| Author | Message | ||
     M1combat  |
I've heard that plenty of flat trackers configure their V-Twins as a "twingle". From what I hear, this means that they setup the cams and timing so that both cyl's fire on the same revolution. What are the advantages and dis-advantages... Anyone know? | ||
| Imonabuss |
Disadvantages are that the vibration increases and engine life goes down. The advantage of a "twingle" is that it has better traction, which helps on slippery tracks. With the power delivery characteristics of the XB's and the traction capabilities of modern tires, it would be a bad choice for the street or pavement. However, idf you wanted to flat track an XB, or ice race it...then maybe... | ||
| Bud  |
sort off big bang cycle ? like the v5 honda | ||
| Imonabuss |
Yep. For the same reasons. On pavement when you have 200+ HP (I've heard 250 available on the Honda), searching for traction becomes a real issue! | ||
| Blake |
I cannot stop watching "Faster" and the bonus DVD "Faster & Faster", especially that slide-wheelie-kneedragging clip of Gary McCoy. I'd sure like to here the Duc GP machine in its big bang mode. I had heard rumors that Ducati Corsa had tested it and found some beneficial results. Don't think they've tried it in the race though. Might be that the V4 in big bang mode over-stresses the bottom end. Interesting stuff. It is a bit counter intuitive to me that a big bang cycle provides better tractability. All that transient non-linear behavior with tire grip comes into play I guess. | ||
| Coldwthrrider  |
Blake, did you order it off the website or get it at a showing? I ordered the DVD pre-release and it never came (never got charged). The website for ordering looks different now, maybe it will work. I take it it's worth it? | ||
| Trenchtractor  |
'I cannot stop watching "Faster" and the bonus DVD "Faster & Faster", especially that slide-wheelie-kneedragging clip of Gary McCoy.' Aussie Aussie Aussie... Oi! Oi! Oi!! | ||
| Nick |
The Harley setup (same pin used for both rods) effectively means the bangs come in the same revolution anyhow (315 degrees apart rather than 360). So you automatically get what you want with a Buell! To modify this you would need a different crank, in fact I'm not sure how you'd do it in a Harley motor (have both fire at exactly the same time), as you'd need the rod journals to be separate and the motor is not designed this way. It's a significant change. Other V-twins would be way easier though. | ||
| Jprovo  |
Nick, What they're talking about is making the cylinders fire 45 degrees apart instead of 315. A buddy of mine and I did a similar thing to an Yamaha I4 by making it a "big bang" motor. Cylinders 1 and 4 fire together and 2 and 3 fire together. The bike was fun, with a completely different feel, but didn't have enough flywheel to idle down smoothly. James (Message edited by jprovo on January 05, 2005) | ||
| Fdl3  |
Here is an intriguing idea. The HD 45-degree V-Twin engine can really be considered a rotary engine (think WWII aircraft engines, not Mazda Wankel engines). This is true because of the single-pin crank. Think about how many cylinders some of the WWII bomber engines used! What if one or more cylinders could be added to the HD V-Twin, still using the single-pin crank? Packaging constraints may limit this to one, maybe two, extra cylinders. Cooling constraints may make this unfeasible in a motorcycle. I have no idea what the vibration level would be. Anybody else wonder about this?  | ||
| Mikej  |
http://www.motorcyclecruiser.com/roadtests/w3/  | ||
| Fdl3 |
MikeJ: Wow, thanks for the link! That is a must read - and to think the idea works, too! The extra cylinder is certainly a package issue. Cooling must be an issue, but perhaps not much. I had not thought through how an extra 45-degree cylinder would create a total of 90-degrees between the first and third cylinders - 90-degrees being the magic primary balance angle for V-Twins and all. So vibration is not a concern - even less of a concern than the current 45-degree engine. | ||
| Fdl3 |
Here is another link for info on the W3 engine: Feuling W3 Also, here is a dyno showing rear-wheel power from the site above:  | ||
| Midknyte |
That thing is sick! I love it! | ||
| Jprovo |
It was a sad day when Jim Feuling died. His company went on the Block, and I haven't been able to find more info about what is going to become of it. I hope someone has some info that they can share. James | ||
| Craigster |
I agree, Jprovo. Fueling was a genius. It is sad that he is gone. | ||
| Nedwreck  |
If you took the middle cylinder OUT of the W3, would you have a Ducati (90 deg. v twin)? Sorry, I'm just sitting here waiting for the meds to kick in.* =) Bob *Nah, I'm kidding, there are no meds to help people like me. | ||
| Fdl3 |
Nedwreck: I don't think the Ducati V-Twins use a single-pin crank. |
