The original sump reed valve breather by Leo Goff

I first heard about a reed valve breather being used on a Norton back in the mid 1980s when Leo Goff mounted one on his Champion 750 140mph dragster. I think this info was printed in the "Norton News" monthly of the time. So I called him up and asked for details. He said it would save some HP. I went to Napa auto and ordered the parts for my road racer. I plumbed up the bottom of the sump with the petal reed valve and ran a clear hose to the oil tank. When I started it up I was pleased to see excess oil pump through the hose up to the oil tank - another of many tricks I experimented with in my search for more power. To my knowledge we were probably the only two who had adapted reed valves to the Norton sump back then. But there was no commercial interest at the time so thats as far as it went. Now you see them all over this forum. Just a reminder that Leo was the 1st and deserves credit for it and a thank you for the help and advice he provided. Below is one plumbing option for blowing excess oil out of the lower rear sump - with Steve Maney or stock Combat cases.

From the pictures on the TGA site Molnar has included the rear breather hole on his 'race' cases, but not on his 'road' cases!

I guess you would have to ask for it to be added if you wanted a rear of sump mounted reed valve breather on a road bike, or more specifically a bike that uses a Commando primary case!

Well ok not Commando related but i clearly remember that a dear friend of mine Santa Cruz Phil T. had in about 87ish a full Reedcase of a two-stroke welded on the case of a B50 circuit racer.
Back then being a youngster i did not understand unfortunately the impact of such things. But i still clearly remember that Beeza hauled ass!

Kind regards

Christian

Jim, btw a hint off topic but regarding your needed weld work on the heads, Puccio in San Jose seems to still active.

SteveA said:

From the pictures on the TGA site Molnar has included the rear breather hole on his 'race' cases, but not on his 'road' cases!

I guess you would have to ask for it to be added if you wanted a rear of sump mounted reed valve breather on a road bike, or more specifically a bike that uses a Commando primary.

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SteveA said:

From the pictures on the TGA site Molnar has included the rear breather hole on his 'race' cases, but not on his 'road' cases!

I guess you would have to ask for it to be added if you wanted a rear of sump mounted reed valve breather on a road bike, or more specifically a bike that uses a Commando primary case!

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How far rearward could the breather protrude off the back of the lower case before interfereing with something? You might be able to mount a breather by drilling and threading just one hole. Give me a clearance dimension and I'll check it out.

jseng1 said:

How far rearward could the breather protrude off the back of the lower case before interfereing with something? You might be able to mount a breather by drilling and threading just one hole. Give me a clearance dimension and I'll check it out.

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Jim, I have a Rickman with the motor mounted vertical like an Atlas, and I already have a Comstock supplied CNW style read on the back of my Maney cases, so my situation is irrelevant to pretty much all other members here.

Since Maney cases are no longer available I was looking at what is available, and that takes you to TGA/MPL. I was just surprised to see the rear case fitting was deleted on the 'road' cases!

I was thinking about customers who might want an easy setup that only required one threaded hole in the lower rear left case. The hole would be 1/2" fine US threads and it would go where the Combat/Maney fitting is now but it would extend the breather backward another 1/2". You would just screw in the assembly with teflon tape and a locknut against the case.

jseng1 said:

I was thinking about customers who might want an easy setup that only required one threaded hole in the lower rear left case. The hole would be 1/2" fine US threads and it would go where the Combat/Maney fitting is now but it would extend the breather backward another 1/2". You would just screw in the assembly with teflon tape and a locknut against the case.

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It’s tight in there Jim. My cNw unit fouled. That’s with Maney cases and a TTI box, both thicker than stock I guess, but it goes to show how tight it is.

It‘s also difficult to keep things hidden there tight, your 1/2” fitting would definitely need lockwiring.

Fast Eddie said:

It’s tight in there Jim. My cNw unit fouled. That’s with Maney cases and a TTI box, both thicker than stock I guess, but it goes to show how tight it is.

It‘s also difficult to keep things hidden there tight, your 1/2” fitting would definitely need lockwiring.

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Yes, that TTi box takes a lot of space, I had to 'relieve' mine to fit the Rickman frame boss.

But in contrast, with Maney cases, TTi box and the same design breather I have plenty of space with the extra crankshaft centre distance!

I am using Nordlock washers to keep the breather 'box' closed tight, because it did come loose!

I filed little ‘v’ shapes in the Allen heads then centre punched the material in the v making it impossible for the Allen head fasteners to come loose, see post #63 below.

I was very pleased with myself, right up to the point I realised I didn’t have enough space between crankcase and box, so it had to come off anyway !