Many riders have no idea what a fuel rail is, or why using our new one is so important, so I’ll explain.
The throttle body on the left uses the stock fuel rail.
The one on the right, the new BDSB fuel rail (with the red bracket).
The fuel rail is the actual part that joins the fuel line (rubber line with the hose clamp) to the actual injector (part with the two metal tangs)
Hopefully this picture below makes it clear. The stock fuel rail, on the left, routes the fuel through a U turn, where it struggles to move quickly enough when needed, to adequately feed the fuel to the injector (part with orange O ring and blue dot).
The stock rail has 2 turns with varying size holes and sharp edges. These are things that don’t help fuel flow.
The new BDSB rail is on the right. As you can see, the fuel now comes straight out of the smoothly curved fuel line and straight through our rail, into the rear of the injector.
This design ALWAYS allows the fuel to flow smoothly into the injector.
The new fuel rail was designed as a way to try to fix the bike running out of fuel. With our attempt at trying to make the 500 run 175 mph to set a land speed record, it was quickly discovered that the bike was leaning out when being held wide open for more than about 10 seconds. It was this badly designed stock fuel rail, that ended up being the problem.
A funny thing happened though, when the new fuel rail was in place...
SOME OF THE ADDED BENEFITS OF THE NEW RAIL WERE:
1. The bike started easier. Reports from many of the people we sent the fuel rail to for initial feedback said their bikes started much easier. The bikes idled smoother too.
2. The throttle response got much better. So much so that most of the people ended up turning their TPS setting down, from where they had turned it up to. It was apparent, that the bikes needed to run richer, to make up for this “lag time” in fuel delivery, that the stock fuel rail was causing.
3. Because the fuel delivery was much more instant, along with the throttle response, the amount of a bikes FLAMEOUTS DRAMATICALLY DECREASED. When a bike flames out, it is usually a result of the throttle being closed and then cracked open quickly.
This creates an instantaneous rush of air. If there is not an instantaneous rush of fuel keeping up with it, then the rush of air causes the bike to stall. The new fuel rail let’s the fuel keep up, and the much lower amount of flameouts proves this.
4. Even with the leaner TPS settings on our bike, we turned the TPS down from .70 to .65, with the XCFW map, the acceleration, pull from lower throttle positions, and general get up and go at all throttle openings was improved. All the other testers, on both 350’s, 450’s, 500’s and 501’s got the same results.
There was a mix of EXC and XCFW maps. TPS settings varied on the bikes and the riders preferences. Experimenting with the changing of TPS settings after installing the new fuel rail is all up to you.
Even the dyno results below proved amazing.
The red line shows the increase in pulling power, from just the changing of the fuel rail. The bike was a stock 2016 500 XCFW, with the tps at it’s stock setting of .59. The dyno just verifies what your “butt dyno” feels.
You ride it and think “there’s no way”, but there be a way. The BDSB fuel rail way.
It’s funny that something so little, has so much impact. Like a splinter… but in a good way.
The hole in the new rail is radiused as the fuel leaves the line, so that there is even a smooth transition there, and the hole size is optimized, so that there is no upset in fuel delivery, when the injector is slid into it.
Honestly, for $79.95, this is the first and biggest improvement you can do to your bikes engine performance.
It fixes a weak link and you build upon it. No matter what you have done to your bike, if you have the stock throttle body and aren’t using this, then you have a weak link and can make an easy improvement.
YOU’LL WANT TO RE USE YOUR STOCK 2013-16, UNCUT FUEL LINE WITH THE NEW RAIL, SO THAT IT WILL CLEAR BETWEEN THE THROTTLE BODY AND FRAME.
IF YOU HAVE A FILTER, SUCH AS A GOLAN, IN YOUR LINE, THEN YOU’LL NEED TO PUT THE FILTER NEXT TO THE QUICK DISCONNECT OR BETWEEN THE TANK AND THE DISCONNECT, JUST TO MAKE SURE IT CLEARS EVERYTHING.
THE 13-16 STOCK LINE HAS THE PRE-FORMED BEND IN IT, WHICH CLEARS THE FRAME AND MAKES THE BEND IN THE LINE NICE AND SMOOTH.
OKAY, NOW IF YOU'RE WONDERING HOW HARD IT IS TO CHANGE OUT THE FUEL RAIL, LET’S TAKE A LOOK AT HOW EASY IT CAN BE…
First, all you need to do is remove the seat, fuel tank, and muffler.
Next remove the upper and lower shock bolt.
Then lift the shock up and it slides right out through the rear. That's one cool thing about the linkless bikes.
Now remove the bottom two subframe bolts, and loosen the top two, but don't remove them.
Loosen up the clamp that holds the airboot to the throttle body.
Now just yank upwards on the subframe and it will come up. It may stick a bit where the airboot has to come off of the throttle body but it will come up if you aren't a sissy boy. You can snug down the top sub frame bolts and it will hold it up, so that you can easily work on things.
Yippie yippie you little hippie. We now have access to the throttle body. You will loosen the clamp that holds the body into the front rubber boot. Loosen it quite a bit. Pull and wiggle on the throttle body and it will come out. Again, don’t become a crying little sissy like this one guy, who swore KTM glued in only HIS throttle body. They didn’t, and it will come out.
Then, undo these 2 phillips head screws and your fuel rail and injector will come out. Pull the injector from the fuel rail. You don’t need to take anything else off of the throttle body.
Go ahead and put the stock fuel line onto the new rail and clamp down with supplied clamp. Put a little grease on the orange O ring on the injector, and slide it in easily, into the new rail. Time to install back onto the throttle body and tighten down with the new, supplied, allen screws.
The new rail installs just like this. Clip the injector clip back on and push the body back into the rubber boot. The rubber line that goes to the airboot, routes over the top right of the body. Don’t tighten the front clamp down yet. Put some grease on the front, inside of the of the airboot, before you lower the subframe back down, as it will make it much easier for the boot to go back over the back of the throttle body. Loosen the subframe bolt if you tightened one down and lower the frame down. Between spreading the subframe and working the airboot over the throttle body, it should go together easily.
It’s easy to get the rear airboot completely seated over the throttle body by keeping the front clamp loose. You can move the throttle body around that way and get it in there easier. This is also why you want the shock off, so that you can see to do it much easier. Now tighten it all up and you’re good.
The extra, longer piece of fuel line goes here. The new clamps will tighten it down. Yes, I know there is one missing in this pic. Make sure it runs with no kinks.
If you are smart enough to be using our 90-Degree fuel fitting on the tank side, then you won’t need the extra piece of fuel line as long as it is. You can cut it to the size you think is right.
So that’s it! Now you know what’s involved to install these fuel rails. Your part will come with instructions so you’ll have everything you need to get your fuel system flowing optimally.
You’ll also want to check out our options for the In-tank Fuel Filters, 90-Degree Tank Fittings, and Large Capacity Fuel Filters to see if we carry them for your year and model bike.
If you’re ready to pick up this fuel rail, you can do so below for only $74.95.