Oil breather line routing

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I have a simple question for those of you running Amals. I got tired of struggling with the stock airbox and replaced it with a clamp-on K&N. I'm very pleased, but not quite sure how to route the small (3/8") breather line. (This is on a Combat motor with the breather in the stock location.)

I have it running under the airfilter and through the battery box area. Works ok but doesn't look quite right to me. So I was wondering how I should have done it!

thanks,
Debby
 
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Nobody knows? :cry:

The guys in our club all seem to have 850s and Mikunis so no help there either.

Oh well, not that big a deal I guess...

Debby
 
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Wish I could help because I'm a dyed-in-the-wool Amal man ( everything else looks out of place to me) but my 850 has a 750 airbox and I moved the breather outlet on my '72 750 (which has velocity stacks and extended inlets anyway!)

However, I'm exceedingly nosey. Which small pipe do you mean ? Do you have the standard set-up with a large bore pipe coming out of the separator on the back of the cases and then going through an adaptor to the oil tank ? I think the only tidy way is to keep it as low as possible until you're in the battery area and then let it find it's own way.

Do you have the single K&N with the double inlet ? I never really got mine to carburate happily with one of those. Always a flat spot at the upper mid-range if I took a big handful that I could never quite disguise by playing with needles and main jets.
 

L.A.B.

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debby said:
I have it running under the airfilter and through the battery box area. Works ok but doesn't look quite right to me. So I was wondering how I should have done it!

debby said:
Nobody knows?

Perhaps the aesthetic routing of breather pipes isn't a 'guy thing' debby?

So why not move it about until you are happy that it looks right?
 

MichaelB

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debby said:
Nobody knows? :cry:

Oh well, not that big a deal I guess...

Debby


Pushy, Pushy, Pushy
OK, Ok, you motivated me to go take another look. I have two rear breather 750's, but not set up like yours.
I have twin, splayed, Mikunis were the line spilts the carbs, up and over attaches cleanly on a horizontal plane with the top of the oil bag.

The stock one runs under the filter assembly, up the right side behind the backing plate in the front roght corner of the battery box with a tight radius to the oil bag.

With a single Mik, coming from the bag, I run it across the top of the bag, down the right side of the air cleaner to the breather.
This may not as easy with the twin Amals.

Did you pull the backing plate?
 
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Debby, on Midnite, which also has the K&N filter and no original airbox parts, I ran the 3/8 straight up between the K&N and battery box and then connected it to the 1/4 hose from the filler tube with a motormite brake booster valve.. http://www.nortonclub.com/docs/BreatherValve.pdf
The valve ends are 90 degree's from each other. Just perfect to turn the corner..

Can you believe, the ends of the valve are the same size of the hoses??

Hope this is what your looking for!
Regards! Chris
 
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That's better! :lol: Now I have some ideas to think about :D

To clarify, it has the breather in the standard Combat location at the bottom rear of the crankcase. I'm using the K&N filter that clamps onto both Amals. You do have to remove the back plate to use that filter, there's not enough clearance with the plate installed.

I didn't remember how the lines used to run with the stock airbox and didn't have any photos to check. With the clamp-on filter it does look like the easiest routing is under the filter and into the battery box in some manner. I'm just not quite satisfied with how I have it now.

Debby
 
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Roger the clarification..

My Midnite is a litter mate to yours, a 72 Combat.. Twin Twins

If my digital was in town, I would shoot some pics...
 
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debby said:
I didn't remember how the lines used to run with the stock airbox and didn't have any photos to check. With the clamp-on filter it does look like the easiest routing is under the filter and into the battery box in some manner. I'm just not quite satisfied with how I have it now.

Debby

Does this help ? Hose goes round right-hand side of air box then between box and frame tube.


Oil breather line routing


Sorry that ImageShack has made the image so small.
 
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