XS type reed valve

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I am doing a few jobs on a friends 850 at the moment, one of which is to fit a CC reed valve. Does anybody know where I can find one of the Yamaha XS crank case breathers. Holland NW are out of stock & I can't see them on Mikes XS site.

Martyn.
 
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I am doing a few jobs on a friends 850 at the moment, one of which is to fit a CC reed valve. Does anybody know where I can find one of the Yamaha XS crank case breathers. Holland NW are out of stock & I can't see them on Mikes XS site.

Martyn.
We all want to know !
 
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You go onto Ebay, search for EGR valve in Motorcycle parts and pick one from the selection of new and secondhand. They will come with the pipes at different angles, I use the ones at 180 degrees apart fitted to a Yamaha moped or small bike.
 

baz

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You can take the Yamaha 125 valve apart and use just the half with the reed valve in
Screw it to the redundant electric start blanking plate on a 750
That way you shouldn't get it clogged up with emulsified oil because you get full heat transfer
 
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Every EGR valve I've ever seen is vacuum activated, not just a reed valve.
The EGR valves off the Yamaha mopeds I use all have an arrow pointing at the valve on the inlet port, does not matter if they originally are vacuum operated as if you blow through them using the inlet port they still work, blow the opposite way on the other port and its blocked. The XS650 valve is an EGR valve repurposed as a PCV valve, and it works. The Yamaha EGR valves have the exact same internals as the XS650 valves and are reed valves.
 
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Deets55

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I’m pretty sure some late model Triumphs use a very similar valve in their EGR/PCV loop. Maybe a Google search under that topic might yield something.
 

maylar

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Yes, Google EGR and PCV and you'll see that they are intended for very different applications. An EGR valve redirects exhaust gas back to the intake for reprocessing unburned fuel in the exhaust, to reduce hydrocarbon emissions. A PCV valve is a one way check valve to prevent pressurizing the crank case. I'm not saying they can't physically be the same valve, but every EGR I've seen is much different. I can't wrap my head around the idea of directing hot exhaust gasses through rubber hoses. But then, I'm not a professional mechanic either.

Here are the EGR and PCV valves on my Oldsmobile -

EGR

4


PCV

4
 

Deets55

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87EC8C39-CB3F-406A-9EBC-D54456274BC5.jpeg


I’m sure something like this can be modified and mounted to the old magneto area on the timing side case. Just one example, Bonneville T-100
 
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Plenty of history on this site about using the Triumph parts (which are EGR to add fuel to that fire).

We've always suggested that MikeXS was just using scooter parts or something but we could never match up the exact model or part.
 
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We've always suggested that MikeXS was just using scooter parts or something but we could never match up the exact model or part.

His prices are reasonable, to be fair.

I’d have bought from him, but being in the UK, it made more sense to find a scooter valve with the stubs at a suitable angle, on EBay.
 
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