd guess the Phillips air screw is 1/8-1/4" behind the gold plug.

1 worked best for me.

I had no idea that a screw was behind it as it appears solid.

jpws
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jpws 9/9/2016 1:46pm
9/9/2016 1:46pm
jpws wrote:
So, the newer PW50's don't have an air screw on the carb, and instead of a solid brass "plug" (with a tiny hole) in the place...
So, the newer PW50's don't have an air screw on the carb, and instead of a solid brass "plug" (with a tiny hole) in the place of the air screw. it was mentioned that this can be removed and replaced with an airscrew. Anyone know how to remove the plug, and where/how to locate an airscrew here?

The bike literally won't run over half speed with the stock airbox in place. i've drilled a quarter size hole in the top of the stock box to get enough air for it to run - which is dangerous, but works (did it all three motos at Loretta's) and needs to be cleaned each ride.
JB 19 wrote:
I'm surprised that you had a kid that raced LL's and don't know your way around a pw any better than this. There is no need...
I'm surprised that you had a kid that raced LL's and don't know your way around a pw any better than this. There is no need to to drill holes in the air box to make it run right.

PW's are very sensitive to nearly everything. They have to have the carburetor cleaned frequently, (like every other race) 67.5 main jet, air screw adjusted for the weather, very clean air filter with minimal oil, all electrical connections packed with dielectric grease....etc.

Those bikes are almost impossible to completely kill, but getting them to run exactly right and within the rules is a bit of an art. You can make one run clean while using the stock oil injection, but you don't have much margin of error on anything else. Everything has to be CLEAN. Don't forget that running high octane race gas will likely affect jetting and make the bike run richer than normal.

I even run like 20 lbs of air in the tires for less rolling resistance since they handle so well and have very little hp. QT gears are almost necessary.

There are many gray area mods that some people do, but I'd rather not cheat...as well as getting caught cheating and have your kid known as a cheater.
And for what's it worth, it Was the 6th time we'd ridden at 2016 at LL. I dont know squat about bikes and , for what's it's worth, without a hold in the airbox it literally wouldn't increase in speed over half throttle .....as if it was on choke. Now that someone graciously shared with me that the plug could be removed I did that - and now with unscrewing about 3 full turns I get the same result as a hole in the top of the box. The rest of the bike is stock as a rock..... And was top 3 in all 3 Moto hole shots.
project racer 9/9/2016 4:30pm
9/9/2016 4:30pm
jpws wrote:
So, the newer PW50's don't have an air screw on the carb, and instead of a solid brass "plug" (with a tiny hole) in the place...
So, the newer PW50's don't have an air screw on the carb, and instead of a solid brass "plug" (with a tiny hole) in the place of the air screw. it was mentioned that this can be removed and replaced with an airscrew. Anyone know how to remove the plug, and where/how to locate an airscrew here?

The bike literally won't run over half speed with the stock airbox in place. i've drilled a quarter size hole in the top of the stock box to get enough air for it to run - which is dangerous, but works (did it all three motos at Loretta's) and needs to be cleaned each ride.
JB 19 wrote:
I'm surprised that you had a kid that raced LL's and don't know your way around a pw any better than this. There is no need...
I'm surprised that you had a kid that raced LL's and don't know your way around a pw any better than this. There is no need to to drill holes in the air box to make it run right.

PW's are very sensitive to nearly everything. They have to have the carburetor cleaned frequently, (like every other race) 67.5 main jet, air screw adjusted for the weather, very clean air filter with minimal oil, all electrical connections packed with dielectric grease....etc.

Those bikes are almost impossible to completely kill, but getting them to run exactly right and within the rules is a bit of an art. You can make one run clean while using the stock oil injection, but you don't have much margin of error on anything else. Everything has to be CLEAN. Don't forget that running high octane race gas will likely affect jetting and make the bike run richer than normal.

I even run like 20 lbs of air in the tires for less rolling resistance since they handle so well and have very little hp. QT gears are almost necessary.

There are many gray area mods that some people do, but I'd rather not cheat...as well as getting caught cheating and have your kid known as a cheater.
jpws wrote:
And for what's it worth, it Was the 6th time we'd ridden at 2016 at LL. I dont know squat about bikes and , for what's...
And for what's it worth, it Was the 6th time we'd ridden at 2016 at LL. I dont know squat about bikes and , for what's it's worth, without a hold in the airbox it literally wouldn't increase in speed over half throttle .....as if it was on choke. Now that someone graciously shared with me that the plug could be removed I did that - and now with unscrewing about 3 full turns I get the same result as a hole in the top of the box. The rest of the bike is stock as a rock..... And was top 3 in all 3 Moto hole shots.
If you are three turns out on the air screw, you may want to try the next size smaller pilot jet.

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