- The FI system on my 310 has been every bit as reliable and much easier to "tune" than a carb. FI is comparable to other "new" technologies such as Tubliss or Rekluse which I also use. New technologies do present different problems but I adjust. - FI doesn't necessarily add horsepower to a 4 stroke but DI on a 2 stroke has been proven to both widen the power band and increase power and fuel milage. (and probably put and end to the ring ding ding sound) - DI 2 strokes have won competitions dedicated to clean emmisions - they can be VERY clean burning and efficient. - A 40+ hp 150cc 2 stroke with a very wide power band is well within reason with DI. (EDIT) Thanks Robertaccio - you beat me with an actual reference to a recent article.
Dwight, Where the DI gains in power is not only having perfect mixture at all times but also in not loosing any of the fuel charge out the exhaust port relying on an inefficient timed back pressure from the pipe. All pipes are a compromise so they work over a broader rpm spectrum. Now the only loss out the exhaust port will be a "clean" air charge. I think it has been well documented that basic DI gains in the 10% range in peak power and larger percentages when operating below or above the specific pipe timing. Once you see the change to DI there are many possible further improvements and developments of the 2T induction/transfer/expulsion cycles to gain even more advantage. By all means don't sell your current tech as it can be made to work very well but don't dismiss the possibilities of future development. Its all good and other than the environazi's limiting access to our public lands a great time to be a dirt biker.
The same naysaying comments about DI two strokes was said about the FI fourstrokes. Some peoples cups are always half full!
Someday, someday. I can't wait to have a powerful DI 2 stroke that doesn't leave a blue cloud on the trail. Although I am a little worried that the added components will add weight, I'm hopeful that the improved power characteristics will allow a smaller displacement, which would counteract some of the added weight. I do still plan to buy the first readily available DI 2 stroke machine, regardless of manufacturer. I hope it's a Husky, but if it's not, c'est la vie.
Once electronically controlled the possibilities are exciting. Imagine an electronically controlled power valve and expansion chamber to go with the digital fuel and spark curve. This is going to lead to clean efficient combustion from bottom to top, meaning electric like power with less spooge due to cold exhaust at different times in the power curve.
so why is it the dirt bikes are lackin so much behind the marine applications? we have a yamaha 4 stroke thats the cats meow but there are some really nice 2 strokes currently out there as well.
IMO dirt bikes would have already been there if not for the great depression. There were so many left over bikes and parts to build more bikes why come out with a new bike that would insure that the older bikes and parts would never sell.
I just don't think there's a lot of money in dirtbikes for most manufacturers right now. 1) It's difficult to bury development costs in small production runs. Better to just make some insignificant suspension changes, slap on new graphics, call it done and trust that your competitors do the same. That's what the Japanese seem to have been doing for a few years now. 2) People are broke and spending on leisure activities is one of the first things to take a hit.This world wide slump isn't quite over yet. 3) The sport's not in great health either (not at the level where mere mortals race anyway). Quite a few people I know are making their bikes last another season because there's nothing to be gained financially by updating. The release of measurably better new bikes may break this vicious zircle, but I'm sure that the Japanese would try very hard to legislate any new strokers out of competition completely, rather than join the party themselves. They won't want to put warehouses full of unsold big thumpers through the crusher! We live in interesting times.
Disagree Vinduro. My Ducatis are great FI machines and no issues at all. Mt 2 huskies are FI and have never missed a beat.
This thread is like watching the X files - "I want to believe". But of course I don't. It is more like watching a side show magician, all smoke and mirrors. Distract the masses with your right hand so they forget about what the left hand is doing. So we are to assume that the logic in some BMW board room goes like this - let's spend a bunch of R&D on some new unproven technology and then we will apply it to a market that needs developed, such as two stroke dual sport bikes for the world. That makes way more sense than trying to take some existing technology and apply it to a booming market, like 450 dual sports. ......but I want to believe.......
The truth is out there. Where I live, if a street legal two stroke that performed nicely and was light weight hit the market, there would be a sold out waiting list before their wheels ever graced the showroom floor. Maybe it isn't that way in other areas, but people would stampede to buy them in my neck of the woods.
Disagree. Actually it is the Europe emissions and fact that the 125cc 2stroke is one of the biggest sellers in Europe that is driving this. There is no smoke and mirrors and all the 2 stroke manufacturers are working on it. And it IS based on existing tech and also trying to move it forward. Will it be more expensive and more complicated? Sure. Will it offer more tunability, choice of powerbands, perfect running no matter the conditions? sure. Maybe more efficient and powerful too. They already have 250/310/449/511/630 and soon 650 DS EFI bikes so??? Your point? Cars had carbs once too. Does anyone want them back? My TE511 runs perfect, is super adjustable with a $200 add on and has more throttle response than any carbed bike. Can a pump go bad... sure. Also lived through the new generation of four strokes and spent a good part of my life buying JD jet kits, accelerator pump covers and arms and leak valves. Carb divider plates, special needles, o-ring around the AP arm, hours and hours and hours of taking hard to get carbs off and rejetting and adding $400 of aftermarket stuff to. EZ to forget all that but it happened and i have to say my 511 has been pretty much worry free. Never had to take it off once, never seen the pump, never had an issue in over 3500 miles. Would have (and did have) the carb off every other 4 stroke 20 times in search of the perfect jetting trick. I want to "rejet" my 511 I thumb a few buttons at the stop light or trail crossing while waiting for friends to arrive. Thats REAL progress in my mind, no smoke and mirrors. I embrace and enjoy what EFI has brought and hope for the same only better in the 2 stroke world. EFI, water cooling, and e-start, were also once thought not needed and look where we are.
yep, as there is with anything. The Keihn EFI's are VERY good though and i love mine and have had zero issues. Unlike the mass of parts and kits I have bought for carbs over the years to "fix" those machines. My first EFI bike and not looking to go back. More than happy.
I have rode several EFI 2 stroke sleds and they perform great and get far better mileage as well. Its coming.
doing all this in photo shop why leaving the small reflectors on the fork?? all unnecessary weight Robert-Jan
Piaggio (Vespa) has been making PI scooters for years. Bought Aussie technology from Sarich. They suggest more bottom end, better fuel economy and much less emmission issues.
Anyone else notice that the cylinder is mounted directly in line with the clutch cover? I doubt BMW would build another bike with crank mounted clutch - or would they? Either the transmission or the crankcase is missing. (I know it's photo-shopped)
