Can We Reduce Engine Braking?

[Alaskan]

Good luck and report back.

[Guest ohlarikd]

By the way, I don't claim to know what I am doing... I give this a 20% chance of working out...

[Rush2112]

By the way, I don't claim to know what I am doing... I give this a 20% chance of working out...

Good luck! I was going to suggest different throttle cam profiles to help with small throttle openings but I saw you already went there... just curious, what rpms are you running when you feel the excess engine braking? I thought you mentioned commuting, so are you lower in the rpm range? Also, do you have lightened rims like carbon fiber or any driveline changes to the bike?

[Guest ohlarikd]

Good luck! I was going to suggest different throttle cam profiles to help with small throttle openings but I saw you already went there... just curious, what rpms are you running when you feel the excess engine braking? I thought you mentioned commuting, so are you lower in the rpm range? Also, do you have lightened rims like carbon fiber or any driveline changes to the bike?

I have the throttle cam, but that does not apply when at 0 throttle and max engine braking.

It doesn't matter what RPM I am at, the engine braking feels the same. The effect is greater at lower speeds though since there is less forward momentum to counteract the braking. At high speeds, downshifting, it is not that noticeable. That is why I a say in normal speeds and traffic, that is when it is most bothersome.

Bike has 5700 miles on it, no mods. It has always felt this way.

[Guest ohlarikd]

So I took things apart and wanted to study how this all works. I can see that there are some holes to let air in at Idle, and that they are controlled by a solenoid. Seems like they are pulled more open when cold (I could hear a loud rush of intake air initially), but as it warms, I think they closed at some point because now it is quiet. If I manually open them I can get the loud rush of air again, and a corresponding RPM increase.

I am wondering if I should go to the dealer and get these adjusted or at least get their opinion on this engine braking phenomenon. Maybe there is a real issue here (Sorry 2thdr... jumped down your throat, was in a crappy mood at that point...). Maybe its just a bad adjustment? I don't know how to accurately adjust these...

[2thdr]

I'd like to see a poll and see how many folks think this is an issue. I've been active around here for 3 years and this is the first thread I've seen on the complaint...

Not interested in a poll. If I think its a problem, then its a problem. If someone does not agree, then they can move along.

No problem...just like I said, I haven't seen anyone mention this specifically in the three years I've been hanging around here. Not trying to discount your assessment and how it relates to YOUR bike and YOUR riding. I have been luckily blessed (or bliss through ignorance...LOL) with a stock bike (except for Erion Racing cans) that I think runs perfectly. Of course I have never owned a full on sport bike... I am just grateful that my fueling seems consistent and I haven't experienced the "surging" issue that many here have complained about. I wonder if in fact yours is a surging issue...?

[Guest ohlarikd]

No problem...just like I said, I haven't seen anyone mention this specifically in the three years I've been hanging around here. Not trying to discount your assessment and how it relates to YOUR bike and YOUR riding. I have been luckily blessed (or bliss through ignorance...LOL) with a stock bike (except for Erion Racing cans) that I think runs perfectly. Of course I have never owned a full on sport bike... I am just grateful that my fueling seems consistent and I haven't experienced the "surging" issue that many here have complained about. I wonder if in fact yours is a surging issue...?

Yeah sorry man, I don't like to be a jerk like that.

I am thinking to get the bike checked out and adjusted first before I go nuts trying to fix this. The more I stare at it, the more I think I will need some massive fuel-remapping if the butterflies are open more at all positions. If I don't, it will run lean. Unless the ECU can correct it? But then what is the Dynojet Autotune for?

[Alaskan]

ohlarikid, why don't you test ride another member's VFR? Then you will see whether this is an issue with your VFR or whether it is typical of the model.

[Guest ohlarikd]

ohlarikid, why don't you test ride another member's VFR? Then you will see whether this is an issue with your VFR or whether it is typical of the model.

That would be great but I don't know anyone near me. That would be incredibly helpful. I am almost wondering if I have atypical driveline lash, which is really bad as well...

[2thdr]

ohlarikid, why don't you test ride another member's VFR? Then you will see whether this is an issue with your VFR or whether it is typical of the model.

That would be great but I don't know anyone near me. That would be incredibly helpful. I am almost wondering if I have atypical driveline lash, which is really bad as well...

http://www.vfrdiscussion.com/forum/index.php/membermap/

[NakedViffer]

Your engine braking is harder at lower RPM than higher? Are you kidding me? This thread is starting to make my face hurt.

[Guest ohlarikd]

Your engine braking is harder at lower RPM than higher? Are you kidding me? This thread is starting to make my face hurt.

I know that is obvious, the question was asked. It feels like throwing out a parachute, unlike my R1, GSXR750, CBR600, YZF1000, 525 SMR...

Edited May 4, 2013 by ohlarikd

[dawson]

Mine decelerates hard when I roll off the throttle for slow turns. More noticable in second and first gear, as in enough to snap the helmet forward. Makes it impossible to ride smoothly through a parking lot without feathering the clutch. On mine it's due to the lousy stock mapping being way too rich rather than physical engine design. That can be fixed with a power commander, I just have to find the time to do it properly.

What's your fuel economy like? I get high 20s when riding in town. If you're around there it could be an indication that you're in a similar situation.

[Guest ohlarikd]

Mine decelerates hard when I roll off the throttle for slow turns. More noticable in second and first gear, as in enough to snap the helmet forward. Makes it impossible to ride smoothly through a parking lot without feathering the clutch. On mine it's due to the lousy stock mapping being way too rich rather than physical engine design. That can be fixed with a power commander, I just have to find the time to do it properly.

What's your fuel economy like? I get high 20s when riding in town. If you're around there it could be an indication that you're in a similar situation.

I have a Power Commander V. That will/did fix acceleration and on the gas, solved the VTEC transition. It won't help at all with the hard deceleration (glad someone else feels this - my head snaps forward too, unlike my other bikes). I get 40 or so MPG, so that seems ok.

[Guest ohlarikd]

Ok - PARTIAL Success. I adjusted those little air holes to allow more air when warmed up. I could tell when I revved the engine that it was not crashing down to 1500 RPM anymore; it would come down slower, more 'normal' to my expectations. Maybe too slow. I went for a ride and the engine braking was actually too far in the direction of NOT enough now! So I know those adjusters have a great effect, and are probably not adjusted correctly when I got the bike.

Also - when I put it into first, it jumps to 4000 RPM until I goose the throttle then it drops. Not sure why. One of the four adjusters was not like the other... maybe that one has some effect there. Anyway, now that I see that there is HOPE here, I am going to to talk to the Honda service guy and ask about these adjusters.

Guess that will happen Tuesday when they open. There is definitely something wrong the last two years, and I guess it is thankfully not 'the way it is'.

Thanks for the patience guys!

[CandyRedRC46]

Ok - PARTIAL Success. I adjusted those little air holes to allow more air when warmed up. I could tell when I revved the engine that it was not crashing down to 1500 RPM anymore; it would come down slower, more 'normal' to my expectations. Maybe too slow. I went for a ride and the engine braking was actually too far in the direction of NOT enough now! So I know those adjusters have a great effect, and are probably not adjusted correctly when I got the bike.

Also - when I put it into first, it jumps to 4000 RPM until I goose the throttle then it drops. Not sure why. One of the four adjusters was not like the other... maybe that one has some effect there. Anyway, now that I see that there is HOPE here, I am going to to talk to the Honda service guy and ask about these adjusters.

Guess that will happen Tuesday when they open. There is definitely something wrong the last two years, and I guess it is thankfully not 'the way it is'.

Thanks for the patience guys!

Oh man why did you mess with the starter valves? those are for the warm up cycle (high idle, wax unit)

Anyways those aren't your problem, but it may be a good idea to have the starter valves synced by honda though, especially after messing with them.

What your problem is and where you should be focusing is the fuel cut. Every new bike since the last 10 years or so has a fuel cut at over 4500 rpms and 0% throttle for emissions purposes. Basically when you are decelerating hard there is no fuel being sprayed into your engine. It is more or less the same as dropping a few gears and hitting the kill switch.

You need to look into this:

http://www.ivansperformanceproducts.com/2006fz1.htm

And I will answer your question right now, no a power commander will not fix this, as any percent of zero is still zero, you will not be able to add gas in the 0% throttle column.

You should start emailing Ivan right now.

[CandyRedRC46]

http://www.bcsportbikes.com/forum/showthread.php/48472-VFR-VTEC-Must-Read-Throttle-Problems/page2

[Guest ohlarikd]

Ok - PARTIAL Success. I adjusted those little air holes to allow more air when warmed up. I could tell when I revved the engine that it was not crashing down to 1500 RPM anymore; it would come down slower, more 'normal' to my expectations. Maybe too slow. I went for a ride and the engine braking was actually too far in the direction of NOT enough now! So I know those adjusters have a great effect, and are probably not adjusted correctly when I got the bike.

Also - when I put it into first, it jumps to 4000 RPM until I goose the throttle then it drops. Not sure why. One of the four adjusters was not like the other... maybe that one has some effect there. Anyway, now that I see that there is HOPE here, I am going to to talk to the Honda service guy and ask about these adjusters.

Guess that will happen Tuesday when they open. There is definitely something wrong the last two years, and I guess it is thankfully not 'the way it is'.

Thanks for the patience guys!

Oh man why did you mess with the starter valves? those are for the warm up cycle (high idle, wax unit)

Anyways those aren't your problem, but it may be a good idea to have the starter valves synced by honda though, especially after messing with them.

What your problem is and where you should be focusing is the fuel cut. Every new bike since the last 10 years or so has a fuel cut at over 4500 rpms and 0% throttle for emissions purposes. Basically when you are decelerating hard there is no fuel being sprayed into your engine. It is more or less the same as dropping a few gears and hitting the kill switch.

You need to look into this:

http://www.ivansperformanceproducts.com/2006fz1.htm

And I will answer your question right now, no a power commander will not fix this, as any percent of zero is still zero, you will not be able to add gas in the 0% throttle column.

You should start emailing Ivan right now.

Interesting CandyRed... I have never heard of complete fuel cut off in this VFR, and it doesn't exactly feel like that is happening. But anyway, there is no kit for the VFR from Ivan. After I get these valves checked out by Honda, I will see how the bike feels and maybe email Ivan for some advice.

Messing with those air holes was a 'no harm done' situation as the bike was already difficult to ride and will eventually head to Honda. The holes have to allow some air in when idling or else the engine would choke when the throttle plates are fully closed. I can put my fingers over the holes and kill the engine. Since I had this 'too much vacuum' theory, these holes seem to be the ticket, and they were adjustable. I went too far to make sure I could see an effect, and I certainly DID. I went too extreme and have almost no engine braking. The herky jerkiness went away as well and dare I say, I actually ENJOYED riding it! There is that 4000 RPM issue, but I think the EFI may be confused. Just guessing... wish I had a service manual - may look for one.

I will go to the dealer and discuss the issue and what I did, and get this thing tuned up. Since it only had 4500 miles on it when I got it, I didn't imagine there would be any tuning issues, but who knows what the original owner did, or maybe the original dealer was not trained properly.

[CandyRedRC46]

i can not wrap my head around why you opened up the starter valves instead of just cranking up the idle screw on the side of the bike.

anyways there is a pdf of the service manual in the downloads section of the site.

http://www.vfrdiscussion.com/forum/index.php/files/category/2-owners-manuals-and-other/

[Guest ohlarikd]

http://www.bcsportbikes.com/forum/showthread.php/48472-VFR-VTEC-Must-Read-Throttle-Problems/page2

Just read the whole thing. They seem to be focused on acceleration and throttle response. I think I have zero issues with that now with the PC5 and the Cozy map. I don't even think about that.

The decel engine braking is never discussed, but they had the SV synced. I need to do that . First if they are synced, there is a main adjustment that can adjust all 4 at the same time. I can reduce and increase the amount of air being pulled into the cylinders at 0% throttle. But I totally guessed at the syncing part. Clearly, I need to get a manometer or bring it to dealer.

Thanks for the tips and leads! Keep 'em coming!

i can not wrap my head around why you opened up the starter valves instead of just cranking up the idle screw on the side of the bike.

anyways there is a pdf of the service manual in the downloads section of the site.

http://www.vfrdiscussion.com/forum/index.php/files/category/2-owners-manuals-and-other/

Downloading manual - thanks!! I have messed with Idle. Does it connect to the starter valves? I need to see where that cable goes and what it is actually doing, to see if it will have an effect on engine braking. The Idle seemed perfect, and I don't recall ever messing with an idle and seeing an effect on engine braking - but then again, I've never had to really do this. Like I said, I never claimed that I had all the answers or was doing the right thing - I am learning here in an effort to fix an issue. Everything can be adjusted back or redone, no big deal to me.

Anyway, I will take it apart again and study this in more detail. Also, I am missing 1 velocity stack. The screw stripped of course (as nothing ever goes smoothly), so I had to hack the stack apart to get my dremel on the screw to remove it. Ordered new ones.

Let me stress again - everything I am doing, even if its guesswork, can be put back. I appreciate the advice and guidance here. I make mistakes but who cares? I am just fiddling!

[Noobtastic14]

I stopped reading when I realize you are an experienced rider that cannot control engine braking. So much so, that you broke into the engine to fix it.

-Drew

[Guest ohlarikd]

I stopped reading when I realize you are an experienced rider that cannot control engine braking. So much so, that you broke into the engine to fix it.

-Drew

You are an idiot. Did you read anything. The bike has a problem.

[Rush2112]

Good luck! I was going to suggest different throttle cam profiles to help with small throttle openings but I saw you already went there... just curious, what rpms are you running when you feel the excess engine braking? I thought you mentioned commuting, so are you lower in the rpm range? Also, do you have lightened rims like carbon fiber or any driveline changes to the bike?

I have the throttle cam, but that does not apply when at 0 throttle and max engine braking.

It doesn't matter what RPM I am at, the engine braking feels the same. The effect is greater at lower speeds though since there is less forward momentum to counteract the braking. At high speeds, downshifting, it is not that noticeable. That is why I a say in normal speeds and traffic, that is when it is most bothersome.

Bike has 5700 miles on it, no mods. It has always felt this way.

Ok, I understand what your saying... my bike doesn't exhibit severe engine braking either at higher rpms, I figure it is due to all the rotating mass momentum. I was using a similar chain of thought when I asked about lightweight rims... less mass, less momentum so greater engine braking.

The throttle cam profile I was thinking if you had something like a G2 it might help to gently crack open the throttle bodies a little easier.

[Guest ohlarikd]

Good luck! I was going to suggest different throttle cam profiles to help with small throttle openings but I saw you already went there... just curious, what rpms are you running when you feel the excess engine braking? I thought you mentioned commuting, so are you lower in the rpm range? Also, do you have lightened rims like carbon fiber or any driveline changes to the bike?

I have the throttle cam, but that does not apply when at 0 throttle and max engine braking.

It doesn't matter what RPM I am at, the engine braking feels the same. The effect is greater at lower speeds though since there is less forward momentum to counteract the braking. At high speeds, downshifting, it is not that noticeable. That is why I a say in normal speeds and traffic, that is when it is most bothersome.

Bike has 5700 miles on it, no mods. It has always felt this way.

Ok, I understand what your saying... my bike doesn't exhibit severe engine braking either at higher rpms, I figure it is due to all the rotating mass momentum. I was using a similar chain of thought when I asked about lightweight rims... less mass, less momentum so greater engine braking.

The throttle cam profile I was thinking if you had something like a G2 it might help to gently crack open the throttle bodies a little easier.

That's the name, the G2. That greatly helped the low speed stuff. So I have no real issue with touchy throttles or hesitations.

I know the severe engine braking is some issue with the previous owners tuning since I all but eliminated it with an adjustment. It must be off from what the rest of you guys are used to. Will get it to a dealer.

[Rush2112]

Good luck! I was going to suggest different throttle cam profiles to help with small throttle openings but I saw you already went there... just curious, what rpms are you running when you feel the excess engine braking? I thought you mentioned commuting, so are you lower in the rpm range? Also, do you have lightened rims like carbon fiber or any driveline changes to the bike?

I have the throttle cam, but that does not apply when at 0 throttle and max engine braking.

It doesn't matter what RPM I am at, the engine braking feels the same. The effect is greater at lower speeds though since there is less forward momentum to counteract the braking. At high speeds, downshifting, it is not that noticeable. That is why I a say in normal speeds and traffic, that is when it is most bothersome.

Bike has 5700 miles on it, no mods. It has always felt this way.

Ok, I understand what your saying... my bike doesn't exhibit severe engine braking either at higher rpms, I figure it is due to all the rotating mass momentum. I was using a similar chain of thought when I asked about lightweight rims... less mass, less momentum so greater engine braking.

The throttle cam profile I was thinking if you had something like a G2 it might help to gently crack open the throttle bodies a little easier.

That's the name, the G2. That greatly helped the low speed stuff. So I have no real issue with touchy throttles or hesitations.

I know the severe engine braking is some issue with the previous owners tuning since I all but eliminated it with an adjustment. It must be off from what the rest of you guys are used to. Will get it to a dealer.

Synching the starter valves and setting the idle correctly will definitely help the engine run smoother and I hope it corrects what you are experiencing... Summer is coming, get it right and get riding