.61 two stroke=????? four stroke
04-28-2007, 12:05 AM
#2
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RE: .61 two stroke=????? four stroke
You'll get multiple opinions. Here's mine:
.40 two stroke = .60 four stroke
.60 two stroke = .90 four stroke
The power is different though
If I remember correctly, my .61 two stroke turns a 12x6 prop around 12500 rpm
My .91 four stroke turns a 14x6 prop around 9500 rpm
Comparing them side by side in ThrustHP it says both should be pulling around 10 pounds of static thrust. The high rpm two stroke generates a lot more prop noise than the four stroke.
.40 two stroke = .60 four stroke
.60 two stroke = .90 four stroke
The power is different though
If I remember correctly, my .61 two stroke turns a 12x6 prop around 12500 rpm
My .91 four stroke turns a 14x6 prop around 9500 rpm
Comparing them side by side in ThrustHP it says both should be pulling around 10 pounds of static thrust. The high rpm two stroke generates a lot more prop noise than the four stroke.
04-28-2007, 05:28 AM
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RE: .61 two stroke=????? four stroke
ORIGINAL: Groundskeeper3404
What size four stroke engine would be equivelant to a two stroke in the .60 range and also in the .40 range?
What size four stroke engine would be equivelant to a two stroke in the .60 range and also in the .40 range?
a 40 is probably about a 65 or so (saito..)
04-28-2007, 06:18 AM
#4
RE: .61 two stroke=????? four stroke
I`ve have a GB clipped wing Cub that I put a ST GS40 with Bisson Pitts muffler . I t did a nice job , but to have any power , I had to rev the heck out of it. That's what 2 strokes like.
I installed a Magnum 4s 52 on it. It does not have the high end rpms as the 2s but has a much better torque to rpm band.
A lot depends on what kind of plane your flying and what your flying style is going to be for that plane.
I installed a Magnum 4s 52 on it. It does not have the high end rpms as the 2s but has a much better torque to rpm band.
A lot depends on what kind of plane your flying and what your flying style is going to be for that plane.
04-28-2007, 08:31 AM
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RE: .61 two stroke=????? four stroke
I have been told to take a given two stroke size and then add half of it to get the same, or close to same, four stroke. So say a 60 size two stroke and then add half of it will make a 90 four stroke. I am sure this is not a fact, but more of a rule of thumb.
04-28-2007, 10:05 AM
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RE: .61 two stroke=????? four stroke
Thanks for the advise. I really like the sound of the four strokes. I,m building a Bridi Hobby-Kaos kit that I picked up at an auction. The instructions are not for the novice builder that I am, so I will most likely be using the beginner's forum for more advise. I was told that this plane will handle well in our Nebraska breeses.
04-28-2007, 08:38 PM
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RE: .61 two stroke=????? four stroke
I have a YS 63 on my 40 sized plane its works really good. It probably has more power than it really needs(but thats not a problem!!!
).
).
04-29-2007, 06:50 AM
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RE: .61 two stroke=????? four stroke
ORIGINAL: Groundskeeper3404
Thanks for the advise. I really like the sound of the four strokes. I,m building a Bridi Hobby-Kaos kit that I picked up at an auction. The instructions are not for the novice builder that I am, so I will most likely be using the beginner's forum for more advise. I was told that this plane will handle well in our Nebraska breeses.
Thanks for the advise. I really like the sound of the four strokes. I,m building a Bridi Hobby-Kaos kit that I picked up at an auction. The instructions are not for the novice builder that I am, so I will most likely be using the beginner's forum for more advise. I was told that this plane will handle well in our Nebraska breeses.
#1 4 Strokes are more expensive than 2 Strokes,
#2 4 Strokes are heavier,
#3 4 Strokes are a much more complicated engine (push rods and valves)
#4 Newbees should stay away from them for a while, because newbees tend to crash more than experianced fliers and the chances of hurting the 4 Stroke is higher than a 2 Stroke.
That having been said they are an excellent engine that can give you years of fun - but don't rush into them.
04-29-2007, 07:51 PM
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RE: .61 two stroke=????? four stroke
Yes bbbair, I now truly understand that fact and think that you give excellant advise. While trying my first attempt at landing, I perfomed a perfect three point landing in the top of the row of trees at the end of the airfield. I did land the plane, just not where I wanted to. Trainer plane-broke the tail pulling it out of the tree $20.00. Digital Servos, engine, battery and receiver-Recovered OK- $120.00. Being Embarassed in front of my friends and relatives-Priceless
Working on perfect, groundskeeper3404
Working on perfect, groundskeeper3404
04-29-2007, 08:23 PM
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RE: .61 two stroke=????? four stroke
Actually, I'd compare the weight of a saito four stroke to any comparible two stroke out there.
However, the rest of the statements are pretty much true....
However, the rest of the statements are pretty much true....
11-11-2007, 10:36 PM
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RE: .61 two stroke=????? four stroke
My YS .63 makes about the same power as a 60 size 2 stroke on 30% fuel. And it is much lighter than a 60 3 stroke. APC 13x4w at 11000+ rpm
11-12-2007, 01:33 AM
#12
RE: .61 two stroke=????? four stroke
ORIGINAL: Groundskeeper3404
Yes bbbair, I now truly understand that fact and think that you give excellant advise. While trying my first attempt at landing, I perfomed a perfect three point landing in the top of the row of trees at the end of the airfield. I did land the plane, just not where I wanted to. Trainer plane-broke the tail pulling it out of the tree $20.00. Digital Servos, engine, battery and receiver-Recovered OK- $120.00. Being Embarassed in front of my friends and relatives-Priceless
Working on perfect, groundskeeper3404
Yes bbbair, I now truly understand that fact and think that you give excellant advise. While trying my first attempt at landing, I perfomed a perfect three point landing in the top of the row of trees at the end of the airfield. I did land the plane, just not where I wanted to. Trainer plane-broke the tail pulling it out of the tree $20.00. Digital Servos, engine, battery and receiver-Recovered OK- $120.00. Being Embarassed in front of my friends and relatives-Priceless
Working on perfect, groundskeeper3404
Now that is funny right there. I dont care who you are that is funny
