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1978 CX500 "The Grub", 1983 GL650I "Nimbus"
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Discussion Starter · #42 ·
Depending on the year of the engine the crankcase may be vented through the cylinder heads, CX500s, through the pulser cover, GL500 and others, and through a bottle breather at the timing inspection port.
i think my cx500 is vented through the cylinder head, though i'll have to check. its been awhile since ive looked under the covers.

before you say the '78 didnt have X style, i had to swap an '80 engine onto the frame after i locked the '78 engine up...

I know the gl650's that i have use the bottle breathers.
 

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CX650 motor project into a CX500 Turbo Frame - ongoing
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i think my cx500 is vented through the cylinder head, though i'll have to check. its been awhile since ive looked under the covers.

before you say the '78 didnt have X style, i had to swap an '80 engine onto the frame after i locked the '78 engine up...

I know the gl650's that i have use the bottle breathers.
@SirFoxx Do you still have the valve covers from the 78? @Molten Stenberg cracked one of his and was looking for a set. Any set really.
 

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I know the gl650's that i have use the bottle breathers.
Bottle Breather and the vented pulser cover.
The bottle on the inspection port is really to increase condensation of vaporized oil before it passes to the reclamation system. It's a secondary vent, at most.
 

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Discussion Starter · #48 ·
Bottle Breather and the vented pulser cover.
The bottle on the inspection port is really to increase condensation of vaporized oil before it passes to the reclamation system. It's a secondary vent, at most.
reclamation system..?
 

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OIl vapors and moisture from the crankcase are directed to a collector under the air filter housing. The volitiles are pulled in with combustion air and burned. The heavier junk, including water, is retained and drained at each oil change (if you're doing your proper maintenance.) The GLs have a more elaborate separator and reservoir. I believe the bottle is intended to help separate the oil vapor and return it to the crankcase.
 

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Discussion Starter · #50 ·
OIl vapors and moisture from the crankcase are directed to a collector under the air filter housing. The volitiles are pulled in with combustion air and burned. The heavier junk, including water, is retained and drained at each oil change (if you're doing your proper maintenance.) The GLs have a more elaborate separator and reservoir. I believe the bottle is intended to help separate the oil vapor and return it to the crankcase.
oh. my cx500 is just venting to the atmosphere lol. i think i have one of the hoses still hooked up tho.
 

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I hope it doesn't vent directly to atmosphere, or you're sucking in dust and contaminating your oil.
If you have hoses, but no collector, you're leaving a trail of oil drips somewhere.
 

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Discussion Starter · #52 ·
I hope it doesn't vent directly to atmosphere, or you're sucking in dust and contaminating your oil.
If you have hoses, but no collector, you're leaving a trail of oil drips somewhere.
where are you supposed to run it to with murray carbs?
 

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A filtered catchcan/separator might just work...

You can buy suitable pod filters for the application.
 

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Discussion Starter · #54 ·
A filtered catchcan/separator might just work...

You can buy suitable pod filters for the application.
i dont think the average schmoe who buys his kit acutally routes the crankcase vent to the suitable place
 

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You're likely right.

Murray has suggested a setup that places the end of the breather against the {carb} pod filter so that the engine will rebreathe the resulting fumes.

I prefer a proper breather separator.

My thingy uses one that has drains with caps that is drained at service per the factory item.

It's a labrynth type to maximise surface area for condensation to take place. Made from PVC pipe and capd.

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2021 Benelli Leoncino - 2017 CSC RX3 - 2017 SSR Buccaneer 250i - 1979 CX650 Street Scrambler
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i dont think the average schmoe who buys his kit acutally routes the crankcase vent to the suitable place
I did. Get a long hose and put a small filter on the end of it. Route the hose between the "V". It's so long that oil vapor will never make it to the filter, but that doesn't keep the engine from breathing properly.

Charles.
 

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I've seen designs using a T-connector. Up to a small pod filter, as Charles described. Down to a capped tube extending past the swing arm pivot, similar to the stock airbox drains. It's long enough to function as a reservoir, if it's emptied frequently.
 

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Discussion Starter · #58 ·
question--

are the 650 headers different than the 500, or can i reuse my 500 headers?
 

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500cc headers have a smaller internal diameter and will choke the 650 motor. The 650 headers are also longer to accommodate the extra height of the cylinder heads. While you can use 500 headers, you will be down on power (I verified this by accident) and your collector will point downwards at the back, causing your mufflers to not line up with their mounting brackets.

Charles.
 

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Discussion Starter · #60 ·
500cc headers have a smaller internal diameter and will choke the 650 motor. The 650 headers are also longer to accommodate the extra height of the cylinder heads. While you can use 500 headers, you will be down on power (I verified this by accident) and your collector will point downwards at the back, causing your mufflers to not line up with their mounting brackets.

Charles.
gotcha. what would a be a decent set of mufflers to use? I currently have emgos on my cx500, and i think theyd be a bit restrictive as well for the 650
 
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