XS type reed valve
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If you can whittle metal somewhat, one of the cheapest reed sets i've come across is the inlet reed block for a mini moto bike. Looks very similar to the reed block in the CNW breather. I got two off ebay for less than £5
baz
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Erm the one I had got thrown out a couple of years ago
Basically it's the hose fitting on the torch end of an acetylene hose
I think I removed a wire clip to remove the threaded end
The barbed end I made an interference fit into the timing cover blanking plate
I had a hose from this teed into the rotrary timed breather from the camshaft so both were combined
When I fitted the Alton I initially went back to just the standard rotary breather but I started getting small oil leaks from the crankcase and cylinder base
So I fitted the Yamaha one in its place
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You still have to build a housing like Jim Schmidt did. At that point unless you have a mill you might as well just buy a complete valve.
cliffa
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No problemo. I can see that would be pretty expensive in the end. I bought one from Mikes XS in the past. Really terrific service I have to say. When you look inside they are all the same, there is just a stainless reed petal, and a rubber seal. Have you considered the Comstock / NYC valve ? that is really the cream of the cropCliff, thanks for the eBay links. However, with currency exchange, shipping, customs [lots of reports of the agents taking advantage of Brixit] I can probably buy the 90 degree angle unit, new from M.A.P. Cycle for about the same money. [Thanks for the links htown16] When I reported the $92 price for the straight through valve, I had not done any price comparisons. Turns out the first link Google sent me to, is way over priced. I just found another source with USA warehouse priced at a more reasonable $42.13
MegaZip sourced Air Injection Valve
That was only the 2nd place I found. Hopefully it's available elsewhere for even less.
Having read MikesXS installation instructions for the 90 degree angle valve, installing it "Intake side up" on a Commando would be difficult. I believe that the straight through Yamaha valve offers more options regarding where to install it.
Dave, The eBay links below suggests that Mike's valve is used on Kinroad & Skyteam scooters. Probably used on others as well.
90 Degree EGR aka Air Injection Valve
Less Expensive 90 Degree Air Injection Valve
Both the above links refer to these as EGR valves, so I understand where kommando got the term. Without either a repair manual, parts catalog or at least an exploded view, I can not determine how they are originally used. That said, I've never seen a reed valve used in a real EGR [exhaust gas re-circulation] system. True EGR meters a small amount of exhaust gas back into the intake manifold. This is done only when the throttle is open and the engine is fully warmed up. The purpose is to lower the combustion chamber temperature. This is done to reduce oxides of Nitrogen from being released out the exhaust.
Air Injection systems simply use the weak vacuum created between exhaust pulses in a piston engine to draw filtered air from the air cleaner into the exhaust. This is done to help burn any un-burned hydrocarbons leaving the engine. The air injection valve simply prevents the exhaust gases from backing up into the air cleaner.
Two different systems meant to do two different jobs. I suspect that calling these valves EGR valves came from a poor translation of Chinese, Japanese or Korean into English.
https://nycnorton.com/product/reed-valve-breather-kit/
Although I think grandpaul's is realy neat, and probably stops the condensation that can build up in some remote locations.
Cheers,
cliffa.
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baz
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I'd guess it depends on your climate and whether you do long or short trips
Maybe someone that has one will chime in
Cheers
cliffa
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As kommando says...
www.mikesxs.net
orientation of the outlet it also advised to be downwards.
Yamaha XS650 Parts & Vintage Yamaha Parts - MikesXS.com
Mikes XS is the leading supplier of vintage parts for Yamaha XS motorcycles. Filters, Chassis, Brakes, Wheels, Suspension and Engine products are just some of the items we carry.
www.mikesxs.net
orientation of the outlet it also advised to be downwards.
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I have one on a Triumph twin and I oriented the outlet pipe vertically upwards.
Seems like obviously correct way, to me.
Seems like obviously correct way, to me.
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Correct. I was merely pointing out another source available to those of us in North America. The valve originally linked to does not ship to the USA. I really like Paul's style of valve. However, I do not wish to drill or drill and tap the crankcase. I prefer to not modify the crankcases to allow the bike to be later converted back to pure stock, if I desire. I figure the day may come in the future, where I am no longer interested in speed. [Parish the thought!
]Almost forgot, my local Yamaha dealer quoted me $40.99 for the YZF-R125 air injection valve I mentioned on the previous page. He said it might take up to 60 days to obtain. That saves a bit of money and eliminates shipping and customs issues.
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I have mine as close to the crankcase as possible but then I have a 72 so that’s possible. When I took it last apart there was no gunk at all. Further away you are from the engine may be different.
Lineslinger
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The XS I installed didn't clog but the line on the inlet side of the valve did. It had been sitting for a while during the winter and had the oil/water goo clogging it.
Compressed air cleared it.
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Who did you purchase that valve from? Mikes XS? I ask, because in Mikes installation instructions, there is mention of an early and a late style. Both are shown but it doesn't clarify which is early and which is late. One style has inlet and outlet at 90 degrees. The other style has both inlet and outlet pointing the same direction, similar to your valve.
grandpaul
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Man, I REALLY like those oil lines.
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Lineslinger,
I use to have a Mike's XS reed valve up in the battery compartment but I soon discovered that the oil in the tank would get milky and when drained when doing an oil change, there would be water at the bottom on the oil tank. That reed valve needs to be physically attached to the engine to keep the condensation at bay.
I went to the Comstock design at the back of the 850 engine and never had issues since. the heat from the engine helps cook off any condensate. Where you mounted it up near the oil tank makes it act like a water trap for condensation, IMHO.
I don't drain the wet sump plug either with the Comstock design, as it quickly discharges any excess oil in the sump rapidly back into the oil tank. About 30 seconds is all it takes and then all I see after that is the steady percolator pattern of oil return from the rear tube from the oil pump return line. YMMV
Cheers,
Tom
I use to have a Mike's XS reed valve up in the battery compartment but I soon discovered that the oil in the tank would get milky and when drained when doing an oil change, there would be water at the bottom on the oil tank. That reed valve needs to be physically attached to the engine to keep the condensation at bay.
I went to the Comstock design at the back of the 850 engine and never had issues since. the heat from the engine helps cook off any condensate. Where you mounted it up near the oil tank makes it act like a water trap for condensation, IMHO.
I don't drain the wet sump plug either with the Comstock design, as it quickly discharges any excess oil in the sump rapidly back into the oil tank. About 30 seconds is all it takes and then all I see after that is the steady percolator pattern of oil return from the rear tube from the oil pump return line. YMMV
Cheers,
Tom
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Ok, now I want to know more about what you did there. I assume you have a strainer and standoff going into the sump?The 90 is the older style and the one I used for my sump plug version.
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