Reed PCV valve

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Connects from crankcase to oil tank.

http://www.mikesxs.net/products-40.html#products

Reed PCV valve


CNW has one also.
 
I was under the earlier impression that people had been told to mount the PCV valve into the breather hose running from the filler cap down to the air box. (This caused me to wonder about the oil cap airseal effectiveness.)

So where does it go into?

Hose #1 ( " Breather Pipe/Timed Breather, 3' " ) or...
Hose #14 ( " Breather Hose, 10" " )
Reed PCV valve
 
hi mehavey,if your engine has the timed breather from the end of the cam i cant see fitting a reedvalve into hose#1 having any effect,if your engine has the breather on the rear of the crankcases or the rear of the timing cover this is where it needs to go,then into the oil tank
 
MEHAVEY said:
I was under the earlier impression that people had been told to mount the PCV valve into the breather hose running from the filler cap down to the air box. (This caused me to wonder about the oil cap airseal effectiveness.)

So where does it go into?

The purpose of a PCV valve is to prevent the crankcase from filling with air on the upstroke of the pistons, but yet allow air to escape on the downstroke. The valve needs to be inline of the breather hose. That's the one running from the crankcase to the top of the oil tank. The tank still needs to be vented. It is not to be air tight.
 
But if Chris is right, placing a PCV in line with the (#1) timed breather hose above in a `71 (which comes off the front of the crankcase) will have no effect.

Reed PCV valve


(Is that right ......???)
 
It will have some effect, no doubt. If it were mine, I would block off the original port and vent per Old Britts mod:
Reed PCV valve


I had a 1969 Commando with the timed breather thirty-eight years ago . I don't recall how effective that setup was. From what I've been reading here, it could use some help. I guess if you didn't have any oil leaks there would be little need for a PCV valve.
 
I know this is an old thread, but I am having trouble finding an answer.

I have a '71 Commando with the breather on the drive side of the crankcase and would like to install a Reed PCV Valve from mikes XS. If I block off the existing breather and install a breather line where the blank plate is with the Reed PCV Valve, do I need to drill holes into the timing side crank case half?? I am hoping not to take the entire engine apart to solve the crankcase pressure issue.

Thanks
Dan
 
o0norton0o said:
http://www.accessnorton.com/new-member-with-1970-commando-t21402-30.html

half way down the page is the picture of my timing side with the cover off and the hole's that I drilled.

Did I need to drill any holes?... maybe not, but it hasn't proved to be a problem so far...

Gotcha. So a full tear down and splitting the cases would be necessary :wink:

Cheers
 
danfr said:
I know this is an old thread, but I am having trouble finding an answer.

I have a '71 Commando with the breather on the drive side of the crankcase and would like to install a Reed PCV Valve from mikes XS. If I block off the existing breather and install a breather line where the blank plate is with the Reed PCV Valve, do I need to drill holes into the timing side crank case half?? I am hoping not to take the entire engine apart to solve the crankcase pressure issue.

Thanks
Dan

I would say, in your case, if you are reluctant to drill holes anywhere, except perhaps in the case of a complete rebuild, that you should block off the timed breather, and install one of comnoz's sump plug/breather units.

Slick
 
yeah, if your bike doesn't have an early frame with the cross member near the sump plug, you can buy one of Jim comstock's sump plug reed breathers and just bolt it on with ZERO modifications... It also breathes directly from the crankcase which makes it more efficient.

If you have an early frame bike (like I do) the sump breather won't fit, so you are tasked to modify stuff. I drilled 2 crankcase holes without disassembly. I used a shop vac with a homemade funnel tip to pull the chips off the drill as I went. I cleaned the timing side as best I could before reassembling it. I also did 2 quick oil changes so I could remove any suspended aluminum flakes in the oil and cleaned out the sump screen and oil tank. There will be a certain amount of aluminum that will go into your case if you drill it without disassembly. I noticed a few flakes in my sump screen and some metalic glow in the oil immediately after running the bike after the modification, which prompted the 2 quick oil changes to flush as much out as possible... So you've been warned... It's possible to do, but not fool proof...
 
danfr said:
I know this is an old thread, but I am having trouble finding an answer.

I have a '71 Commando with the breather on the drive side of the crankcase and would like to install a Reed PCV Valve from mikes XS. If I block off the existing breather and install a breather line where the blank plate is with the Reed PCV Valve, do I need to drill holes into the timing side crank case half?? I am hoping not to take the entire engine apart to solve the crankcase pressure issue.

Thanks
Dan

Does it have the plate on the back of the timing side to mount a maggie, if it does take the plate off and mount the reed valve there or go for Jims set up, thats if the frame isn't in the way.

Ashley
 
ashman said:
danfr said:
I know this is an old thread, but I am having trouble finding an answer.

I have a '71 Commando with the breather on the drive side of the crankcase and would like to install a Reed PCV Valve from mikes XS. If I block off the existing breather and install a breather line where the blank plate is with the Reed PCV Valve, do I need to drill holes into the timing side crank case half?? I am hoping not to take the entire engine apart to solve the crankcase pressure issue.

Thanks
Dan

Does it have the plate on the back of the timing side to mount a maggie, if it does take the plate off and mount the reed valve there or go for Jims set up, thats if the frame isn't in the way.

Ashley

It has the flat plate on the back of the timing side. I also noticed the hole next to the camshaft that leads into the cases. That's why I was curious if i needed to drill the holes. If there's a hole into the crankcase, then what are the addition holes for? Oil entering and returning i suppose. I was hoping to take off the flat plate on the rear of the timing case and instal a reed valve there and have that line head to the oil tank.
 
It has the flat plate on the back of the timing side. I also noticed the hole next to the camshaft that leads into the cases. That's why I was curious if i needed to drill the holes. If there's a hole into the crankcase, then what are the addition holes for? Oil entering and returning i suppose. I was hoping to take off the flat plate on the rear of the timing case and instal a reed valve there and have that line head to the oil tank.[/quote]


Take the plate off and mount it on that plate and remount the plate, a easy job and no swaf getting into your motor.

Ashley
 
danfr said:
I know this is an old thread, but I am having trouble finding an answer.

I have a '71 Commando with the breather on the drive side of the crankcase and would like to install a Reed PCV Valve from mikes XS. If I block off the existing breather and install a breather line where the blank plate is with the Reed PCV Valve, do I need to drill holes into the timing side crank case half?? I am hoping not to take the entire engine apart to solve the crankcase pressure issue.

Thanks
Dan

You actually have a ideal situation but you have to remove the rotating valve from your left side cam breather (I went one step further and knocked out the plate with two holes as well with a punch - not absolutely necessary). Then run the Yamaha 650 valve between the left side case and the oil tank. Plug the big air vent between the timing chest and the sump and you've got the hot setup. Then you have to stay with hollow cams. I've done this on my Atlas and it works great.
 
Time changes everything. Years ago, this forum was rife with complaints about leaking crankshaft seals. Replace, rinse, repeat, seemed to be de rigueur. An elusive search for an unobtainable seal that would stop the leaks from the crankcase into the primary was made by many . At the time, many were skeptical about using a reed valve for crankcase ventilation. Now, a reed valve is the accepted method of prepping a Commando. Of course, there will always be someone who is convinced a Dodo bird can fly. Next thing you know someone will discover the stock Norton brake master cylinder bore is way too big.
 
I don't see the need to eliminate the timed breather to add something else. I run 2 reed breathers. One off the lower rear left up to under the seat where it take the natural right angle to the oil tank, and another reed(from Grandpaul) off the timing side it the old mag area, or the proposed start area the never transpired. It all depends who you talk to. Anyhow, it doesn't matter.

The point is, if one is good then why not 2. People wonder if it is better to go off the crankcase or the timing chest. I say both.
 
I have always run the timed breather vent tube on my 71 to the atmosphere. I route it down through the gearbox gap and cut the tube at an angle to induce draft just like the old time automotive draft tubes. However, the biggest help for oil leaks on my bike, 34k miles, was the oil shut off ball valve. Believe it or not my bike does not mark its spot anymore.
 
pete.v said:
I don't see the need to eliminate the timed breather to add something else. I run 2 reed breathers. One off the lower rear left up to under the seat where it take the natural right angle to the oil tank, and another reed(from Grandpaul) off the timing side it the old mag area, or the proposed start area the never transpired. It all depends who you talk to. Anyhow, it doesn't matter.

The point is, if one is good then why not 2. People wonder if it is better to go off the crankcase or the timing chest. I say both.

Great minds think alike... You seem like a very smart guy... Oh btw, I have my breather set up exactly the same way!!! :lol:
 
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