GB500guy
Well-known member
Butchered Dream 50 airbox healed
I'm a stickler for air intake/filter systems - I hate loud intake noise plus I want good air filtration, especially on a bike with rare and hard to find engine parts that can be quickly worn out by dirt passing through shitty aftermarket filters. So one problem I saw right away was that a previous owner had fitted an oversized carb - a logical and common mod to match to the 89cc overbore kit - but in adapting it to the stock air box they had taken the sleazy route of attacking the box with a Sawzall to accommodate a miserable dirt-passing performance-killing screen and gauze (think K&N style) "pod" filter. In a hurry to heal the damage I forgot to take a pic of the "before." But basically the front of the airbox was chopped out leaving the "filter" no longer enclosed.
Please everyone, do not install one of these miserable things, your engine deserves to inhale air that actually has the dirt filtered out:
So by patching in some PVC and polyethylene plate material I reconstructed the original airbox and added a PVC pipe manifold to connect to the air tube from the carb.
Inside view-
The airbox side cover was completely missing so I fabbed one from thin PVC plate and added foam weatherstrip gasket-
I soldered a brass ring onto a paper filter from a Honda industrial engine and added a sponge neoprene gasket-
A piece of rubber tubing behind the filter serves as a "spring" to hold the filter against the carb end of the airbox-
The completed airbox now supplies well-filtered air to the carb although intake noise at WOT is a bit much. I'll add some sound deadening foam inside and out to cut down the noise.
For now the bike is running great with just a bit more carb work needed before moving onto cosmetics. I'm having fun!! Thanks for following along.
-Bill
I'm a stickler for air intake/filter systems - I hate loud intake noise plus I want good air filtration, especially on a bike with rare and hard to find engine parts that can be quickly worn out by dirt passing through shitty aftermarket filters. So one problem I saw right away was that a previous owner had fitted an oversized carb - a logical and common mod to match to the 89cc overbore kit - but in adapting it to the stock air box they had taken the sleazy route of attacking the box with a Sawzall to accommodate a miserable dirt-passing performance-killing screen and gauze (think K&N style) "pod" filter. In a hurry to heal the damage I forgot to take a pic of the "before." But basically the front of the airbox was chopped out leaving the "filter" no longer enclosed.
Please everyone, do not install one of these miserable things, your engine deserves to inhale air that actually has the dirt filtered out:
So by patching in some PVC and polyethylene plate material I reconstructed the original airbox and added a PVC pipe manifold to connect to the air tube from the carb.
Inside view-
The airbox side cover was completely missing so I fabbed one from thin PVC plate and added foam weatherstrip gasket-
I soldered a brass ring onto a paper filter from a Honda industrial engine and added a sponge neoprene gasket-
A piece of rubber tubing behind the filter serves as a "spring" to hold the filter against the carb end of the airbox-
The completed airbox now supplies well-filtered air to the carb although intake noise at WOT is a bit much. I'll add some sound deadening foam inside and out to cut down the noise.
For now the bike is running great with just a bit more carb work needed before moving onto cosmetics. I'm having fun!! Thanks for following along.
-Bill
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