| Author | Message | ||
     Jaimec |
The other day I came to the realization that V4s dominate MotoGP (with the notable exception of Yamaha and Kawasaki), but IL4s dominate World Superbike (with the exception of the V-Twin Ducs). Why is that? Why is one engine configuration more popular than the other in these two racing classes? Why does an IL4 seem to have an advantage in WSBK, but a disadvantage in MotoGP? Just curious if anyone has any educated guesses? | ||
| Rocketman |
I don't believe they do. The reality is IL 4's to the Japanese manufacturers are traditionally 'bread and butter' which they sell a lot of, so they race them in a streetbike based series. In Moto GP IL 4 configurations are not ideal, so the Japanese concentrate on more suitable configurations to showcase their engineering prowess. Or something like that. As long as they're still successful, they'll still sell streetbikes off the back of them racing, and often winning. Ducati you could well argue had by way of their traditional V configuration, the best of both worlds. Or in this case, best of both race series. What the Italian's lacked for racing was finance, not engineering, until now that is. Now they have both. This is my take on it! Rocket | ||
| Jaimec |
But Honda essentially pioneered the high performance V4 on the street, yet they've apparently abandoned it in favor of the IL4 for their sport bikes. The V4s only live on in the sport touring oriented VFR800 and ST1300. Considering how much they were pushing the V4 in the 80s and 90s I find that surprising. On the other hand, Suzuki only used a V4 for their Madura cruisers and the Cavalcade behemoth, none of which could be considered high performance in any way, yet they use a V4 in MotoGP. Only Yamaha and Kawasaki have remained "true" to the IL4 configuration in all aspects of the sport. | ||
| Jlnance |
Do the WSB rules favor an IL4 over a V4? | ||
| Elvis |
This is mostly speculation on my part, but I would guess the biggest advantage of the V-4 would be narrowness and reduced wind resistance - which offers a subtle, but not dramatic advantage. I would further guess that a good, refined V-4 would do well in WSBK for the same reason, but in the mid to late '80s . . . when literbikes were going at it and more interested in quarter-mile shoot-outs than real racing, the inline 4 configuration became popular as a simpler, better bang-for-the-buck way of getting impressive quarter mile times for the mags. If I remember correctly, back in those days, the sub 11 second quarter mile was something of a holy grail. Kawasaki's original "Ninja" was "only" a 900 and had an impressive combination of power and handling for the time, but when the GSX-R1100 came out, it dominated the key quarter mile with a heavier, less sporting package. Kawasaki (and Honda and Yamaha) responded to Suzuki with their own brute-force inline 4's to try to match the GSX-R1100. Those inline-four bikes that became popular in those shoot-outs of the late eighties became refined and evolved into today's liter-bikes. If Honda had stuck with their V-4 configuration, they may have found that they could offer something that could potentially be more competitive in today's suberbike racing, but those V-4's never seemed to quite catch on with the public and atrophied rather than growing into their potential. Again, that's a lot of speculation on my part combined with what I remember of how things developed, but maybe that will get smarter people than me thinking more about it. | ||
| Jaimec |
But the FIRST production motorcycle to break into the 10s back in those days was the V4 Honda Sabre, followed quickly by the IL4 GPz900 and GS1150E until the V4 V-Max came along and spanked them all... | ||
| Elvis |
Your memory is better than mine. I always liked the Honda V-4's, but they never did seem to catch on like the inlines. I seem to remember some Yamahas (FJ1100, FJ1300?) getting a lot of attention, but age has addled my brain, and I can't remember the details. | ||
| Jlnance |
Can a V4 be balanced w/o counterbalancers? I think it can, but I'm trying to think of potential disadvantages.  | ||
| Jaimec |
A 90 degree V-Four (like the Honda design) has perfect primary and secondary balances, and no rocking couple. Any angle greater or lesser than 90 degrees will require counterbalancers until you get to 180 degrees (boxer engine like the original GoldWing). | ||
| Jlnance |
Given that, I'm at a loss to think of any advantage an IL4 would have over a V4. Does it have any? | ||
| Rocketman |
Honda's biggest problem with the V4 sportsbikes was cost. It's cheaper to mass produce IL4's. I assume this is why V4 configurations in high revving applications has been kept to the minimum quirky few. There certainly has been some greats though. Rocket | ||
| Mcgiver |
Vtwins & vfours can (but don't always), have a disadvantage in overall engine length. Traverse in-line fours can have a width disadvantage, but they need 1/2 as many camshafts and associated drive parts. I think they build what their engineers like, or what they think will help marketing. But what do I know I'm just a nail bender.  Brian | ||
| Trojan |
The only reason that IL4's dominate WSB and not V4's is that nobody is yet making a road going 1000cc V4 to qualify for Superbike rules. Aprilia will launch their V4 next year and if that is succesful we can probably expect others to follow. Ducati could in theory make a cheaper version of their Desmosedicci that would be eligible for Superbike if they could sell enough units. At the moment V4's are out of fashion in the road bike world, but who knows what will happen in the next couple of years? Honda have shown prototype versions of an RCV based sports bike but don't seem in any hurry to build it. | ||
| Jaimec |
At one time Honda had a whole range of V4 Interceptors. They had a brilliant 500cc version, a tariff-busting 700cc version, a larger 750cc "Damn Harley Anyway" version, the limited edition RC45 Superbike homologation "special" and the 1000cc pig. Eventually all but the 750cc version went away, and the 750 became less sport and more sport-touring oriented. | ||
| Anonymous |
Crankshaft whip on in-lines at 20,000 rpm is the biggest reason, especially with wierd staggered firings needed for traction with 250HP in a bike that light. MotoGP is not the street. So don't expect a great rush to this heavy and complex layout in many production bikes. | ||
| Jaimec |
Interesting. That's something I never thought of. Thanks, Anonymous. | ||
| 12r |
I think packaging has a lot to do with it. The emphasis is on making the engine unit very, very small so it can be positioned comfortably in the motorcycle instead of designing the bike around the engine. When I stand back and look at the engine in my R1, it is tiny in proportion to the rest of the bike. The block and clutch/gearbox are stacked against one another and mounted high in the frame. The intake system is behind the steering head and the swingarm is half the length of the bike. | ||
| Jimidan |
Ducati could in theory make a cheaper version of their Desmosedicci that would be eligible for Superbike if they could sell enough units. At the moment V4's are out of fashion in the road bike world, but who knows what will happen in the next couple of years? Honda have shown prototype versions of an RCV based sports bike but don't seem in any hurry to build it. Well, good call dude, as Ducati has just announced it is building a true Desmosedici powered V-4 repli-racer for the street based on it's GP6 990 cc MotoGP racer, the D16RR. It is a $72,500, 200HP, 14,200rpm red-lined bike that Ducati will reproduce 1,500 times. They have already sold 1200 and the bike isn't even out yet. Ducati only make 40,000 bikes a year, yet they smoked the competition in M}otoGP this year. Read the whole story by Kevin Cameron and Nick Ienatsch (I don't know how to pronounce it either), in the latest January 2008 Cycle World, which has just hit my mailbox. | ||
| Diablobrian |
But is that enough units for AMA or WSB homolgation? Talk about an expensive bike to run a race team on though..... 2 man squad, 4 bikes+ unobtanium spares etc. It would HAVE to be a factory effort, or someone made of money that was desperate to lose a large quantity of it. | ||
| Trojan |
Ducati have said that they have no plans to race the 'street' Desmosedicci in Superbikes, although I'd bet that if the 1098 isn't competitive they would change their minds pretty quickly. However as the 1098R is already lapping faster than the IL4 opposition in the first WSB tests I can't see it happening somehow. I had a good look at the Desmosedicci street bike at the recent UK Show, and it is actually pretty subtle and subdued for a UK£40,000 (US$80,000) bike! It has some very neat touches such as the exhaust exiting through the top of the seat unit, but nothing that shouts BLING. Apparently the price includes free 'personal servicing'. The mind boggles ;) | ||
| Jimidan |
1500 units is more than enough to meet the rules...shucks, Harley only made 50 of the VR1000 street bikes to meet the minimum requirements. Talk about an expensive bike to run a race team on though..... 2 man squad, 4 bikes+ unobtanium spares etc. It would HAVE to be a factory effort, or someone made of money that was desperate to lose a large quantity of it. Why would it be any more expensive than any other superbike team. The bike turns out 200 HP STOCK...Why would the parts have to be made out of unobtanium? | ||
| Jaimec |
I think the new requirement, which was imposed SPECIFICALLY to eliminate that Harley nonsense, is 3,000 units worldwide. This is to ensure Superbike is based on ACTUAL production models and not just a few homologation specials meant to bypass the spirit of the event. | ||
| Rocketman |
For £40000 I thought the RR was an absolute bargain when you can buy a special MV 1000 for over £30000 Still, 40k on a 'street' bike is an awful lot of wonga when you can't really do anything but ride it on a track day to enjoy it. Rocket | ||
| Jaimec |
Rocket, Last time I looked, 40,000 was greater than 30,000... | ||
| Blake |
Jimi, It's not the material that Brian is saying would be tough to obtain, it is the actual spare parts. Without serious factory backing, I think he is correct. Meaning no one is likely to be able to go to the local Ducati shop and pick up spare parts for a Desmosedicci. Go Ducati! I totally relished their success in MotoGP this year. | ||
| Benm2 |
Rocket, If I had the 40,000 GB to buy it, I wouldn't need a trackday to enjoy it. I'd make it a point to stare at it every day. You don't have to ride a Picasso... | ||
| Jimidan |
Meaning no one is likely to be able to go to the local Ducati shop and pick up spare parts for a Desmosedicci. True. But it is not like you can drop by your typical HD store (actually, a typical HD store doesn't even sell Buells!) and get parts for an XBRR. I think that we can assume that if someone was wanting to race a Desmosedici (one 'c' not two), that Ducati could see to it that they have a direct line to get parts, just like Buell does for the XBRR, without having to go to a local dealer. I would think that Bison has Henry's number on speed dial, or it is in Walt's top 5 on his cell. However, I would bet that my local Ducati store will be able to order parts for the Desmosedici. The most interesting thing I noticed about the Desmosedici engine is how compact it is. It is much smaller than my 998. I would love to see a team pick up this bike and race it next year in AMA Superbike, but that is not likely. Does any one know what the minimum number of units necessary to be eligible? (Message edited by jimidan on December 05, 2007) | ||
| Rocketman |
Yes Jamie, £40k is greater than £30k the last time I looked too. But here's the thing. MV Agusta F4 1000 Veltro This is the road version of the track only Veltro Pista. My point was, another £7k gets you the Desmosedici RR. As fantastic, and close to a road going World Super Bike racer the MV may be, the road going Moto GP Ducati seems like a bargain in comparison for those that can afford such luxuries. Rocket | ||
| Jaimec |
If you REALLY want to go overboard, go for the MV Agusta F4CC, then. Price in the US is $120,000 (that is NOT a misprint). That's the bike I THOUGHT you were talking about. http://www.mvagustausa.com/web-mvagusta/07_F4_CC.h tml | ||
| Blake |
"But it is not like you can drop by your typical HD store (actually, a typical HD store doesn't even sell Buells!) and get parts for an XBRR." Why would anyone drop by a "typical HD store" for Buell parts, especially for an XBRR?  Only 55 or so XBRR's were produced and they aren't being considered/discussed here for inclusion in a privateer World Superbike racing effort. The Desmosedici is. Go for it. Seems like a significant difference to me. |
