CV Mods

yooper trooper · Feb 25, 2023

Getting my 1973, 750 ready for Spring....last year was a bummer due to some medical problems so the bike sat

Questions I have right now concern crank case venting. Placing a PCV valve in between the crankcase and the oil tank looks to be a common mod. Good idea?? Also ran across some posts on installing a catch can somewhere. I'd be interested in seeing some photos of that.

Deckard · Feb 25, 2023

With your year engine, the CNW reed breather would be your best solution. The site says for 1972 750, but I believe 1973 750 would be the same. If your current breather is located at the rear of the crankcase, then it is the same.
Currently out of stock, call for update when available.

1972 Engine Breather Modification

Experience an increase in engine performance Eliminate persistent leaks at gaskets, seals, tach drives, head, crank case joints and more Lower the operating temperature of the engine oil The valve can operate consistently during a far higher rpm range than the Commando engine can ever reach The...

coloradonortonworks.net

yooper trooper · Feb 25, 2023

Deckard...

"There is one Commando engine that was built that will allow the cNw breather to be installed without taking the engine apart. This is the engine built in 1972 that originally has a large tubular breather installed on the backside of the cases. So it’s located inbetween the transmission and the engine. By removing this original breather and installing our model you will get all the benefits these well engineered breathers offer".
Copied from CNW site..this is the engine I have so this will work. If it does what it's advertised to do I'll most likely go with it.

L.A.B. · Feb 25, 2023

yooper trooper said:
Getting my 1973, 750 ready for Spring...

Your "1973" model "built in 1972" although perhaps titled/registered as 1973 it appears to be built to '1972' (750 MkIV) specification according to your avatar picture (if the engine and frame plate numbers are before 212278) although as far as the breather is concerned it would be the same.

baldy · Feb 25, 2023

I have the Mike's xs Reed valve breather installed. It's not as pretty as the cnw but it's alot cheaper and seems to work ok.

Deckard · Feb 25, 2023

yooper trooper said:
Deckard...

"There is one Commando engine that was built that will allow the cNw breather to be installed without taking the engine apart. This is the engine built in 1972 that originally has a large tubular breather installed on the backside of the cases. So it’s located inbetween the transmission and the engine. By removing this original breather and installing our model you will get all the benefits these well engineered breathers offer".
Copied from CNW site..this is the engine I have so this will work. If it does what it's advertised to do I'll most likely go with it.

It does as advertised and is the best solution as it will replace your current breather and render a clean solution. In line breathers may work but are clutter. You can't do better than this and you're done. Just do it......

CV Mods

yooper trooper

Deckard

1972 Engine Breather Modification

yooper trooper

L.A.B.

Moderator

baldy

Deckard

Similar threads