22 hp 525 dollars

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nickec

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Finally. The people who make Predator Engines, those inexpensive models sold at Harbor Freight, are supplying a 670 cc v-twin.

22 hp 525 dollars.jpg image_25155.jpg

If only they had opted for the slightly smaller block which is used for 18 hp to 20 hp, or so.
Such a lighter engine is what Leeon Davis used in the DA-11.

I suspect that it is only a matter of time before someone, somewhere, puts this engine in a homebuilt. The price is just too tempting.

http://manuals.harborfreight.com/manuals/61000-61999/61614.pdf

http://www.harborfreight.com/22-hp-670cc-v-twin-horizontal-shaft-gas-engine-epa-61614.html
 

Dana

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100# heavier than the same HP 2-stroke, admittedly at 1/4 the price. Though with all the reputation of 2-strokes as being unreliable, I'm not sure a Harbor Freight engine will be any better...

Dana
 

Hot Wings

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I suspect that it is only a matter of time before someone, somewhere, puts this engine in a homebuilt.
My HF store doesn't yet stock them. Apparently they have been available in some of the west coast stores for quite a while.

Predator 670cc v twin - YouTube

One of the downsides of these clones is that they only have a 1 inch output shaft rather than the more common 1 1/8". If you could forward a code that would let me get the discount shown I'd order one to examine.

Edit: The number shown in the photo works! It's on the way. If it turns out to be less than expected it will go on a little air boat.

--------------
125 lbs....

This is shipping weight. It's basically a clone of the Honda GX 620 and stripped down it should be comparable in weight to the B+S as used in the MC 30.
 
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nickec

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... If you could forward a code that would let me get the discount shown I'd order one to examine.

Edit: The number shown in the photo works! It's on the way. If it turns out to be less than expected it will go on a little air boat.

... It's basically a clone of the Honda GX 620 and stripped down it should be comparable in weight to the B+S as used in the MC 30.
I agree. I think there is a reasonable probability that it will work well. Good to hear you saw the code. That was my intent.

I considered posting to a Powered Parachute forum. They are likely on the job already. ;)
 

Hot Wings

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Good to hear you saw the code. That was my intent.
I'd probably have ordered one any way but I though it best to get it while the code still worked. $175 saved will pay for a bunch of little parts. Thanks for the post!!

My plan is to break the engine in on a test stand and then measure the torque, fuel consumption and a base line on the various engine parameters. After that tear it down, measure everything, and reassemble with a conversion for a prop in mind. I'll report back on what I discover.

$558.23 with shipping and tax.
 

nickec

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... My plan is to break the engine in on a test stand and then measure the torque, fuel consumption and a base line on the various engine parameters. After that tear it down, measure everything, and reassemble with a conversion for a prop in mind. I'll report back on what I discover.

$558.23 with shipping and tax.
It should prove very, very interesting. Thanks for sharing.
 

cluttonfred

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Something like this might work very well in a minimalist "fat ultralight"/microlight designed to carry the weight. Something inspired by Mike Sandlin's Bloop but scaled up to about 300 lbs empy weight would be good fun especially with a little fuselage pod like a WWI pusher.

2014-01-20 Otay.jpg + cf05_dh2-2_0.screensize.jpg = ?

I still think it would be great if someone could develop a bolt-on prop hub for these small V-twin engines to take the prop-related stresses off the engine and allow for pusher or tractor conversions with very little effort. Maybe just a spool-shaped prop hub with a keyway to slip over the shaft and ball bearing races on both sides of the bottom, sandwiched between two circular plates with the other halves of the ball-bearing races and a spacer? Some sort of torsional damping would be great but with light wooden props might not be essential. If the shaft size and attachment bolt pattern were based on standard small-engine specs the the prop hub could easily be used on a range of engine sizes from different manufacturers and switched from one engine to another. Something like this...

prop hub.jpg
 
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litespeed

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Something like this might work very well in a minimalist "fat ultralight"/microlight designed to carry the weight. Something inspired by Mike Sandlin's Bloop but scaled up to about 300 lbs empy weight would be good fun especially with a little fuselage pod like a WWI pusher.

View attachment 35971 + View attachment 35972 = ?
That is just what I was thinking- great minds.........

A Airdrome DH-2.....cool fun.
http://www.airdromeaeroplanes.com/airdrome/images/dh2 a.JPG

And a few mods and hopefully motor can be just like this.......... https://www.youtube.com/watch?v=BZ0IYnGNfH8

88lbs approx hp ? and 5 litres a hour cruise. Sounds great but 88lbs is with starter and full exhaust, builder says he has over 113 hrs on engine and 4 flights.

Sounds like a good combo.
 

litespeed

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Given these are so cheap, you can be looking at a fully modded, redrived engine with prop under $2,000. For the miserly builder.

A Ace redrive is nice and cheap at $ 590 US ex India. Leaves plenty to play- better carb, nice rods, higher compression pistons and cam. Lots of cheap go fast goodies available now.

http://www.aceaviation.co.uk/index_files/Page456.htm

The issue of the smaller shaft could be a issue though.

Litespeed
 

cluttonfred

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Wow, that does look like a good deal. Does anyone have any experience with the Ace redrives? If something like that would be suitable for a 28-30 hp, fuel injected Subaru Robin EH72 then it might be perfect for my single seat design project.
 

Hot Wings

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I still think it would be great if someone could develop a bolt-on prop hub for these small V-twin engines to take the prop-related stresses off the engine and allow for pusher or tractor conversions with very little effort.
Adding a prop is probably not going to be the hardest part of the conversion. Lots of other little things, like what to do with the stock governor, might prove to take more time and thought. Even the tractor/pusher decision makes a difference. These little engines are designed to have the cooling air flow through in one direction - intake to exhaust - and trying to change that flow direction may mean less than ideal cooling patterns.

I have 2 projects that this conversion might work on. One is a tractor, the other a pusher. The tractor requires direct drive, the pusher could benefit from using a PSRU but I'm hoping it won't be needed. It may turn out that it is best to develop a direct drive prop attach for both ends to accommodate cooling air flow requirements. Off the shelf PSRU's are available for the PTO end but I've seen none that are ready to bolt onto the flywheel end after removing the flywheel - so we are pretty much stuck with having to deal with the cooling flow reversal if using a PSRU as a tractor. Valley engineering seems to be able to make it work for their conversion so it may not be the problem I fear it could be.
 

cluttonfred

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You make some good points, Hot Wings, though I don't think that direction of cooling air flow is going to be as critical as all that. If it were, you could always use plenum chambers or a pressure cowling with a rear inlet and a front outlet.

I received a prompt and helpful reply from Ace Aviation about their redrives, they certainly look nice and the price can't be beat. Stay tuned....
 

Hot Wings

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Next on the order list is a prop for testing. It must be variable pitch. So far the short list includes Ivo, Warp, and Powerfin. I have no real world experience with any so I am open to hearing others opinions.

Facts offered will be considered suspect :gig: :ban:
 

Dana

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I had good results with a GSC ground adjustable prop (48" two blade) on my paramotor project.

Dana
 

Jan Olieslagers

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Hot Wings

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I had good results with a GSC ground adjustable prop (48" two blade) on my paramotor project.

Dana
I'd forgotten about them. I like the fact that they are wood based. It looks like they are cheaper too, but at this point cheap is not the primary factor.
 

Victor Bravo

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Uhhh, guys... sorry to be a party-pooper, but if any of you have ever actually experienced a forced landing in an airplane, you might want to re-think the low cost of a rock-bottom Chinese clone engine.

Start with the money you saved on the engine. Celebrate the savings, and walk away grinning madly over how much money you saved. Then add the cost of repairing the bent landing gear, the bent fuselage, the bent wing struts, the increase in your insurance, and finally the cost of the medical bills from the broken legs. Make one column to calculate only breaking one leg,a nd another column to address if both legs are broken.

To be fair, let's say the ambulance ride and the EMT was covered by your health insurance. Let's also say that the damage to the house you landed on was mostly covered by their homeowner's insurance, but they will likely ask you for the deductible. So make two columns for this point... one with their deductible and one without.

Don't forget to add some factor for the month of work you will be missing while laid up in the hospital. Make a calculation for the differential financial coefficient comparing the income you get from your disability insurance versus the actual lost wages. This will vary from one job to another.

When you have filled in allt hese columns, make a direct comparison as to whether you would have been better off with a Subaru / Generac / Honda or the Twice Cooked Engine.

Now, let's take a moment to consider the experiences some of us have had with Harbor Freight products. Most of us know that there are certain things you can buy there and get a good result, and some things you should not buy there because you will likely be returning it. Hammers, anvils, and open end wrenches (the ones that cost more than 25 cents each) are usually no problem. Electronics, precision lathes, precision metal working equipment, and tools that have hardened or tempered components are usually mistakes you make only once at HF.

Now which category do you think "airplane engine" would likely be in?
 

Hot Wings

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Uhhh, guys... sorry to be a party-pooper,
All of what you say is true, but it also presumes that the stereotype of poor quality HF products applies in this case. It may in fact turn out that it does. I'm willing to gamble the $'s (but not the body*) to find out for myself. I've direct experience with 3 HF clone engines and have watched a few owned by others. In all cases they have proven to be of at least the same quality as the Briggs, Honda, or Tecumseh they replaced. Just as expensive doesn't always guarantee good quality cheap doesn't 100% equate with junk.

Besides, what I learn is likely to be directly transferable to a genuine Honda if the HF isn't of consistent quality.

*I plan to personally test to ASTM F2339 presuming a 500 hour TBO before I even think of flying out of range of a suitable landing site.
 
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