| Author | Message | ||
     Torquehd |
Don't think I'd ever seen inside the 1190 airbox until I saw this vid: http://www.youtube.com/watch?v=y90n0tb0a68  Those intake "risers" are huge. The part that puzzles me is the cast aluminum thing that is dangling above each throttle body. Think it's just a pair of MAF sensors? it looks too "manufactured" to be NOS. It also looks like the air filter is at the front bottom and the air comes in inbetween the frame and front rocker box cover. I hope that intake "snorkel" is bigger than the 1125's. | ||
| 2kx1 |
Secondary showerhead injectors. | ||
| Froggy |
A second set of fuel injectors. Here is a similar setup from the 1190RR  (Message edited by froggy on October 12, 2013) | ||
| Smoke4ndmears |
It's pretty deep. | ||
| Torquehd |
huh. the theory behind this is to start fuel atomization further upstream? surely it's not a fuel quantity issue? | ||
| Jimustanguitar |
That's a big radiator! I like the air filter placement. | ||
| Zac4mac |
Pretty sure the showerheads were added to increase fuel when the 1125 got bumped to 1190. Might have been the DSB 1125 tho, but the original injectors were starting to pool fuel, IIRC. Z | ||
| D_adams |
I'm thinking those were 1190 RR specific for their introduction. I don't recall them ever being on an 1125, but I've been known to be mistaken a few times. | ||
| Torquehd |
i hate to say this, but that seems like a band-aid way to address the problem. it seems hard to believe that there aren't any companies who could produce a single set of injectors able to deliver enough fuel. Look at how far diesel injectors have come in the last few years. | ||
| Smoke4ndmears |
shower head injectors have been around for years. useful for high volume, high rpm situations i think. | ||
| Darth_villar |
It seems to me like it is a physical size issue. If they couldn't fit another injector in an ideal location without ruining intake flow, showerhead injectors makes sense. There would be little flow disruption, and the fuel would atomize completely. I expect the showerhead injectors are used at the high RPM/Load range. Every injector has limits to it's duty cycle, and without running multiple injectors they may have had problems with low RPM smoothness without this addition. This is all my interpretation however... Phil | ||
| Satori |
Gas and diesel fuel injection are completely different animals. Common fuel pressure for a modern diesel is right about 26,000 PSI, with some real modern systems as high as 160,000 psi. You can vary the volume greatly at that and get excellent atomization. The 26k systems need fuel pumps that take anywhere from 10-40 hp to operate just the pump. Gas systems are typically 30-90 psi, one of the most common pressures is 50 psi. At that when you have a high volume injector, at low use they don’t atomize the fuel well, which means crappy running and hard to meet emissions. So the solution is to use two sets of injectors, one with a lower volume for good atomization, and a second set to add the volume only when absolutely necessary. (Message edited by Satori on October 13, 2013) | ||
| Dannybuell |
Satori - great explanation! thx! | ||
| Sir_wadsalot |
Satori beat me to it....nice. Yeah, single injectors at a bajillionty PSI will work great at 10000 RPM and be absolutely horrid at 2000. On a diesel you're going from 800 to 3000 RPM. That, and how big of a fuel pump do you really want on the bike? The "showerhead" secondaries are the common way to go, especially getting up near that magical 200hp mark. Far cheaper and simpler than trying to completely redesign the entire fuelling system. | ||
| Jimustanguitar |
Diesel injectors usually inject directly into the cylinder. The heat of the compression ignites the fuel charge, and the "ignition timing" is controlled by when the injector opens. Most modern cars inject directly into the cylinder as well, but the ignition doesn't happen until the plug fires. The "shower head" injectors are commonly referred to throttle body injection. It would be a technological step back for Buell on a production bike. My suspicion is that this is a race only thing... I guess we'll see in a day or two. |
