Blind Spot's Unkinkable Fuel Line Mod.

[Blind Spot]

Originally Posted by ks_cowboy

Alright guy since none of you have been brave enough to try this I had to man up and do it myself. I haven't done extensive testing yet but my bike runs better than with a kinked line and hasn't burst into flames yet. Getting the fittings in was a bitch but I don't think they are coming out without a knife. I'll keep you updated as I put more miles on the bike.

[TDDragon]

Originally Posted by TKO

Very nice work. Thanks for doing all the hard stuff for the benefit of others.

If I would have tried to come up with this mod . . .

LOL

[ks_cowboy]

Blind spot have you had a chance to run yours yet? This was a great idea on your part it fits in there just as well as the stock one, but with almost no chance of kinking. I am going to have my bike on a dyno in the next couple of weeks. I haven't made any other changes since its last run so it should be interesting to see. It feels no different than stock to me, and if that proves true you have saved people a lot of money and issues. Thanks again for thinking this up.

[Blind Spot]

Originally Posted by ks_cowboy

Blind spot have you had a chance to run yours yet? This was a great idea on your part it fits in there just as well as the stock one, but with almost no chance of kinking. I am going to have my bike on a dyno in the next couple of weeks. I haven't made any other changes since its last run so it should be interesting to see. It feels no different than stock to me, and if that proves true you have saved people a lot of money and issues. Thanks again for thinking this up.

Honestly, I never had the tank up again so I never installed. (I've a million half finished projects).

But yeah, I'm preoccupied with other things ATM.

http://yamahafz1oa.com/forum/showthread.php?t=107680

[ks_cowboy]

Don't know how I missed that thread. Heal up quick bud

[PapaGeno21]

Is this someting that was fixed for the 2010 models, or will I have a "Kinked" fuel line as well?

[Blind Spot]

Originally Posted by PapaGeno21

Is this someting that was fixed for the 2010 models, or will I have a "Kinked" fuel line as well?

The fuel line part number is the same 06-10. This issue was never 'fixed' as it only breaks when you/your dealer/mechanic raise the tank too far before disconnecting and/or you don't set it correctly when lowering the tank.

[Rockhound]

Yep, and you don't realize how much this effects low rpm drive-ability. No more surge and it smoother throughout the rpm range.

[Fizzman]

Personally, I don't see how a restricted fuel line could affect low rpm performance. If fuel flow is reduced, it only stands to reason that situations requiring high fuel flow would be affected, such as larger throttle openings at higher rpm.

[Blind Spot]

Originally Posted by Fizzman

Personally, I don't see how a restricted fuel line could affect low rpm performance. If fuel flow is reduced, it only stands to reason that situations requiring high fuel flow would be affected, such as larger throttle openings at higher rpm.

People have posted dynos of decreased power in the low end with kinked lines and of course, a substantial drop in peak HP. I think it's in the ballpark of 30HP loss...

The low speed driveability may be due to the fuel pump having a harder time keeping a consistent pressure as injector duty cycle changes. The EFI assumes that the fuel pump will always be providing 47 PSI under all conditions, but the pump has to work a differing rates to maintain that pressure at different throttle positions. Since the ECU/EFI only know to meter fuel based on injector timing based on RPM/throttle position/etc. unexpected/unaccounted for fluctuations in fuel line pressure may cause driveability problems.

Pure speculation, of course.

[Fizzman]

There should be a regulator that keeps the fuel pressure where it should be and the rest of the fuel just gets returned to the tank. The fuel pump just runs at a pressure higher than the regulated pressure.

[Blind Spot]

Originally Posted by Fizzman

There should be a regulator that keeps the fuel pressure where it should be and the rest of the fuel just gets returned to the tank. The fuel pump just runs at a pressure higher than the regulated pressure.

Everything's self contained on this bike (Pressure regulation, pump). Even a regulator would have a hard(er) time keeping up with a kinked line. I don't see any description on fuel pump operation in the service manual. Pressure before the kink and after the kink may be different if the kink is significant enough.

Though, there is this weird device on the fuel rail between the 1-2 injectors. It looks like an on-rail fuel pressure sensor, but has no leads or vacuum hoses coming from it for the ECU/mechanical function.

[Fizzman]

Well, no matter. If it's kinked, it should be replaced and improved upon, which your idea addresses.

[Adjuster]

Originally Posted by Blind Spot

Everything's self contained on this bike (Pressure regulation, pump). Even a regulator would have a hard(er) time keeping up with a kinked line. I don't see any description on fuel pump operation in the service manual. Pressure before the kink and after the kink may be different if the kink is significant enough.

Though, there is this weird device on the fuel rail between the 1-2 injectors. It looks like an on-rail fuel pressure sensor, but has no leads or vacuum hoses coming from it for the ECU/mechanical function.

Might be a fuel pressure dampener. (Smooths out the pulses from the pump, reduced noise, and the injectors are fed with a more constant pressure this way too.)

It's a pretty common item on many port fuel injected designs, and like you mention, looks like a fuep pressure regulator, but has no vac lines etc.) On many Toyota's, it is part of a banjo bolt for the feed line from the tank/pump.

Most of the new Port injected designs do not have a fuel system return line anymore, so the fuel pressure regulator is part of the pump in the tank. (Like on the FZ1, as you noted.) These "returnless" systems are cheaper to build, but the downside is they are more expensive to repair in my experience. (You often have to buy the entire pump if something goes wrong, and since it now includes the fuel pressure regulator, and not just a fuel pressure bypass, it's more expensive.)

Hey, hope you are getting well. I was just reading about your accident, and my instinct says someone might have clipped you from behind you, but very light, so you can't see any impact. Especially if you were going slow on the corner, and have done this corner many times. Bumpy road, sand/gravel and other things like just a little spilled oil or coolant can be nasty however.

The advice to go check it out at that same time of day is a good one. I've also had some claims in the past where I canvased the area, talked to people who could have been around, and actually found a local "street person" who saw the accident, but was never put on the PD Report. That recorded statement at first was discounted, but upon more work, flipped the entire liability decision when I also found a corresponding witness who worked in the Denny's on the same corner, and saw the same thing.

The girl who was found at fault was pissed. She had lied, the physical damage supported that she lied, but we had an insured with credibility problems. These two witnesses, and the physical evidence made all the difference in the world. (And I did not have to pay for that chick's damages, or consider her medical/injury claim any further.)

I spent perhaps 3 hours on that claim above what I normally did for a loss, but it paid off big time.

I'd say a few hours of your time might pay off for you as well. You never know untill you go look/try.

Again, good to have you around still, and get well soon!

[Blind Spot]

Originally Posted by Adjuster

Might be a fuel pressure dampener. (Smooths out the pulses from the pump, reduced noise, and the injectors are fed with a more constant pressure this way too.)

It's a pretty common item on many port fuel injected designs, and like you mention, looks like a fuep pressure regulator, but has no vac lines etc.) On many Toyota's, it is part of a banjo bolt for the feed line from the tank/pump.

Most of the new Port injected designs do not have a fuel system return line anymore, so the fuel pressure regulator is part of the pump in the tank. (Like on the FZ1, as you noted.) These "returnless" systems are cheaper to build, but the downside is they are more expensive to repair in my experience. (You often have to buy the entire pump if something goes wrong, and since it now includes the fuel pressure regulator, and not just a fuel pressure bypass, it's more expensive.)

Hey, hope you are getting well. I was just reading about your accident, and my instinct says someone might have clipped you from behind you, but very light, so you can't see any impact. Especially if you were going slow on the corner, and have done this corner many times. Bumpy road, sand/gravel and other things like just a little spilled oil or coolant can be nasty however.

The advice to go check it out at that same time of day is a good one. I've also had some claims in the past where I canvased the area, talked to people who could have been around, and actually found a local "street person" who saw the accident, but was never put on the PD Report. That recorded statement at first was discounted, but upon more work, flipped the entire liability decision when I also found a corresponding witness who worked in the Denny's on the same corner, and saw the same thing.

The girl who was found at fault was pissed. She had lied, the physical damage supported that she lied, but we had an insured with credibility problems. These two witnesses, and the physical evidence made all the difference in the world. (And I did not have to pay for that chick's damages, or consider her medical/injury claim any further.)

I spent perhaps 3 hours on that claim above what I normally did for a loss, but it paid off big time.

I'd say a few hours of your time might pay off for you as well. You never know untill you go look/try.

Again, good to have you around still, and get well soon!

Unfortunately, it's an intersection with no businesses in view of that street. My only real hope would be to sit on the side of the road with my bike and gear with a sign that says, "look familiar?" and hope that anyone that does recognize me is kind enough to stop... and that the probably ~5-8 cars that would have been around at that time happen to be there at the same time I was.

[rafartist]

Ive now been running 5/16" line for a week or so now and no problems at all. Bike runs better all around from 0-10k rpm's and runs cooler on the highway. I had no idea how much HP i was missing till I did this mod. I actually have a bike that acts like a proper liter bike. Now all I gotta do is ditch this Conti road attack rear cause it lights it up at any kind of an agressive take off. I now find myself doing ALOT more rolling burnouts since I have an excuse to NEED a new rear now.

[Blind Spot]

Originally Posted by rafartist

Ive now been running 5/16" line for a week or so now and no problems at all. Bike runs better all around from 0-10k rpm's and runs cooler on the highway. I had no idea how much HP i was missing till I did this mod. I actually have a bike that acts like a proper liter bike. Now all I gotta do is ditch this Conti road attack rear cause it lights it up at any kind of an agressive take off. I now find myself doing ALOT more rolling burnouts since I have an excuse to NEED a new rear now.

Glad it's working for you. The 5/16 hose I bought just slipped on way too easy for comfort for me.

Are you able to accommodate the 5/16 hose minimum radius requirement?

[rafartist]

I used the whole piece that came in the box, I cant remember wether it was 18" or 24"s long but when setting the tank down it curled right up into a nice pattern that was perfect. I think it made about an 11" diameter circle (if that makes any sense)??

[Fizzman]

Well, I did the mod today. Haven't ridden it yet, but no leaks thus far. I also yanked the charcoal canister which was held in place by some trick alloy allen bolts. The old fuel line seems way too brittle and flimsy to stand up to much. Glad I changed it.

[Blind Spot]

Originally Posted by Fizzman

...which was held in place by some trick alloy allen bolts.

What ID hose did you buy? I have my premade 1/4th ID hose and 5/16th if you want to try both.