Duromax has a slightly higher (Than the Honda and the Predator clones) displacement engine http://www.generatorfactoryoutlet.com/products/duromax-xp23hpe-713cc-23-hp-v-twin-engine-w-electric-start-key-switch-box
$200 more than the HF Predator.
Red Beard Garage is working on it http://www.youtube.com/watch?v=oSBTmVB8pQA. He thinks it will run up to 4000 RPM without touching anything but the governor. The usual aftermarket cams, rockers, etc, are presumed to fit on on it. Performance 670
advertised dry weight is 113 lbs. Ditching the plastic shroud, the governor, the flywheel, muffler, should shave at least 30 lbs off this. Losing the flywheel might mean losing the starter, unless you want to custom build a low inertia mount for the ring gear, so that might scrape as much as another 24 lbs off. Adding back an Ace Aviation reduction drive adds about 9 lbs
So running it up to 5000 RPM might yield 40 HP, prop speed with the standard ratio would be 2777 rpm, so a long prop could be swung. MIGHT be as light as 70 lbs for a hand prop setup, less exhaust, prop and mounts.
Comparison: Cuyuna 430 advertised 65 lb and 30 hp at 5500 rpm, reduction ratio was typically 3 to 1. Rotax 447 dual carb = 59 lb and 40 hp at 6800 rpm (b-box ratio 2.24 to 1 so prop speed would be 3035). 1/2 VW, about 90 lbs, up to 45 hp?
Rough cost: Bare DuroMax 713 engine $999. Mikuni Carb kit $379.50 Air filter $29.95 506 cam $299.99 Billet rod $199.99 HD valve springs $29.99 HD push rods $49.99 Crank Trigger ignition $199 fancy coil $179 Ace Redrive shipped to the US $800. $3,166.41 so far.
Price comparison with Scott Casler 1/2 VW: 32 HP hand start = $3150. 45 HP hand start $4650.
I'm beginning to think this is a viable choice for small light airplanes. Affordaplane, Circa Dream Classic, Kolb Ultrastar, Skylite, Team Mini- or Hi-Max, possibly the Graham Lee Miranda I just bought plans for.
Others have noted this class of engines (Hot Rod Honda Clones) seems to have NO fixed wing flying examples. It's not clear if Armilite has actually flown a V-twin, although I haven't reviewed all his posts.
$200 more than the HF Predator.
Red Beard Garage is working on it http://www.youtube.com/watch?v=oSBTmVB8pQA. He thinks it will run up to 4000 RPM without touching anything but the governor. The usual aftermarket cams, rockers, etc, are presumed to fit on on it. Performance 670
advertised dry weight is 113 lbs. Ditching the plastic shroud, the governor, the flywheel, muffler, should shave at least 30 lbs off this. Losing the flywheel might mean losing the starter, unless you want to custom build a low inertia mount for the ring gear, so that might scrape as much as another 24 lbs off. Adding back an Ace Aviation reduction drive adds about 9 lbs
So running it up to 5000 RPM might yield 40 HP, prop speed with the standard ratio would be 2777 rpm, so a long prop could be swung. MIGHT be as light as 70 lbs for a hand prop setup, less exhaust, prop and mounts.
Comparison: Cuyuna 430 advertised 65 lb and 30 hp at 5500 rpm, reduction ratio was typically 3 to 1. Rotax 447 dual carb = 59 lb and 40 hp at 6800 rpm (b-box ratio 2.24 to 1 so prop speed would be 3035). 1/2 VW, about 90 lbs, up to 45 hp?
Rough cost: Bare DuroMax 713 engine $999. Mikuni Carb kit $379.50 Air filter $29.95 506 cam $299.99 Billet rod $199.99 HD valve springs $29.99 HD push rods $49.99 Crank Trigger ignition $199 fancy coil $179 Ace Redrive shipped to the US $800. $3,166.41 so far.
Price comparison with Scott Casler 1/2 VW: 32 HP hand start = $3150. 45 HP hand start $4650.
Hirth 2702 Fan cooled Recoil Start | | $4445.00 |
Belt reduction drive | | $1062.00 |
I'm beginning to think this is a viable choice for small light airplanes. Affordaplane, Circa Dream Classic, Kolb Ultrastar, Skylite, Team Mini- or Hi-Max, possibly the Graham Lee Miranda I just bought plans for.
Others have noted this class of engines (Hot Rod Honda Clones) seems to have NO fixed wing flying examples. It's not clear if Armilite has actually flown a V-twin, although I haven't reviewed all his posts.
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