| Author | Message | ||
     Bandm |
https://www.msn.com/en-us/autos/news/bistella-500- boasts-diy-10-cylinder-supercharged-radial-engine- in-a-jawa-frame/ar-AARh1eW?ocid=msedgntp https://www.bistella.cz/gallery/ | ||
| Hootowl |
Integrated supercharger impellers! | ||
| Hootowl |
Impeller is probably not the correct word. | ||
| Ducbsa |
I had gotten the idea that radial engines had to have an odd number of cylinders. Wait until that fellow Milyard finds out about this bike! | ||
| Hootowl |
This might be the coolest thing I’ve seen in years. | ||
| Wcbrracing |
They are called “rotors” in a supercharger, those are twin lobe… Depending how you look at it, it’s a “two row flat 5”.. damn impressive engineering and machining! Bummer at the super low horsepower due to emissions restrictions | ||
| Aesquire |
I had gotten the idea that radial engines had to have an odd number of cylinders It does, per row. 5 cylinder x 2 twin row radial. Odd number radials are a balance "thing". Or at least very few radials with even numbers per row have been built, and none commercially successful. I recall a 4 cylinder based on VW Beetle cylinders. X shaped. Don't think It got beyond prototype. Makes a lovely sound. I think there are/were some 2 row boxer engines, that look like X. But not technically a radial, depending upon your definition. | ||
| Ducbsa |
I should have read/looked closer. For a two row, look here: https://en.wikipedia.org/wiki/Brough_Superior_Gold en_Dream | ||
| 86129squids |
WOW. Thanks for that, Duc. I've always loved those bikes. Here's something I've ALWAYS wanted... might've seen/heard one in person when I was still at Smoky Mountain H-D/BUELL... A Feuling W3!  https://youtu.be/ZaTpxwd-jb4 | ||
| Aesquire |
That Brough is awesome, it's an H engine, like the Napier Sabre, used in the Typhoon fighter bomber. ( one of the fastest piston engine planes at low altitude, used to chase V-1 jet cruise missiles. And blow the guts out of tanks.... ) https://en.m.wikipedia.org/wiki/Napier_Sabre https://oldmachinepress.com/2020/09/20/napier-h-24 -sabre-aircraft-engine/ It's Gloriously Complex! Not a radial, though. It's not just cylinders in a circle. It's the crank & connecting rods arrangement. Your H-D ( based ) twins, the Allison V-1710 & Rolls Royce Merlin and Griffon, ( all V engines ) Napier Sabre, ( H ) etc. All have knife & fork rods to eliminate rocking couple. ( cylinders in line/plane) True Radials have a Master Rod and slave rods pivoting on the Master. All in one plane to eliminate vibes and shorten the crank. A P&W R-985 and other single row radials only have one crank throw, like a H-D, but with typically 3, 5, 7, or 9 cylinders. Per row. Double row engines stack the pancakes.  https://en.m.wikipedia.org/wiki/Pratt_%26_Whitney_ R-2800_Double_Wasp#/media/File:Cross_Section_of_a_ Pratt_and_Whitney_R2800_Double_Wasp.JPG The Bistella 500 has 5 cylinders per row and the master/slave rod arrangement. Even the famous P&W R-4360 with 4 rows, has only one crank throw per row. They just mounted them in a spiral for cooling. The Bistella's integrated supercharger is because the crankcase volume changes aren't adequate or correct to pump the charge air into the cylinders, like a RD400 or typical piston port dirt bike engine. I Clever, cool, and mechanical Art. Or Porn, depending on your attitude. |
