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Will it hurt to increase air flow?


Discussion at Motorized Bicycle Engine Kit Forum in the Motorized Bicycle General Discussion forum. I have read that the standard black plastic air breather is restricting the motors air flow and thus some performance. ...
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Old 08-08-2008, 12:02 AM
saetta's Avatar
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Default Will it hurt to increase air flow?

I have read that the standard black plastic air breather is restricting the motors air flow and thus some performance. I have seen these two stroke bike motors with another kind of breather with full access screen opening.
Will it run too lean or will it just pick up more fuel with the increase in air flow?
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Old 08-08-2008, 01:09 AM
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Default Re: Will it hurt to increase air flow?

No it will not hurt but it might cause you to run a little lean and you might have to change the clip on the carb.

Bicycle Engine Air Filter

Last edited by fairracing31 : 08-08-2008 at 01:40 AM.
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Old 08-08-2008, 07:48 AM
Master Motorized Bicycle Builder
 
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Default Re: Will it hurt to increase air flow?

I have a filter that lets in more air I lowered the clip to make the mixter richer I checked ny plug so far it looks good.

My bottom end and top end are better, but I also have a shorter intake.
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will-hurt-increase-air-flow-new-carb.jpg  will-hurt-increase-air-flow-short-intake.jpg  
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Old 08-08-2008, 08:10 AM
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Default Re: Will it hurt to increase air flow?

Thanks. Exactly what clip are you talking about?
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Old 08-08-2008, 08:14 AM
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Default Re: Will it hurt to increase air flow?

There is a clip on the needle in the carb...moving it up makes the engine leaner, moving down obviously make it richer. It's the only adjustment on the carb other than the idle speed.

More air need more fuel, Less needs less.
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Old 08-08-2008, 09:48 AM
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Default Re: Will it hurt to increase air flow?

Quote:
Originally Posted by MarcPhotoMan View Post
I have a filter that lets in more air I lowered the clip to make the mixter richer I checked ny plug so far it looks good.

My bottom end and top end are better, but I also have a shorter intake.
If a 2-stroke is anything like a car motor, I'm not surprised your top end is better. But I figured the bottom end would suffer a bit. Shorter intake = more high rpm hp but less low rpm tq. Longer intake = more low rpm tq, but less high rpm hp. For cars anyway. These darn 2-strokes are still new to me. I guess maybe the air filter alone helped your bottom end, and the shorter intake runner helped the top end.
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Old 08-08-2008, 12:51 PM
Master Motorized Bicycle Builder
 
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Default Re: Will it hurt to increase air flow?

I geuss that's what happened! I am pleased with it , my only problem is that it has been rainning for days here!

I am not willing to ride in the rain and damage all that work i did!
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Old 08-08-2008, 04:22 PM
Master Motorized Bicycle Builder
 
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Default Re: Will it hurt to increase air flow?

[quote=MarcPhotoMan;26135]I have a filter that lets in more air I lowered the clip to make the mixter richer I checked ny plug so far it looks good.

I like the Air Cleaner Where did you find it at my stock one is too large for my frame.

Greg
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Old 08-08-2008, 09:32 PM
Master Motorized Bicycle Builder
 
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Default Re: Will it hurt to increase air flow?

Quote:
Originally Posted by Tj Bunch View Post

I like the Air Cleaner Where did you find it at my stock one is too large for my frame.

Greg
I purchased a new carb from live fast motors, but it really really about the same size as the stock carb
Livefast Motors: Bike Motors - Accessories

It had the slide is made out of brass and it came stock with that filter and the jet is very nicely done with a nicly tapered needle it was worth the money And the manafold I purchased from Norm!

Last edited by MarcPhotoMan : 08-08-2008 at 09:36 PM.
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Old 08-09-2008, 10:53 PM
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Default Re: Will it hurt to increase air flow?

I saw the clip you guys talked about and adjusted it down to go along with the increase in airflow. I feel a performance increase in my 49cc as a result. Thanks!
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