I have seen a check valve by motormite mentioned a couple of times in the Norton News. Any one know what this is, what does it do, where does it mount, and what are the benefits ? Also, the advice given out concerning what battery to put in a Estart was right on the money. You want to put the biggest battery in that will fit, the most bang for the buck! and keep it on a battery tender when in the garage. my latest battery came from Advance auto, Extreme magna power power sports battery AGM ETX20l. Be sure to put bigger cables on as well.
motormite
- Thread starter donmeek
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Donmeek
Try using the MikesXS650 reed valve. These are steel rather than a rubber flap and work at all RPM ranges. $18.00 US ...can't go wrong at that price. Fits up in the battery compartment and its out of the way. Do a search here at the forum on this upgrade. Link is here: http://www.mikesxs.net/products-4.html?category_id=4.7
Scroll down till you see reed valve.
Cheers
CNN
Try using the MikesXS650 reed valve. These are steel rather than a rubber flap and work at all RPM ranges. $18.00 US ...can't go wrong at that price. Fits up in the battery compartment and its out of the way. Do a search here at the forum on this upgrade. Link is here: http://www.mikesxs.net/products-4.html?category_id=4.7
Scroll down till you see reed valve.
Cheers
CNN
DogT
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It's used to prevent the crank breather from letting air back into the crank as I understand to build up a partial vacuum in the crank and thus prevent leaks due to crank pressure. Depends on the model of Commando you're talking about, there were several breather arrangements through the years. It doesn't seem to work on the early timed breathers which were not too effective anyhow, but as a later upgrade off the timing cover. Do a search on breather, and you will have many days of reading.
Dave
69S
Dave
69S
It's a one way flapper valve that goes in the crankcase breather hose. It's supposed to keep the crankcase pressure down to help stop oil leaks from a pressurized crankcase. When the 2 pistons fall the crankcase is pressurized the pressure goes out the breather hose, when the pistons rise no air can be drawn back into the crankcase as the flapper valve is one way. Next down stroke there is little in the cases to make pressure, etc. The reed type valves are far superior to a flapper valve as stated above. Make sense? Graeme
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Donmeek
I believe originaly it was an automotive part used for a brake master cylinder vacuume booster for a car. This was used by one of the INOA members who published it in one of the Norton News articles (don't ask me which) and they recommended this unit as a good cheep mod to do for your commando. Years go by and we have others who recommend better units to keep a negative pressure inside the crankcase of your commando while under speed. Go and use the search of this site, which will give you hours of info on this subject and YOU then can make an educated decision on what is best.
Regards,
CNN
I believe originaly it was an automotive part used for a brake master cylinder vacuume booster for a car. This was used by one of the INOA members who published it in one of the Norton News articles (don't ask me which) and they recommended this unit as a good cheep mod to do for your commando. Years go by and we have others who recommend better units to keep a negative pressure inside the crankcase of your commando while under speed. Go and use the search of this site, which will give you hours of info on this subject and YOU then can make an educated decision on what is best.
Regards,
CNN
is the mk111 a candidate for this mod? have noticed oil seeping in places where never before. checked all head bolts, studs, etc, all tight, but when running here in Fla, after an hour or so, have seepage. will sit in the driveway for an hour (with a fan blowing) at idle and no sign of oil anywhere. Have owned this bike for 36 years, and this is something new. too much pressure with the heat? don't know. asking for help. Jim Comstock, where are you?
Yes I have a mk3 and fitting a reed valve non return valve from a Ducati stopped all the annoying little weeps. Most here use the xs650 reed valve unit. The Ducati valve needs an adaptor turned up to allow it to be mounted in line in the breather hose. But I think the xs650 one has a hose spigot each end and is easier to mount without making any fittings. Graeme
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I use the $5 Dolomite one way valve, instantly eliminated all little oil leaks around the motor.
Some speculate this does not last as long as the all metal xs650 one, but I have had mine in place for 18 months,
and how can you beat $5
here is the link http://www.amazon.com/Dorman-80190-Brak ... B000CO9730
Some speculate this does not last as long as the all metal xs650 one, but I have had mine in place for 18 months,
and how can you beat $5
here is the link http://www.amazon.com/Dorman-80190-Brak ... B000CO9730
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donmeek said:
The answer is yes.
Many miles on the Norton will start to have gasses passing past the pistons from wear. Remember the engine is an air pump. What is happening at the top: Air/Fuel/Spark/Bang/Push, the bottom of the piston is pumping air as well through that effect. If it is not relieving equal amounts, then pressure builds up. The first notice is that you may have old weeping past into the points cover then when you change that you find oil passing by your Tach housing, change that, then your Main bearing oil seal, etc, etc. You are chasing the demon thinking that is seals but it is the pressure that builds and not venting which pushes excess gasses out of the crankcase any way it can. This mod you inquire about will help, as will other more modern systems. It depends on how deep is your pocket book or how good of a mechanic you are. :wink:
Best of luck
CNN
the MKIII has already a rudimentry pvc system in place.
The crankcase has a big breather pipe exiting the rear inboard side of the timing case. It routes to the oil tank neck. Then there is a connection from the top side of the oil tank to a tubular metal can gizmo which vents into the clean air side of the air box and is also teed into the balance pipe between the Amals. What is wrong enough about all this to necessitate any additional anythings? I don't get it. Is the volume change within the crankcase more than the stock setup can handle? Is that it?
Best Regards,
No Discernable Leaks in RI.
The crankcase has a big breather pipe exiting the rear inboard side of the timing case. It routes to the oil tank neck. Then there is a connection from the top side of the oil tank to a tubular metal can gizmo which vents into the clean air side of the air box and is also teed into the balance pipe between the Amals. What is wrong enough about all this to necessitate any additional anythings? I don't get it. Is the volume change within the crankcase more than the stock setup can handle? Is that it?
Best Regards,
No Discernable Leaks in RI.
The valve needs to be as close as possible to the crankcase to be effective, that is why the one designed by Jim Comstock for CNW is right at the bottom of the crankcase. That vent placed at the bottom will get a lot of oil thrown at it as well as air, so it must be routed back to the oil tank and the oil tank must be vented out (or if you have a social fiber, back to the intake so it is burned by the engine, same as a PCV valve in a car)
Jean
Jean
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donmeek said:
Where are you in Florida? There are several of us across the state on the forum...
FWIW my motormite only lasted about 200 miles. That seems typical, although some have reported theirs lasted much longer. Was very obvious when it failed as oil started coming out of all sorts of places.
XS650 reed valve is only about $10 more. Works a charm on my bike.
Cheers,
- HJ
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My little motormite valvey thing has been up near the oil tank for a good 6 yrs. and I was carefull to put no strain on it as it is made of thin plastic. Just received my XS 650 reed valve thingy from Mike's and will attempt the changeover shortly ,should be a straight substitution ,does the lipped brass -coloured larger spigot go towards large motor hose and the smaller silver unlipped spigot go towards the oil tank ? No in or out markings.
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Yes, just blew into brass end and it now seems obvious, I fear there will be no room to mount it in line near oil tank as it is much larger ,any ideas on that ? The motormite is way smaller and fits easily there.
ok guys, appreciate all the input. installed a motormite right off the timing cover vent. the results were amazing. no weeping anywhere, and the tach even settled down where the needle doesn't jump around a bit. i was getting a little bit of backfiring, not much, just a little pop pop when rolling off the throttle after taching up pretty good, and that too seems to have gone away. put the motormite in as a test, because of cost and availability (advance auto had it in stock) but will switch to a mikes in the future. oh, in response to the post about mk111 venting, my fault, as i did not specify that i removed all that junk many moons ago and put a single mikuni on
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Krank makes an neat Al cylinder inline PCV I used on Peel that worked a dry Combat treat, mounted up near oil tank, but costs ~$90. I got mine from Kenny Dreer. Will use exhaust eductor on Peel so oil leaking tack drive Trixie Combat will inherit soon. Trixie stays mostly dry until 5000 rpm or so, then messes her cases, which are still as factory issued front oil drain and secondary breather hose return path to tank. Likely mostly HD's are the market for Krank. Much as it may recoil us, HD's are closest relatives running around.
http://www.3000gtvr4.com/index.php?opti ... &Itemid=54
http://www.3000gtvr4.com/index.php?opti ... &Itemid=54
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Torontonian said:
Mount as close to the timing cover as possible. If you mount it all the way over at the oil tank, the tubing itself will flex as you draw a vacuum and limit your results.
I have mine mounted on a short (1 1/2") clear tube coming out of the timing cover (clear so I can inspect the line isn't clogged with oil, stole the idea from swooshdave I think), with the output a opaque long breather line going to the oil tank.
IMHO the XS PCV is the best easy upgrade for the Commando. Ludwig's ingenious design or the CNW mod clearly superior but involve machining with the engine out. If I should ever have a need to take the engine out and split cases again, will go down one of those routes.
Cheers,
- HJ
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