Honda GX25 OHC, NEW (WITH PICS )
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RE: Honda GX25 OHC
ORIGINAL: aero nut
a couple of questions? how much did you pay for that engine? and are they readily available?
a couple of questions? how much did you pay for that engine? and are they readily available?
[link=http://www.smallenginewarehouse.com/ProductList.asp?Category=Engine&Supplier=Honda]http://www.smallenginewarehouse.com/ProductList.asp?Category=Engine&Supplier=Honda[/link] and received it the very next day (one state away)
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RE: Honda GX25 OHC
[quote]ORIGINAL: BBriBro
I'm still in search for the "perfect" carb for the Honda. the bad news is I drilled out the main jet and actually lost rpm on top. the good news is there is a Low end adjustment !!! It is down inside the throttle barrel. I talked to a Walbro tech, he said to dig out the epoxy filling with an x-acto and there might be a mixture screw. Well I dug and dug, untill I hit metal under the epoxy. Some friends looked at it, and we all thought, nah, no screw in there. Then I got to thinking, and I couldn't imagine why they would bother to put epoxy in there unless they were trying to prevent tampering, so I starting drilling down in there, with brass shavings flying everywhere. I was either going to find a mixture screw, or drill clean through the entire carb searching for one. I ended up using a tiny cutter on my dremel, and would you believe, there is a screw in there. They dropped a brass plug in there first, then filled it with epoxy, it was a major PITA. The motor is still apart, so I haven't tried to adjust the idle mixture, But I did the same mod to my Honda weedeater, (the one I really use on the grass) and it starts much easier, idles slower, accelerates without stumbling, does't die when cold, even at idle, I can't wait to run the conversion. I think with a new main jet (maybe an assortment of sizes) the stock carb will be fine. The one on the GX25 has an accelerator pump, my weedeater doesn't so it should be even better on the transition.
ORIGINAL: captinjohn
The brass screw in the center of the rotating barrel (throttle) is the mix adjustment I think.
The brass screw in the center of the rotating barrel (throttle) is the mix adjustment I think.
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RE: Honda GX25 OHC
ORIGINAL: Antique
Now that you've got us this far don't leave us hang'n !!! How about an update on the project ???
Now that you've got us this far don't leave us hang'n !!! How about an update on the project ???
#30
RE: Honda GX25 OHC
I was positive there was a mix screw...but I fogot to say it may be hidden by a filler above it to hide it fom us tinkering type of RCer,s!!!! Can you send your photos in a smaller size? Us poor folks have slow servers...ect .....making it a very long process to see the photos at all. Thanks Capt,n
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RE: Honda GX25 OHC
ORIGINAL: captinjohn
Can you send your photos in a smaller size? Us poor folks have slow servers...ect .....making it a very long process to see the photos at all. Thanks Capt,n
Can you send your photos in a smaller size? Us poor folks have slow servers...ect .....making it a very long process to see the photos at all. Thanks Capt,n
#32
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RE: Honda GX25 OHC
Please keep us posted on your progress. I'd also like to know when you run the other bigger Honda four-stroke you have; (the 31).
I have this vision I just can't get out of my mind. A big, (like 96" wingspan), old timey looking model with a four-stroke for the neat sound. I'm thinking an old Antoinette look alike, or something along those lines. Something majestic and relaxing to fly. I'll probably have to sit down and design it, 'cause I just can't get the idea out of my head. I'm looking forward to hearing how your experiments with these engines and the plane you are building turn out.
Thanks,
AV8TOR
I have this vision I just can't get out of my mind. A big, (like 96" wingspan), old timey looking model with a four-stroke for the neat sound. I'm thinking an old Antoinette look alike, or something along those lines. Something majestic and relaxing to fly. I'll probably have to sit down and design it, 'cause I just can't get the idea out of my head. I'm looking forward to hearing how your experiments with these engines and the plane you are building turn out.
Thanks,
AV8TOR
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RE: Honda GX25 OHC
The Big Bee is almost finished. I am having a custom landing gear made from TNT, so I don't have to use the old fashioned heavy 1/4" wires it came with. I ordered a WYK-61 and a WYK-16 carb to try on the GX25. The stock WYB (fixed jet) carb is 8mm, the WYK-61 is 9 mm (with hi and low speed needles) and the WYK-16 is 10.5 mm (also with both needles, and no primer, so hopefully it will be smaller, lighter and more compact) I am expecting all of the above parts this week, So hopefully I can get it in the air by this weekend.
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RE: Honda GX25 OHC
ORIGINAL: RCIGN1
All WYK carbs are the same physical size [8D]
All WYK carbs are the same physical size [8D]
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RE: Honda GX25 OHC
BBB,
Next time you have your Honda 25 out, would you mind removing the flywheel, coil, muffler, and anything not needed to do an CDI conversion and weighing the thing. If it's semi-light I'd like to buy one. Thanks for all the pics and details.
Doug
Next time you have your Honda 25 out, would you mind removing the flywheel, coil, muffler, and anything not needed to do an CDI conversion and weighing the thing. If it's semi-light I'd like to buy one. Thanks for all the pics and details.
Doug
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RE: Honda GX25 OHC
ORIGINAL: DougT
BBB,
Next time you have your Honda 25 out, would you mind removing the flywheel, coil, muffler, and anything not needed to do an CDI conversion and weighing the thing. If it's semi-light I'd like to buy one. Thanks for all the pics and details.
Doug
BBB,
Next time you have your Honda 25 out, would you mind removing the flywheel, coil, muffler, and anything not needed to do an CDI conversion and weighing the thing. If it's semi-light I'd like to buy one. Thanks for all the pics and details.
Doug
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RE: Honda GX25 OHC
OK, I ordered one..I will convert it to my ignition, lighten as much as possible, find a carb that works, test it with different props...It will be for sale for $325 later if anyone wants it, otherwise it will be on one of my planes..Something LIGHT....
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RE: Honda GX25 OHC
This seems to be a hot topic, so I just removed the engine, and all it's accessories, I have some weights for each component. My notes were mostly chicken scratch and getting hard to read, so I started over, with every part, on a digital postal type scale.
Bare engine (No carb, no spark plug, no ignition, no flywheel, no muffler, no mount, no hub) 43.3 oz
Spark Plug, ( I read that the shorter plugs are lighter, so here is the stock one just for comparison) .8 oz
Coil (with mounting screws) 4.0 oz
Flywheel (after grinding) 8.8 oz
Carr Precision Hub with washer and prop bolt 3.0 oz
Carr Precision mount with 3 flat head screws 3.4 oz
Stock Honda Muffler 3.2 oz
My custom exhaust pipe 1.0 oz
Stock Carb (WYB 6B) 3.9 oz
New Carb (WYK 61) 4.1 oz
If you add it up the individual parts that comes to 68.4 oz. My engine put together , firewall ready, on the scale as one piece read 68.6 oz. So that should answer most questions
Bare engine (No carb, no spark plug, no ignition, no flywheel, no muffler, no mount, no hub) 43.3 oz
Spark Plug, ( I read that the shorter plugs are lighter, so here is the stock one just for comparison) .8 oz
Coil (with mounting screws) 4.0 oz
Flywheel (after grinding) 8.8 oz
Carr Precision Hub with washer and prop bolt 3.0 oz
Carr Precision mount with 3 flat head screws 3.4 oz
Stock Honda Muffler 3.2 oz
My custom exhaust pipe 1.0 oz
Stock Carb (WYB 6B) 3.9 oz
New Carb (WYK 61) 4.1 oz
If you add it up the individual parts that comes to 68.4 oz. My engine put together , firewall ready, on the scale as one piece read 68.6 oz. So that should answer most questions
#41
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RE: Honda GX25 OHC
I converted and used a GX31, which is the same engine only larger, on a Giant Eindekker. It worked ok, though a bit underpowered for that plane.
It can be run inverted, but it's problematic. The oil slowly runs down and collects on the spark plug. I used to take the plug out and stick a piece of paper towel in the hole. Then remember to turn the airplane over and check the oil when you want to run it. Upright should be no problem.
Without the airfilter and with a free flowing muffler or straight stack, expect to have problems getting the carb to go rich enough. If you do a carb swap, do some research here in the forum and find a WYK barrel style carb with dual adjustment needles to replace yours.
But the sound is really cool, and it will barely "sip" gasoline.....
AV8TOR
It can be run inverted, but it's problematic. The oil slowly runs down and collects on the spark plug. I used to take the plug out and stick a piece of paper towel in the hole. Then remember to turn the airplane over and check the oil when you want to run it. Upright should be no problem.
Without the airfilter and with a free flowing muffler or straight stack, expect to have problems getting the carb to go rich enough. If you do a carb swap, do some research here in the forum and find a WYK barrel style carb with dual adjustment needles to replace yours.
But the sound is really cool, and it will barely "sip" gasoline.....
AV8TOR