jhenley17 Posted September 22, 2016 Share Posted September 22, 2016 I think I may have received an irregular bike. There's no mistaking it, I still think I've lost traction every time it kicks over. My pull from a dyno day shows a pretty nasty dip as well.Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
SlfAwre Posted September 23, 2016 Author Share Posted September 23, 2016 4 hours ago, smoke4ndmears said: Man, was the juice worth the squeeze? Looks great but $$$ Yes. 5 hours ago, CandyRedRC46 said: Lot of common misconceptions out there about how the FI system and emissions systems work together, power commanders and popping etc... I have a 6th gen, not an 8th, so I can comment on my 6th and assume that most of it carries over to 8th gen The popping does not have to do with any mapping that a power commander will iron out. The popping only occurs, when the throttle is shut at higher rpms (aka over run) and there is an overly lean condition (15-20:1 plus AFR), where the mixture is too lean to completely burn in the combustion chamber and can accumulate in the exhaust port/ header/ catalytic converter/tail pipe/muffler and can combust there instead. This overly lean condition can occur due to many reasons, most revolving around EPA regulations. One reason is the Pair valves that everyone knows all too well. The pair valves can be blocked off easily, so they are no longer letting fresh air into the exhaust system, to continue the burn outside of the combustion chamber. There is debate to whether or not they are needed to keep the catalytic converter happy. The other reason for the overly lean condition on over run that causes the popping on decel is call the "Fuel cut". Fuel cut on over run is mandated by the environment protection guys, so that you are not wasting fuel and creating emissions when you do not need to. There is no reason in the eyes of non enthusiasts to be dumping fuel in, when you are trying to slow down, even if it makes the bike smoother and more enjoyable to ride. Basically when the throttle is closed, at certain speeds and rpms, the injectors are phased out or shut down entirely. This also accounts for a lot of the harsh on/off throttle transitions of newer fuel injected bikes (I believe even some late carb'd bikes shut the pump off on overrun), because the injectors are coming on and off, on top of the throttle being opened or/and closed. It is different in every gear, but on my sixth gen it is more prominent in gears 4/5/6th than 1/2/3, where in stock form there would be zero fuel on over run in gears 4-6th and then when down shifting into 3rd and continuing to engine break, the injectors would slowly begin to get phased back in and the popping would then begin to occur. The fuel cut, isn't something that you can just iron out with a power commander, because even if you dump 50% more fuel in the 0% throttle column at higher rpms, 50% of zero is still zero... That is why experienced tuners do not touch the 0% throttle column. That is not to say power commanders aren't great at fixing the lean mapping symptoms of the factory fuel mapping, but they can't eliminate the fuel cut. The only way of eliminating the fuel cut is with an ecu flash, fuel cut eliminator or rapid bike's engine brake control. That last bit about harsh on/off throttle transition is exactly what I want to fix. My plan is to remove the air injection stuff first, maybe that will help w the popping but if I understand you correctly the fix for the on/off throttle is more involved and has to do with the fuel cut. My guess is the rapid bike stuff will fix that-as well as lean map overall? If I go that route, what is the risk to the cat that you mention? Link to comment Share on other sites More sharing options...
Member Contributer fink Posted September 23, 2016 Member Contributer Share Posted September 23, 2016 13 hours ago, jhenley17 said: I think I may have received an irregular bike. There's no mistaking it, I still think I've lost traction every time it kicks over. My pull from a dyno day shows a pretty nasty dip as well. Sent from my iPhone using Tapatalk Post up the printout for us all to see please. Have to say I have never experienced any harsh transition from vtec kicking in or lost traction. Get someone else with one and see if you can swap bikes. Link to comment Share on other sites More sharing options...
jhenley17 Posted September 23, 2016 Share Posted September 23, 2016 I'll have to find it, the pic was on my old phone and I'm not sure what I did with the paper. I've posted it here before, not sure where.I don't actually lose traction, that's just the feeling I get when it switches.Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted September 23, 2016 Share Posted September 23, 2016 13 hours ago, SlfAwre said: That last bit about harsh on/off throttle transition is exactly what I want to fix. My plan is to remove the air injection stuff first, maybe that will help w the popping but if I understand you correctly the fix for the on/off throttle is more involved and has to do with the fuel cut. My guess is the rapid bike stuff will fix that-as well as lean map overall? If I go that route, what is the risk to the cat that you mention? Well I am not sure exactly how the 8th gen's work, if the fuel cut operates the same and if the o2 sensors at set up the same.Fixing the overly lean factory mapping is simple enough and can be done with any power commander/ bazzaz/ rapid bike. If the o2 sensors work the same, you can fix the in and out of open and closed loop fuel injection with the power commander and o2 eliminators or rapid bike. If the fuel cut is the same, rapid bike is pretty much your only solution. Factory Lean mapping Factory narrow band o2 sensors Factory fuel cut Those are the three biggest culprits for the on/off throttle harshness and steady throttle surging. Link to comment Share on other sites More sharing options...
Rambler358 Posted September 24, 2016 Share Posted September 24, 2016 Well I am not sure exactly how the 8th gen's work, if the fuel cut operates the same and if the o2 sensors at set up the same. The 8th gens are definitely different from the previous VTECs. My '03 had a definite kick when the VTEC activated. When my 2015's VTEC kicks in, I really only notice a difference in sound. It definitely doesn't have the kick my '03 had. Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted September 24, 2016 Share Posted September 24, 2016 That could easily be just mapping related, with the o2 sensors and fuel cut remaining unchanged. Sent from my Nexus 6 using Tapatalk Link to comment Share on other sites More sharing options...
Rambler358 Posted September 24, 2016 Share Posted September 24, 2016 That could easily be just mapping related, with the o2 sensors and fuel cut remaining unchanged. Perhaps, but Honda did change the engine for the 8th gen model with a different torque curve and the point where VTEC kicks in. There's likely other changes as well. Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted September 24, 2016 Share Posted September 24, 2016 Yeah the compression ratio was bumped from 11.6 to 11.8:1, the intake cams were softened, the exhaust ports were reduced, the velocity stacks were lengthened and the header was redesigned. This with revised mapping can greatly effect the vtec transition. I haven't heard much about the actual vtec engagement point beyond, "it feels smoother". Sent from my Nexus 6 using Tapatalk Link to comment Share on other sites More sharing options...
jhenley17 Posted September 25, 2016 Share Posted September 25, 2016 Found my picture. This was just a dyno day, so nothing connected to the bike, hence the speed vs power instead of RPM vs power. Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
SHvar Posted September 25, 2016 Share Posted September 25, 2016 The fueling on the 8th gen is very accurate, if you make it run rich remove the catalytic converter or you will cause harm to it. The decel popping come from the air injection into the headers, not from being lean. Here is my dyno chart with the air fuel ratio at the bottom. Notice how smooth the VTEC transition is, this is with a Delkevic slip on, OEM air filter (the original filter from Honda over 2 years into use, it is still very very clean), and no other modifications to the bike aside from stomp grip, and a tail tidy. Link to comment Share on other sites More sharing options...
SlfAwre Posted September 25, 2016 Author Share Posted September 25, 2016 3 hours ago, SHvar said: The fueling on the 8th gen is very accurate, if you make it run rich remove the catalytic converter or you will cause harm to it. The decel popping come from the air injection into the headers, not from being lean. Here is my dyno chart with the air fuel ratio at the bottom. Notice how smooth the VTEC transition is, this is with a Delkevic slip on, OEM air filter (the original filter from Honda over 2 years into use, it is still very very clean), and no other modifications to the bike aside from stomp grip, and a tail tidy. Your bike is an 8th gen right? what do you mean when you say the fueling is very accurate? Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted September 26, 2016 Share Posted September 26, 2016 On 9/24/2016 at 8:53 PM, jhenley17 said: Found my picture. This was just a dyno day, so nothing connected to the bike, hence the speed vs power instead of RPM vs power. Sent from my iPhone using Tapatalk Man that is a nasty vtec crossover. Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted September 26, 2016 Share Posted September 26, 2016 On 9/24/2016 at 10:37 PM, SHvar said: The fueling on the 8th gen is very accurate, if you make it run rich remove the catalytic converter or you will cause harm to it. The decel popping come from the air injection into the headers, not from being lean. Here is my dyno chart with the air fuel ratio at the bottom. Notice how smooth the VTEC transition is, this is with a Delkevic slip on, OEM air filter (the original filter from Honda over 2 years into use, it is still very very clean), and no other modifications to the bike aside from stomp grip, and a tail tidy. Wow that is a really nice torque curve. Definitely enough to shut up even the biggest VTEC haters and fifth gen fan boys lol. The popping isn't just from the air injection, like I said earlier, even with block off plates, you will still get some popping, as the fuel cut plays a big part in the lean over run as well. On a side note, man that WOT AFR is super lean (but who knows how accurate it is, with the cat and Pair valves still in place). You could probably pull a little extra torque out of it by getting closer to 13.2:1, but like you said, not really a good idea to fiddle too much with the AFR until ditching all the emissions equipment. Looks like the VTEC crossover is still at about 6400 RPMs... Link to comment Share on other sites More sharing options...
jhenley17 Posted September 26, 2016 Share Posted September 26, 2016 Man that is a nasty vtec crossover. Yeah. I'm only going to be off one day every two weeks for the next few months, but when I get time, I'll be talking with the dealer's service department to see if this might be an issue covered by my warranty. Nobody else seems to have this issue and the other dyno chart posted looks very different. I'd like to see it run with the sniffer in the exhaust, but I'm not going to pay for it until I block the pair, gut the cat, and buy a PCV.Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted September 26, 2016 Share Posted September 26, 2016 I doubt honda will care about or even know how to fix your vtec crossover issue. I do think they will care about you modifying the bike though. Link to comment Share on other sites More sharing options...
Member Contributer Switchblade Posted September 26, 2016 Member Contributer Share Posted September 26, 2016 On 9/24/2016 at 8:53 PM, jhenley17 said: Found my picture. This was just a dyno day, so nothing connected to the bike, hence the speed vs power instead of RPM vs power. Sent from my iPhone using Tapatalk Looks like the throttle man chopped the throttle to me, that is the worst VTEC transition ever. Link to comment Share on other sites More sharing options...
jhenley17 Posted September 26, 2016 Share Posted September 26, 2016 Three consistent pulls to confirm my ass dyno readings. Actually, I expected just a flat spot more than a giant dip.Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted September 27, 2016 Share Posted September 27, 2016 looks like an untuned 6th gen lol Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted September 27, 2016 Share Posted September 27, 2016 Side note, not sure if I said it on this post or not, but Rapid Bike Racing > Power Commander 5 Link to comment Share on other sites More sharing options...
SlfAwre Posted September 27, 2016 Author Share Posted September 27, 2016 5 hours ago, CandyRedRC46 said: Side note, not sure if I said it on this post or not, but Rapid Bike Racing > Power Commander 5 That's my take after reading all this and some other stuff, but if I were to get one I'd have to de-cat the bike wouldn't I? Link to comment Share on other sites More sharing options...
CandyRedRC46 Posted September 27, 2016 Share Posted September 27, 2016 Just now, SlfAwre said: That's my take after reading all this and some other stuff, but if I were to get one I'd have to de-cat the bike wouldn't I? No not at all. The Rapid Bike Racing and Evo work great with a totally stock VFR800. Link to comment Share on other sites More sharing options...
chinook Posted September 27, 2016 Share Posted September 27, 2016 On 24/09/2016 at 6:09 AM, CandyRedRC46 said: Yeah the compression ratio was bumped from 11.6 to 11.8:1, the intake cams were softened, the exhaust ports were reduced, the velocity stacks were lengthened and the header was redesigned. This with revised mapping can greatly effect the vtec transition. I haven't heard much about the actual vtec engagement point beyond, "it feels smoother". Sent from my Nexus 6 using Tapatalk If you try really hard you can just detect a tiny glitch at part throttle as the system can't decide which way to go. Otherwse it switches from soft, silent two-valve running to a harder-edged booming four valve delivery between 6000 -7000rpm like a hot knife through butter. Link to comment Share on other sites More sharing options...
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