important Siris system valves

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salvatore
Posts: 110
Joined: Fri Nov 09, 2018 1:28 am

important Siris system valves

Post by salvatore »

a valve of the siris system of my 380 L has broken, I can eliminate this system, what are the problems without? I have read that Suzuki has eliminated this system from the series after the 1974 I ask you for help. thank you
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barney01
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Joined: Wed Sep 26, 2012 7:33 pm
Location: Prestatyn.Wales

Re: important Siris system valves

Post by barney01 »

Hi
The SRIS system is there to prevent heavy smoke emissions and is not necessary to the running of the motor . The idea is any unused oil which collects in the bottom of the crankcase is fed through the non-return valve and into the upper cylinder where it's burnt during combustion. It was purely done by SuzukI to satisfy the authorities over pollution omissions.
Many owners just fit a bolt and gasket washer in the place of the valve and seal the inlet pipe on the cylinder with glue.
NO SMOKE .......NO POKE
barney01
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Location: Prestatyn.Wales

Re: important Siris system valves

Post by barney01 »

Of course if you want your bike to be all original
.https://www.discountbikespares.co.uk/?s ... pe=product
NO SMOKE .......NO POKE
salvatore
Posts: 110
Joined: Fri Nov 09, 2018 1:28 am

Re: important Siris system valves

Post by salvatore »

I understand, but if I delete this system I will have more smoke coming out of the drains? I would be to eliminate but I drive the bike in the city I am afraid that the smoke is excessive, your advice of great help on what to do.
barney01
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Joined: Wed Sep 26, 2012 7:33 pm
Location: Prestatyn.Wales

Re: important Siris system valves

Post by barney01 »

It really depends on the oil you use. Modern 2 stroke oil smokes a lot less than it did back on 1970. If you ride in the City a lot I would replace the valve if you only ride there occasionally it won't make much difference without the valves.
NO SMOKE .......NO POKE
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EvansWard
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Location: Macon GA USA

Re: important Siris system valves

Post by EvansWard »

Suzuki didn’t eliminate the SRIS system on the GT750 after 1974 as my 76 GT750A has it. I did try to use the factory slip clips (new) but couldn’t get them to even come close to fitting so went with black zip ties.
1976 Suzuki GT750
1972 Kawasaki H2 750 Mach IV
1984 Yamaha RZ350
barney01
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Joined: Wed Sep 26, 2012 7:33 pm
Location: Prestatyn.Wales

Re: important Siris system valves

Post by barney01 »

SRIS was only discontinued on the GT380
NO SMOKE .......NO POKE
teazer
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Location: Chicago

Re: important Siris system valves

Post by teazer »

The bike pumps the same amount of oil - SRIS or no SRIS. The difference in theory is that if one cylinder has surplus oil, then it will be shared with another cylinder so that all will smoke similarly rather than one smoking more than the others. Use a modern oil and you will have less smoke than a stock bike.

Some of us automatically blank off the SRIS on our bikes because valves leak and if it smokes too much on one side, it's time to clean out the oil supply check valves or fit a 3 into one exhaust. Easiest cure is to ride harder and burn off any surplus oil.
salvatore
Posts: 110
Joined: Fri Nov 09, 2018 1:28 am

Re: important Siris system valves

Post by salvatore »

I understand, I think to eliminate the system, I redid the engine with new pistons, I checked the oil pump valves are free without losses, I will use oil bardahl KGR limiting the maximum pump, this when I will have traveled about 1000 km, now I ask is right that I at the first ignition of the new engine I use a petrol with a 2% of oil per liter, even if the pump does not work well I protect the engine. You advise me to be right.
I also tried to rotate the oil pump using a 14 wrench on the left side rotor, but by hand the revs were weak to see the oil come out of the valves, my idea is possible. Sorry if I'm not clear to explain but I use the translator, forgive my language. Thank you
barney01
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Joined: Wed Sep 26, 2012 7:33 pm
Location: Prestatyn.Wales

Re: important Siris system valves

Post by barney01 »

Firstly you can put oil in the petrol for first start up a lot of people do that to make sure the engine is protected. I think you are far better to put a little oil in each spark plug hole is far better practice. Oil in the petrol will not lubricate the crankshaft just the cylinders thats why there is an oil pump.The Suzuki oil pump is very robust and very rarely fail. It is not possible to get oil to pump using a manual wrench. Be very careful not to damage the pump by forcing it. Remember the pump arm only returns to off after several rotations of the crankshaft and any attempt to force it back manually will damage the pump. If you are worried about the pump working you can do 2 things to check. First way is to fill the oil lines with different coloured oil so you will see the oil moving down the lines when the engine starts OR you can loosen a banjo where the oil line meets the engine and start the motor. Oil should escape around the banjo.
NO SMOKE .......NO POKE
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