Important to check

[Jess]

As riding season approaches in North america and we are getting our bikes from hibernation, an important, and often overlooked item is the check valve on the carby.

This item is critical to the life of your engine!

It is the aluminum valve that screws into the carby close to radiator. It is connected to the metering pump and delivers oil to the float bowl and then on to the engine.

Simple check... unscrew, remove from line, place to your lips and blow, then suck...

Blow... air should pass.

Suck... Check valve should check.

If you can draw ANY air when you suck... replace valve immeadiately if not sooner.

This check should be done at every service interval or oil change as I am seeing more and more of these valves fail after 30 plus years...

Just a helpful hint...

Best,

Jess

[Crusader]

Yes good tip, i just replaced mine with a NOS one from Sam, 40USD but worth it!!!!!!!! cheaper then a proper unit!!!

[aerologic]

I too got a replacement from Sam. I had tested my valve with the blow/suck method and it seemed like I had to blow pretty darn hard to get air to flow but since I had nothing to compare it with I got one from Sam. The replacement from Sam was similar so I guess I have an extra one now. Can't hurt to have a spare!! I also got a new pump since I didn't see any flow from the old one. I haven't tested it yet. (I still am putting oil in the gas while I test this)

[aerologic]

Followup question: What is good to buy, where to buy, a graduated cylinder, for the testing of the metering pump per the Service Manual? Is this a WalMart or Kroger type of thing? I can rig up a connection. I just don't want to buy some expensive glass graduated cylinder from some Chem Lab supply company for $100.00.

[Jess]

Dave,

I just use the largest plastic syringe I can buy at the Pharmacy...

Best,

Jess