petetheprinta Posted October 28, 2012 Share Posted October 28, 2012 Bolly (the prop people) are bringing out a kit aircraft with a Harley air cooled 90hp 4 stroke V Twin (120hp option) engine. Specs are :- MT weight 295 kg. MTOW 600 kg Length 6650mm Wing span 11.05m Cabin width 1260mm 115kts full power cruise Over 100kts economy cruise Fuel burn 15ltrs/hr @ 90kts Fuel capacity 175 litres again 175 litres Endurance 11 hrs Stall clean below 45kts Stall landing config below :38 kts Payload inc. fuel 305kg Factory assembly commences Jan 2013 Sky Blazer kit will include. Complete airframe all aluminium f/glass and CF construction Engine Prop Bolly 72" 2 blade ground adjustable with spinner Complete wiring loom landing lights full digital instruments VHF transceiver, headsets Dual control with elevator trim GA style yoke Tricycle undercarriage castor nose wheel Folding wings Estimated price $49,650 + battery and paint Approx $60,000 with build assist Sounds like a bargain... www.skyblazeraircraft.com Harley engine...yum, lots and lots of trick options and the sound......potato potato potato. Link to comment Share on other sites More sharing options...
fly_tornado Posted October 28, 2012 Share Posted October 28, 2012 a harley? Link to comment Share on other sites More sharing options...
petetheprinta Posted October 28, 2012 Author Share Posted October 28, 2012 a harley? From their web sight "The engine selected for our Prototype Sky Blazer is a 96 cubic inch v-twin with balance shafts Based on the Harley Davidson Twin Cam 96B engine. This engine will have some modifications to suit aviation" Seen the engine, pretty well straight HD main difference seems to be engine is balanced to try and eliminate vibrations, different output obviously to accommodate reduction drive. Link to comment Share on other sites More sharing options...
Steve L Posted October 28, 2012 Share Posted October 28, 2012 slow revving, light, powerful and the twin cams are very reliable.... this has been argued before but im still all for it. there was a manufacturer in the states doing just this who posted a video, sounded better than a radial. cant remember the name though Link to comment Share on other sites More sharing options...
damkia Posted October 28, 2012 Share Posted October 28, 2012 Ahhh, HD V twins... Don't so much "idle", as "fail to stall". I would be interested to see how they go about balancing a very unbalanced engine, then try to get a roughly equal torque output from the shaft. It's going to play hell with any props on the front, even with a PSRU. I would have thought taking the cylinders and heads and machining up a new bottom end for them would have been a good start. 1 Link to comment Share on other sites More sharing options...
winsor68 Posted October 28, 2012 Share Posted October 28, 2012 You can stop a Harley engine from Shaking? Link to comment Share on other sites More sharing options...
petetheprinta Posted October 28, 2012 Author Share Posted October 28, 2012 I have always thought the Harley Twin Cam would make a good engine for an LSA. Having had Harley's for many many years the motors have just got better and better. Far more reliable, plenty of torque, the Twin Cams particularly are easy to work on and service. Parts are easy to come by and not at a ridiculous price. Air cooled comparatively light at about 60-80kgs depending on config. The 96B of course goes a long way to dampening down vibration with its chain driven counter balances. Balance the flywheels and you have a vibration free motor (just about). They will be rubber mounting the motor in the Sky Blazer and voila. Can't wait to see one. Gimme gimme gimme. 1 Link to comment Share on other sites More sharing options...
petetheprinta Posted October 28, 2012 Author Share Posted October 28, 2012 You can stop a Harley engine from Shaking? You can indeed my custom SoftTail has a balanced and blueprinted 110ci and you could stand a 10c piece upright on it when it's running. Well..a 50c piece. 1 Link to comment Share on other sites More sharing options...
skyfox1 Posted October 28, 2012 Share Posted October 28, 2012 You can stop a Harley engine from Shaking? Yes turn the key to off. 2 Link to comment Share on other sites More sharing options...
fly_tornado Posted October 28, 2012 Share Posted October 28, 2012 A couple of years ago I had an Ebay alert, you know those daily emails you get when you click save search in ebay, for a PSRU turn up an item for auction, 1x low hour PSRU to suit harley V-twin good condition, clicked through on the sellers other items and he was also auctioning an entire S&S engine in pieces apart from the block and a conrod... Link to comment Share on other sites More sharing options...
fly_tornado Posted October 28, 2012 Share Posted October 28, 2012 Link to comment Share on other sites More sharing options...
fly_tornado Posted October 28, 2012 Share Posted October 28, 2012 According to the designs I have seen, for it too be reliable it would need a rubber isolator ring and or a clutch to stop the engine destroying the belt and prop, direct drive setups don't last very long... Link to comment Share on other sites More sharing options...
Guest Howard Hughes Posted October 28, 2012 Share Posted October 28, 2012 Looks like 2/7ths of a radial engine! Link to comment Share on other sites More sharing options...
turboplanner Posted October 28, 2012 Share Posted October 28, 2012 The other five shook off Howard. 2 Link to comment Share on other sites More sharing options...
Deskpilot Posted October 28, 2012 Share Posted October 28, 2012 Brolly had a stall at the Adelaide Fly and Try open day yesterday. Didn't take much notice of the Harley engine they had on show after I saw the price of their props. Link to comment Share on other sites More sharing options...
petetheprinta Posted October 28, 2012 Author Share Posted October 28, 2012 Bit of blurb on a flying 96B http://m.youtube.com/#/watch?v=LSTRlAx_YSc&desktop_uri=%2Fwatch%3Fv%3DLSTRlAx_YSc Link to comment Share on other sites More sharing options...
facthunter Posted October 29, 2012 Share Posted October 29, 2012 Most of the later HD engines run balancer shafts.(2)If you rubber mount the engine there is hardly any vibration at all. Most aircraft engines are rubber mounted and some move around quite a bit. The V twin is an unequally firing engine, by 50 or 60 degrees which is not the end of the world. I wouldn't mind betting that if it was mounted correctly it could put up with a direct drive. The tip speed might preclude this as it would have to do a fair amount of revs to get the power they are talking about. I would expect it to be fairly economical as the majority of bearing are ball or roller. Nev Link to comment Share on other sites More sharing options...
fly_tornado Posted October 29, 2012 Share Posted October 29, 2012 apart from the question mark over the engine it looks pretty good. Link to comment Share on other sites More sharing options...
rgmwa Posted October 29, 2012 Share Posted October 29, 2012 36' wingspan and almost 22' long! That's a big aircraft. rgmwa Link to comment Share on other sites More sharing options...
turboplanner Posted October 29, 2012 Share Posted October 29, 2012 Most of the later HD engines run balancer shafts.(2)If you rubber mount the engine there is hardly any vibration at all. Most aircraft engines are rubber mounted and some move around quite a bit. The V twin is an unequally firing engine, by 50 or 60 degrees which is not the end of the world. I wouldn't mind betting that if it was mounted correctly it could put up with a direct drive. The tip speed might preclude this as it would have to do a fair amount of revs to get the power they are talking about. I would expect it to be fairly economical as the majority of bearing are ball or roller. Nev My experience with rubber engine mounts started with my eyeballs bouncing like tennis balls and blurred vision (using softer mounts) and smoothing out with Holden rear gearbox mounts which were a lot stiffer, so I'm suggesting some experimenting with various rubber compounds may break up the harmonics Link to comment Share on other sites More sharing options...
fly_tornado Posted October 29, 2012 Share Posted October 29, 2012 I would still be worried about the engine shaking the prop out of the hub at altitude. Link to comment Share on other sites More sharing options...
petetheprinta Posted October 29, 2012 Author Share Posted October 29, 2012 One would hope they know what they are doing, or presumedly they wouldn't bother. Thank heaven for people who are willing to have a go despite the naysayers or where would we be?? (Rhetorical question, doesn't need an answer). I have been informed by Bolly that the prototype will be ready early-mid 2013. My name is down for one, all I need do now is save my pennies. 1 Link to comment Share on other sites More sharing options...
fly_tornado Posted October 29, 2012 Share Posted October 29, 2012 they would sell a lot more if they put a Rotax in front of the windscreen Link to comment Share on other sites More sharing options...
petetheprinta Posted October 29, 2012 Author Share Posted October 29, 2012 Perhaps they are after quality over quantity... Lol. Link to comment Share on other sites More sharing options...
fly_tornado Posted October 29, 2012 Share Posted October 29, 2012 just seems like an opportunity missed Link to comment Share on other sites More sharing options...
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