I killed my old ryobi...kind of.

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dboyd351

dboyd351

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Well....... You got me thinking about that and I was going to post a reply to your message, but I'll just port it here. The carbs on these are little, like 24/64". That's because much of the air flows through the air valve, not the carb. But the 28/64" carbs are not that much bigger, and I was just contemplating giving it a try on a ported 40cc one I've been playing with. So I agree it might be worth the experiment. I have some carbs I can swap the shafts on.

Chris,
Let me know if you try it and what the results are. I'd prefer the venturis be the same, too, but considering the new Ryobi carb was $65 last time I looked, it's worth a try on a $13 replacement. I'll probably try it at some point, too.
David
 

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f969fee500302bcafc767cad28b194364d2270a49557d058968690359d17ec89.jpg


I took the carburetor apart again and it was just a little shmotz blocking the impulse port!!



The jumpy video is because of a wet screen on my phone, everything was wet:laugh:
 
Chris-PA

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dboyd351

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Chris,
This probably should have been obvious, but I just thought of something. If that chinese carb is designed to work with the Earthquake, which is a non strato clone of the GZ4000/Ryobi 10532, then I wonder how the carb would work on a Ryobi if you didn't connect it to activate the strato valve? You would essentially be turning the Ryobi back into a GZ3800 non strato saw. Might be really easy, solve the question about differing venturi sizes and fix the carb problem. I might just try it.
 

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It will bolt right in, I did it awhile back.
The ryobi ry3714 is based on the ry10532/3540, it isn't stratocharged and has the same design carb as the earthquake.
 
Chris-PA

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Chris,
This probably should have been obvious, but I just thought of something. If that chinese carb is designed to work with the Earthquake, which is a non strato clone of the GZ4000/Ryobi 10532, then I wonder how the carb would work on a Ryobi if you didn't connect it to activate the strato valve? You would essentially be turning the Ryobi back into a GZ3800 non strato saw. Might be really easy, solve the question about differing venturi sizes and fix the carb problem. I might just try it.
Look at the MCulloch XM40 saws, or the Partner 350S - these are copies of the Zenoah G3200 chassis, but use the 35 or 40cc strato cylinders with the strato ports blocked off. They put a 28/64" carb on it feeding the conventional intake. I never ran one, but they have to be at a serious disadvantage giving up all the strato intake port area.

Keep in mind that performance is about increasing the air volume - there is never any problem getting enough fuel in, as even a tiny carb to flow enough air for all the fuel you could possibly need.

I have been re-thinking the carb size on these and I doubt going from 24/64" to 28/64" would be a problem. My 40cc 142 came stock with a 34/64" carb and while it runs great it does not turn the rpms I'm getting out of the GZ4000-based saws, but the large carb still meters fuel just fine. So I expect the slightly larger carb would be OK.

This weekend I should get a chance to try out my ported GZ4000 clone with the modified air valve - if it can pull the rpms the Ryobi does then I won't put the bigger carb on. If it can't I will either get a real Zenoah air valve or look at the larger carb - but if I go with the larger carb I may go back in and increase the conventional intake duration to take better advantage of it.
 
nenicu

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I'v had a Zenoah clone with strato cylinder and non strato piston. It revs better than G3800 clones.I now have a strato clone with blank strato ports. It has a normal carb and works OK. The other one with a bigger carb[13 mm venturi] was the bomb.[the piston is 2/3 the weight of the strato piston]. So you can run the strato saw with a normal carb but you loose some power.
 
nenicu

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For ''dboyd351'': the G3800 has a totaly diferent piston and cylinder. The strato piston on the 40 cc is double the weight of the normal piston and the cylinder is a lot more complicated. You can use it non strato but the weight of the piston makes the diference.
 
dboyd351

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For ''dboyd351'': the G3800 has a totaly diferent piston and cylinder. The strato piston on the 40 cc is double the weight of the normal piston and the cylinder is a lot more complicated. You can use it non strato but the weight of the piston makes the diference.
I'm not trying to swap out the cylinder and piston, just looking to replace a defective/troublesome carb for substantially less than the asking price for a new OEM carb. I realize I'd probably give up some of the quick, high revving of the strato design, but they say the Earthquakes run pretty well so I thought it might be a worthwhile tradeoff.
 
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I'v had a Zenoah clone with strato cylinder and non strato piston. It revs better than G3800 clones.
Even with the strato ports blocked off it's still a very nice quad closed transfer cylinder. It's just that given everything else the same it's going to work better with the increased intake area from the strato intake.
 
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I'm not trying to swap out the cylinder and piston, just looking to replace a defective/troublesome carb for substantially less than the asking price for a new OEM carb. I realize I'd probably give up some of the quick, high revving of the strato design, but they say the Earthquakes run pretty well so I thought it might be a worthwhile tradeoff.
I guess swapping the shafts might be problematic there, as the GZ400/4000 use a ZAMA C1Q carb and the Chinese carbs are probably Walbro WT copies.

The Jenn Feng "McCulloch" GZ4000 clones like my MS4018 used a Walbro WT750, which is what I used to swap the shafts with the strato linkage over to the WT391. Those are fairly rare beasts though.
 

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Last time I cut I decided it was better to cut, pile, burn, and pick some for firewood. Some of it is good enough to mill but it's just to much effort for the what you would get. Big Stacks of logs are sitting on road by us waiting to be picked up by the new processor company near the old auberry lumber mill.
 

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Got another ry10532 in the mail from ebay today for 45$ just needed a carb tune and worm gear which I had from my other one. This one looks like a very low use saw.
 

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The old ryobi got a side by side run against the husqvarna 445 today with fresh sharp on the chains and the 445 was 2-3 seconds slower if the chain didn't stop. The beating was so bad it didn't start for the third cut i was going to make.
 
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