I saw the add on ebay so I asked him about my problem.
Here is what he said->
Have you fitted and used the new valves yet? If not the valves have to be
used before they will seal correctly due to the hard steel ball and the softer brass body of the valve bedding in. I've been asked this many times and the valves have been ok when used. Dave
my reply->
I filled them. I pushed oil through them using an oil can at the spider hub... pushed until some oil came out but not too much.
They leaked so much I did not dare to use... I filled and tested twice with same result.
I have it off and can try a few more fill cycles. How many cycles do you think they need?
Thanks
Aftermarket UK Check Valve review
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Re: Aftermarket UK Check Valve review
Current registered, inspected, and running well 2 stroke motorcycles
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Re: Aftermarket UK Check Valve review
Seems to me, the ball should be seated during manufacture. Either that or a real teflon seat used. Counting on the ball to create it's own seat is pretty iiffy - especially with so little spring pressure. It's not like the ball hammers on the brass.
I was born with nothing and still have most of it left.
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Re: Aftermarket UK Check Valve review
Hi, Can anyone tell me which supplier in the UK they got their Check Valves from as I'm thinking of buying some for spares and I don't want to purchase a set of dud's. The only supplier I can find is in Dudley.
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Re: Aftermarket UK Check Valve review


Cheers,
Roger
GT750Battleship.
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Re: Aftermarket UK Check Valve review
Cheers Roger, I think I'll try a set and maybe try seating the ball in the valve myself with a light tap with a punch.GT750Battleship wrote:Hi,yes the Dudley UK connection is the only source that I know of for the check valves
on eBay UK
Cheers,
Roger
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Re: Aftermarket UK Check Valve review
When I asked how long before valves OK he said
a 10 mile ride will be ok
Dave
Well, my original lines are back on the GT750. They did not leak in a couple hour test but, think they do leak slowly.... after a couple weeks setting for example, it smokes first start but, had had much worse. It's not a good thing to leave leaking for I found that this extra oil as it burns (engine still cold and warms up) really sticks and cokes internals up.
All I can say is these aftermarket parts leaked very fast ahead of me attaching them. It is a bit time consuming to do job on GT750 and unless mine gets worse, I may not retry.
Maybe instead of SRIS valves i'll put straight fitting T these three together and make one drain plug to relieve crankcase of oil.
When I get the new Kawasaki check valves I'll test before I mount lines to engine and see if they leak or not
a 10 mile ride will be ok
Dave
Well, my original lines are back on the GT750. They did not leak in a couple hour test but, think they do leak slowly.... after a couple weeks setting for example, it smokes first start but, had had much worse. It's not a good thing to leave leaking for I found that this extra oil as it burns (engine still cold and warms up) really sticks and cokes internals up.
All I can say is these aftermarket parts leaked very fast ahead of me attaching them. It is a bit time consuming to do job on GT750 and unless mine gets worse, I may not retry.
Maybe instead of SRIS valves i'll put straight fitting T these three together and make one drain plug to relieve crankcase of oil.

When I get the new Kawasaki check valves I'll test before I mount lines to engine and see if they leak or not
Current registered, inspected, and running well 2 stroke motorcycles
74 GT250 (T350 upgrade),
76 GT250 (T350 upgrade),
71 T350,
70 T350,
74 GT380,
75 T500,
73 GT550,
75 GT750,
72 Yamaha DS7 (R5 upgrade),
77 Yamaha RD400 (Daytona Cyls),
73 Kawasaki H1 500
74 GT250 (T350 upgrade),
76 GT250 (T350 upgrade),
71 T350,
70 T350,
74 GT380,
75 T500,
73 GT550,
75 GT750,
72 Yamaha DS7 (R5 upgrade),
77 Yamaha RD400 (Daytona Cyls),
73 Kawasaki H1 500
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Re: Aftermarket UK Check Valve review
I just installed a set of the new aftermarket UK eBay oil injection check valves. Seemed to work when I pushed some compressed air through each, as you could hear the valve vibrating open in one direction only. I replaced all the banjo-style end pieces (5), except the silver one that has a check valve inline further up. Why did Suzuki do this for one line only, and can I just use another brass colored check valve there?
After all back together, I made a mark on the injection oil tank to see if any oil was seeping past the check valves and into the engine. Quick ride around the block, no smoking. Later to my dismay the oil had gone down a centimeter or more in the oil reservoir in just a week since last riding.
Looks like I have to go through the whole process again. Could the inline valve be leaking or one or more of the new ones?
This time I want to test each valve. How do you suggest I test the valves to see if they leak? I could just disconnect them at the end where the valves connect to the engine cylinders and crankcase and see if gravity alone allows the leak with a towel under each. Thanks.
After all back together, I made a mark on the injection oil tank to see if any oil was seeping past the check valves and into the engine. Quick ride around the block, no smoking. Later to my dismay the oil had gone down a centimeter or more in the oil reservoir in just a week since last riding.
Looks like I have to go through the whole process again. Could the inline valve be leaking or one or more of the new ones?
This time I want to test each valve. How do you suggest I test the valves to see if they leak? I could just disconnect them at the end where the valves connect to the engine cylinders and crankcase and see if gravity alone allows the leak with a towel under each. Thanks.
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Re: Aftermarket UK Check Valve review
You want to be careful using compressed air through check valves, to much pressure will ruin them.
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Re: Aftermarket UK Check Valve review
Thanks for the heads-up warning on the compressed air. Only used a can and not compressor, but will now avoid all together.
I will hang the whole oil harness of 6 lines after priming with oil and see which valves are leaking— of the (5) new aftermarket valves or the one inline valve not yet replaced. Anyone know where to get the inline check valve? Or, can I use another banjo check valve there if I can not find the inline check valve? There must be some reason they used an inline valve on that line.
I will hang the whole oil harness of 6 lines after priming with oil and see which valves are leaking— of the (5) new aftermarket valves or the one inline valve not yet replaced. Anyone know where to get the inline check valve? Or, can I use another banjo check valve there if I can not find the inline check valve? There must be some reason they used an inline valve on that line.