| Author | Message | ||
     Fresnobuell |
Sent from FMF. Looks like the midrange is equal to stocker. Low end and high end are definitely helped. What do y'all think?  | ||
| T_man |
That looks pretty good considering the design of that exhaust! Better than the rest of the straight through slip-ons for sure. | ||
| Fresnobuell |
My thoughts exactly. I give any pipe props if it can match the stocker without modded fueling. | ||
| Tbenson |
I just might be on the list for one soon, thanks Fresno! Troy | ||
| Steeltech |
Alright. Important question: Does this run include the silencer portion of the system or not? Also, can we get the numbers with/without the silencer depending on which one is shown? | ||
| Redscuell |
Hideous result for the dollar. See my post under 'first dyno run' thread. Oh, well, at least the fmf is lighter for those high-speed runs (I use square tyres on my track bike, don't you know). | ||
| R2s |
It does seem to have a dip in torque from 5 to 8k where the stock is flat. I wonder if it is noticeable. Also like Steeltech said, is that with or without the DB killer. It still looks good with a 8hp gain at 5k and about 15hp at 10k. If it really gains 10% with not fuel map, that would be damn good. | ||
| Fresnobuell |
Hideous result for the dollar. If this dyno chart is the real deal, it is an outstanding result for the dollar. | ||
| T_man |
I agree with Fresno here - if indeed these results can be replicated (without fudging environmental conditions) by anyone who bolts on an FMF Apex slip-on this is outstanding value. However, R2s; if you look at the scaling on the left the most it makes is maybe 10hp more anywhere with more accurate results at 5k = 4hp gain and 10k = 8hp gain. | ||
| R2s |
Yeah, my bad. I was thinking 10 per gradian and it is only 5. So we are looking at more like a approx. 5% gain. | ||
| The_rock |
The dyno run I posted is not the one with the insert. Stay tuned and I will post the insert run. Expect to see hp/torque loss below 4000 rpm. | ||
| Donutclub |
I'm currently running the Apex with the db killer and I think there's a power loss over the stocker in the entire rpm range. It sounds good, but I'm not too happy with the "apparent" power loss. I'd be interested in seeing the dyno run to see if my hunch is right. On another note, I installed a Protune 3 today and it made a significant difference above 4k (with the db killer installed). However, below 4k, it's not running as good as the stock pipe. My next step will be to remove the db killer. | ||
| Badlionsfan |
If u guys take up a collection for me, I'll have enough money to buy the pipe. The payoff for you is I'm local to xb9 Dave and we'd be able to come up with a tune for this pipe, with and with out the db killer I bet. I'm not holding my breath on the fundraiser, so no pipe for me til this winter, gotta fix the cosmetic crash damage first. | ||
| Donutclub |
Just removed the db killer and took it for a ride. It's much improved. The Protune was a simple plug and play and it's working great. Very happy with the current combination of the FMF Apex and the Protune 3. Unfortunately, I noticed that my clutch weep hole is now leaking again. It'll be off to the shop again. | ||
| Fresnobuell |
So what is the verdict on the popping on decel with the FMF? Will increasing fuel via the AFV help eliminate the popping? | ||
| Slypiranna |
No, it won't help the decel popping. Reduce fuel pulse width within decel load regions. Nice thread tho!  Happy tuning!  | ||
| Xbswede |
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| R2s |
Still would like to see a dyno run with the DB killer in. | ||
| Fresnobuell |
Rec'd an email regarding the dyno with the DB killer and it appears that FMF is modifying the insert and the dyno will happpen soon. | ||
| Slypiranna |
Sorry gents, I got the decel pop issue in reverse...memory isn't what it used to be. The master has corrected me and here is his solution; "It needs more fuel in the decel region; popping on decel is caused by a lean condition. There is a parameter in the ecm 'Decel Correction'; stock it is at 100 (%, no correction) on the 1125's. When I did my open exhaust calibrations, I got rid of the popping by changing this value to 130. It totally eliminates it and worked like a charm. The popping is severe with the Jardine and HMF. I first tried richening (and leaning) the decel region seed values in the maps without much success." Hope that helps! | ||
| Dentguy |
"It needs more fuel in the decel region; popping on decel is caused by a lean condition. Correct. | ||
| Bob_thompson |
Question here guys: If this "popping" is happening in deceleration, the throttle is probably close to or completely closed and very little fuel is going into combustion and its "off" power. If this is in fact the case, what harm can there be to the engine, except for the noise factor to the rider? | ||
| Donutclub |
Hmm....modifying the db killer insert? I wonder if my hunch was correct? | ||
| Fresnobuell |
Hope that helps! That helps alot. Thanks. I assume the O-S-B utility lets us modify the "decel correction" parameter per MM's last post? | ||
| Al_lighton |
Bob, your observation is mostly true. Excessive popping IS a bit harder on the exhaust system/muffler packing, but for the most part is fairly harmless. By definition, it's happening under low load conditions. Popping on decel is simply unburnt fuel in the combustion chamber igniting in the exhaust system. The reason why many free flowing exhaust systems pop so badly is less because of how rich or lean they make the mixture from bolting them on, and more because of how much reversion they have. There is net exhaust flow OUT of the pipe due to expelled combustion gasses. But there are also pressure waves that are moving air in both directions. You can kind of think of it as an AC wave impressed upon a DC current, but in this case the DC current is still pulsed flow. That AC component can draw external O2 rich air BACK into the muffler outlet, where it can react with unburnt fuel in the muffler and hot igniter sources. Take a puddle of gas and put it on the ground. Throw a match in it. It goes wooomph, not POW!!! Partially fill a small container with gas and some O2 rich air, ignite it, and it goes POW! Same thing with firecrackers and such. If you want a loud POW!, you need to contain the explosion a bit. KInda like what a muffler shell does... You can make popping go away by leaning the mixture, or you can make it go away by richening it. Either way prevents the mixture from becoming combustible in the pipe at all. Lean just prevents there from ever being enough there to explode. Rich are the bikes spouting flames on decel (i.e., think Foggy Petronas triples of World superbike a few years ago....WOW!!) Richening for decel pop reduction costs mileage and pollutes more. I think the real disadvantage of excess lean decel cut to prevent popping is that there is benefit to have some fuel cooling on the valves. I pretty sure decel fuel cut is disabled on the XBs when the engine is running hot because of this, not sure about 1125s, though When you put a QMI module in the XB Jardine RT-1 pipes, decel popping is MARKEDLY reduced. The biggest reason is because the reversion flow at the tip is attenuated. In the case of the FMF pipe, a quiet cone at the FRONT of the muffler is less likely to have the same decel pop reduction effects. But there may be other benefits of having it at the front rather than the rear. I dunno. I don't know enough about the 1125 algorithms to know if they're the same. The biggest problem on the XBs in reducing decel popping via the fuel tables is that you can have adverse effects on AFV stability if you tune it just for pop reduction. BTW, this is also why it's important to seal up the pipes at the joints. Exhaust leaks OUT can also be O2 leaks IN. That O2 can react just like reversion O2 can to ignite unburnt fuel in the exhaust system. Al | ||
| Fresnobuell |
So Al, is this popping something we should accept? Sounds like the alternatives of lean or rich on decel are not that attractive. | ||
| Blake |
Al as usual nailed it. Beware so-called "masters" who claim that "popping on decel is caused by a lean condition." | ||
| 01xjbuell |
Wow, Al, thats brought this whole popping issue to a new level with me. Very well explained. I've added alot of fuel with my system (not FMF) and it does pull harder, and decel popping has been cured. Oddly the non-existent engine braking with the stock exhaust is now very nice. Nick | ||
| Bob_thompson |
Very well explained Al. Your explanation cleared up a lot of misunderstanding I had on other issues as well. With my own system and stock ECM I just get a little popping but not very much, probably, as you have stated, because my fueling is still lean enough down low to act as you have said. I also have an insert in the end of mine. Thanks much my friend, well done. Bob (Message edited by bob_thompson on September 26, 2009) | ||
| Avc8130 |
Al, Is there a quiet insert for the Jardine now? ac |
