PAIR valve blockoff

I can't say exactly how the Honda ECU programming works. The only way to know exactly when the PAIR system is operating would be to get the programming info from Honda or put a light across the solenoid wiring and watch it when riding. I think I can say that Honda's engine guys are not so stupid as to dump air into the exhaust and then expect the O2 sensor to read correctly. The car's I am familiar with only used the air injection when cold and switched it off at a certain temperature. I have hear that others used it during deceleration The O2 sensor is used to optimize the A/F ratio for low emissions during steady state operation. It is probably not looked at at all during WOT operation and when the throttle position is changing constantly like running down a tight twisty road.

As far as compensation for altitude, I can't say specifically what this bike uses but all modern EFI set ups use some sort of air sensor. Usually a mass airflow sensor. This measures the actual number of air molecules going through it and as such is not affected by altitude. Some older systems used a manifold absolute pressure gauge that inferred the same information but perhaps not as accurately. So all modern EFI systems compensate for altitude automatically. It is one of the cool things they do along with excellent cold starts.

A power commander does not replace your ECU's fuel commands. It inserts in series (in line with) the commands to your fuel injectors and either adds or subtracts from the length of the fuel pulse. So your ECU is still controlling the the fuel but the PC is saying "whatever Honda says add a bit more or subtract a bit. Typically these are used with dummy O2 sensors that tell your ECU that all is fine all the time. The ECU has no way to compensate for a free flowing exhaust system during all the times when it isn't looking at the O2 sensor so a PC is the way to go to get your bike to run right with that new muffler or header. A word of caution. Your catalytic converter is designed to last a good long time when used with the factory fuel map and O2 sensor feedback. If you are running significantly richer settings it will probably fail much sooner. How much sooner depends on how rich.

All these theories about how the PAIR makes the bike run rich fly completely in the face of other observations that the bike surges and lurches because the fuel map is too lean. It is also antithetical to the purpose of the PAIR system in the first place which is to reduce emissions. If it screwed up the A/F ratio in the rich direction the bike wouldn't pass the emissions tests.

My 06 does not do anything the I would call surging. The on/off throttle transition can be a bit abrupt but a sensitive throttle hand can smooth it out. There are a few funny little non linearities/flat spots at mid RPM and very light throttle settings. They aren't really troublesome, just kind of strange. Open the throttle a bit more and everything is fine. Steady state cruising at any speed above about 20 mph is fine. Full throttle acceleration at any rpm above 2500 is perfectly fine. Right now there is nothing that makes me want to go down the tweaking path and I can't say that about all of the carbureted bikes I have owned. Personally I am very encouraged that this bike can be this green and run this good. I was afraid the new EPA requirements were going to cause all the bikes to run like crap for 10 years until they figured it out like what happened with cars. I guess they are applying those lessons well.

Do you think a guy that buys a 500HP Ferrari takes it home and guts the catalytic converter in search of more power?

My state does 2 year emissions tests on cars. I can only imagine that bikes will someday follow.

 

Personally I am relieved at removeing the Cat . we do Not have such strict Laws here regarding convertors , and the cat is definitely an air-flow restriction , I Know this because I am not a bike fundi , learnt to feel the power on this bike , and after removing the cat the bike now front-end wheelies , and I do Not wheelie On purpose , so the restriction is there .

As for the Vince pipes Im fitting , I am sad sad sad to be Losing that clean-cut look I have with the stock pipes , the amount of money being spent on a performance pipe Boggles the mind , when , in fact , it is NOT a performance bike . I just hope the Ducati-like sound is worth all the money ( it wont - I can already feel me getting the jitters about spending so much )

I ordered the ally pipes . But I really think that apart from the new"beat" , pretty much pointless ? But more of that V4 sound emerging from the pipes..... Yes please .

 

Gutted

Hi all

I was reading all your stories and suddenly got sick of all the better power and stuff, so this morning (Monday 3rd of September 2007) I took my bike to Noise Boise and they gutted it for me. It took them longer than an hour as the two "whatevers" were spotted in the inside.

I was charged R150 so I paid the good man R200 for a job well done.

Sounds great, although at first I thought there was a forgotten hole somewhere for the sound reminded me when my car needed a new pipe!

I grew used to it very fast as the sound emitted after the V-tec kicks in is awesome!

It feels more powerful, but it may be only in my head. Hope not.

Go and do it, it sounds, well different and great!:first:

 

Try THIS then ..... Heh heh Heh .... Im screwed now , The bug has bitten .




Gurgle Gurgle ....



Trust me , this change to One's ear is as radical as Your Daughter having Brown Hair in the Moring , then coming home and finding sh'e dyed it Shocking Rescue-chopper Orange ..........

 

Pair Valve Mod

Hi

I just did the Pair Valve Mod and had already done the Cat.

The bike seems better and definately smoother in corners going through the V-Tech RPM. Nice, now I just need performance pipes.

Will test it more tomorrow on a breakfast run against one of those ZX10Rs.

Later

 

My 2007 Ducati ST3 had the same surging/stalling problems as your Gen6 Interceptors. Same fix. I disconnected the vacuum hose from the airbox. But you will notice a 'gasier' smell as one rider put it. That's because after you do that you need to have the throttle bodies adjusted. And the TPS (throttle position sensor) as well. These newer emmision standards have led manufacturers to use a closed loop system.

Hell, before I brought it in for the TB's to be adjusted I was getting about 115 miles on a 5.8 gallon tank! Bike ran great! Just rich as all hell! The TB's needed to be leaned out of course, hence the gas smell when you plug the valve; bike runs too rich. Watch your gas mileage and let me know if you can't tell a difference. Mine was way drastic because they had the bike running way rich from the get-go trying to fix the lean problem. But there's only so much adjusting you can do with a fixed ECU. The best thing you can do is get a power commander and have it tuned right, but the cheap fix is a pretty damn good one. Gone are the days when the conpanies GAVE you an adjustable ECU. Now they want you to buy the aftermarket from them instead of giving you a good product from the start. Such a pity.

Stan

 

Ok, I am new to this forum, and thinking about buying a 2007 Interceptor. I am reading about this surging issue a bit and want more info on it.

I have a 2007 Ducati ST3 right now and they have this issue, but only this year because they are adhering to Euro3 emission standards now. The 2006 and earlier do not have this problem, because the fuel injection is not a closed loop system. Same type of fix though. I took off a hose connected to the airbox. Bike runs fine now.

My question I guess is this:

Are all Gen6 Interceptors subject to this surging and hence a subsequent PAIR block mod, or just a few years in this generation?

I ask this, because I can get a great deal on a brand new 2005 Interceptor if the PAIR block is not an issue for that model year. I guess I am asking at what year did they implement an oxygen sensor into the exhaust system on this model Honda? That would indicate a closed loop system.

I have a feeling it's a V-twin and opposed cylinder issue (BMW). Although my 650 Vstrom rode smooth as glass, it was a 2005 model. I have heard many BMW owners complain about surging issues, as well as the newer V-twin owners. I think it's because of the natural pulsing that these engines make. That, and the addition of the oxygen sensor trying to starve the engine at steady speeds. Inline fours are smoother running, no pulsing issues as far as I have read.

Stan

 

On off throttle transition harshness can be adjusted... the TPS (throttle position sensor) along with adjusting the throttle cable tension can eliminate the jerkiness of that transition. There is nothing MORE dangerous than a bike that has a harsh transition! You need a smooth transition when attacking corners under acceleration! Harsh transition only makes a rider afraid to take a corner at speed. Even if you THINK you have a feather touch on your throttle I dare you to claim so when you hit a bump at speed in a turn. If your throttle is not smooth you are in for a shock. Combine a harsh throttle response with a bike tuned lean and you are asking for trouble. Not a very confidence inspiring ride either, trust me. I hated my Ducati when I first got it, until I adjusted the TPS and the cable, and then disconected the vacuum hose to the airbox, THEN had the shop resynch my throttle bodies and remap the ECU! They actually had to LEAN the bike out!

The bike is not very inspiring when you have to take even a normal cornering issue to mind and downshift so your revs are up in the 5-6k range around town. A bike should pull with confidence from 2500 rpm, as you mention, not choke and spit (the bike itself may shudder a bit maybe because you're so low, but not hesitate!).

This surging is NOT an issue under acceleration above 3krpm, it IS an issue under, as you call it. 'steady state cruising' THAT'S when the O2 sensor tells the ECU to run lean, NOT when accelerating. When you accelerate the paranmeters regarding the relationship of the O2 sensor to the ECU have a lot more latitude, and basically the vacuum shuts down the O2 sensor input to the ECU when a certain vacuum pressure is reached under hard acceleration. Your flat spots that you notice are mostly when you are under light acceleration, and I claim that to be gearing mostly, not your ECU starving your bike while accelerating. The flat spot's just more noticeable if you are easing your bike up through the rpms than it is under hard acceleration.

When you go to get the emissions tested they hook a hose to your exhaust under IDLE. That's why they put that oxygen sensor there, to choke the bike while being tested. Unfortunately, it chokes the bike under a lot of riding situations as well, which makes a rider uneasy/unsure of what his bike's response is going to be to various throttle input acceleration-wise. THAT'S the issue.

All your techno-babble is great, but in real world situations the rubber meets the road, not a spec sheet. In my 30+ years of riding these new EPA controls are a sad state of affairs for modern motorbikes. Most people go aftermarket with exhaust and ECU to correct the 'breathing' and flat spot issues. I am willing to bet Honda sells a performance upgrade, as did my Ducati for my ST3. But why should you have to spend another $1,200.00 or so to make a bike run right when it should already? I hear so many doing the same things to their Interceptors as my cohorts are doing to their Ducatis; i.e. replacing the exhaust, ECU, remapping, and K&N air filters (along with a more aerated airbox). It's the same bloody issue across the board.

Stan

 

Wortman gave me a little insight as to how the system works , and I must say that I was quite surprised to find it only works on Decel. I have thus far not re-connected it as I was planning to , but his theory makes sense .
Still , the bike suffers no negligable Loss of power etc , so I have stuck to my guns about the pairVelave .
One thing I Do disagree with , is the statement of Not removing the Cat .

this is My first bike . I ran the bike for 3 months With Cat . then I removed it . The bike Lifts it's nose now ,and no doubt in my mind this is from the Cat removal .The cat is a physical mechanical Barrier no matter which way one looks at it . I doubt there are Cats on F1 Cars ? i understand about the emissions , but superbikes Dont have Cats do they ? And this Bike is 10hp short of real power anyway , so I feel the Cat and Pair are worthwhile . The stock pipes are heavy , but thats it . Removing them was chasing that duke sound we al llove , but it is Not an in-expensive execrcise , let me Assure you .

I Picked up this Model For an Absolute bargain after the owner traded it in for a Rincon Quad - I though he was nuts , as I already have a quad !! So I bought it at trade-in value , with only 1400 km on the clock. nothign wrong with that ...

 

Hmmmm... is that what it's all about? Making a Honda sound like a Ducati? By the way, the word is Duc (pronounced DUCK, not Duke) for anyone that actually owns one.

What ever happened to buying a bike because you love it for what it is? I love my Ducati ST3 for what it is. If I wanted a racier model I would own a 1098. I like the Interceptor for what it is too. I wouldn't change either from stock, even though everyone seems to think the first thing you do to any bike is change the cans. Gotta sound bad-ass, right? Make it breath better, right. Horse crap. People don't need to hear you coming. You need to make sure you know where THEY are. Loud pipes are no match for a keen sense of awareness of your total surroundings. You want a more throaty sound from your stock configuration? Drill out a few quarter size holes in your airbox and use a K&N air filter set-up. Air flow is stifled first at the airbox, not the exhaust.

Next is changing the sprockets, then the suspension. Why stop there? They make Nitrous kits too ya know. What most of you newbies don't even understand is the fact that you're gonna spend all that money modifying your bike, only to want another newer badder-ass model when it comes out. Such a waste of money. And you're not gonna get anything out of it come trade-in time either. That's if it makes it to trade-in and not the scrap heap first. I look at a bike like that and figure the previous owner ran the piss out of it, so why should I want it? Give me a stock bike that runs the way it's supposed to and I am a happy camper.

If you want a race bike, then save up, buy it, and bring it to track days.Grow up some of you. If your goal is to bring the nose of your bike into the air, just make sure you know what to do when it comes down. First bike an Interceptor? Hope you have great medical insurance.

 

mmm in Australia we pronounce it Dewkatti ?? :wink:

 

Hmmmmm... dewkatti, but is that cotti, caty, or katie?

 

Crikey!!

Catty is the best lol
Pronounced with an Aussie drawl :biggrin:

But I prefer VEE EFF ARR !!!

 

DUck - HEH ???

Bike mags refer to the duke , or the super-duke . Duck ???? Nahh ... I prefer duke , but thank you for the grammar Lesson !

Italians say -Doocatti ,

Grief , I've never given as much though to the damn SAYING of the word other than the Mf SOUND it's engines make !

"Duhh".....catti Nope .

"Duke" it stays with me , even though we dont Say it like that here , as in Dukecatti , we say Du(oo)Catti . Ducatti .

You got me going in Circles Now .

 

Yes. First Bike . a VFR 800. An INterceptor - But ONly NAMED so In AMERICA - Ordinarily Known as a VFR 800 - from the time I was 7 , this bike was a Vfr750- it's only HERE on the forum I first started hearing it being referred to as INterceptor . but Perhaps thats because there are always specail Models made for America ....

First Bike . Yes . I have not owned Any other Bikes Before this one - so that would make it the first one , Correct ???? This bike is Not Bad-assed at all - so what you're saying is that if I buy a hand-gun I should start with a Daisy ?? oh PLEASE - with a little intelligence and common sense , you can own a stronger bike without becoming a victim . do you HONESTLY think I'd have purchased it if I didnt know what I was buying ?? huh ???

Superbike- No thank you . Pipes Don't turn a tourer into a super bike . It simply Releases more of this Particular bikes Character , which is exactly what I am after . That v4 Engine is amazing .

Nobody mentioned ANYTHING about track days , mr. Stoner. And let me Assure you , that for ANY Mods we need to be done , I only need to go and Look as far as some U.s Site , and it's been DONE . ffs , I have to list my TRAILER as a MOdification in my Mod list under some of the US Quad sites,for Pete;s sakes , because the Guys on the Site have Mods longer than the first chapter in the bIble , so no Need to preach to ME cousin - look in your yard first .I agree with you about getting nothing in Return come trade in time , but seriously , that is one of the most Stereo-typical Posts I have read to date - you automatically assume that I Ride hard, Love bling bling ,and fall into the same category in your mind as the Dufus Modder wanting to trade his bike in . Newbie I may be , But I have my Own sense of Respect for others , as well as Motor-bikes.And at 35 , I certainly waited long enough until I had enough life-experience until I decided to buy something that could potentially Kill Me in the wrong hands or if Not handled with enough respect . to imply that every newbie to This forum does not have Intelligence, or at least Enough intelligence to handle a bike with common sense is absurd .

thansk for the positive outlook though.Some moral support you are. Scrap heap.

Air-flow stifled at the Air-box First - Quite correct . Only reason I did the Exhaust mod was to release a stronger note from it .These bikes are awfully quiet , and I mentioned that even though I did the mod , I would still Miss the standard exhausts .

You speak with Way too much Assumption .

 

No, I speak with the knowledge and wisdom of someone older than you. Been there, done that, seen that, heard it all before and visited my friends in the hospital and at funerals. Been riding since you were born, but take my words with a grain of salt if you wish.

I am glad you are so mature. Welcome to your second childhood. Funny method you have of showing your own way of respect for others by lashing out at them. Me? A stoner. That made me laugh really hard, thank you.

The Leo Vince is a great mod, but looking at your pics I have to wonder if it's going to discolor your turn signals and tail light lenses, or even warp them with the loss of the heat shielding. I hope not. Probably not, otherwise they would not be on the market without the proper testing, right? Like the VFR800. Awesome bike, perfect in every way, right?... except that little surging problem.

Stan

 

To each his own.

 

i agree .

Wabbit , I hear you . Experience or No , you just cannot say that because the man's changing pipes , it's purely for speed .
I thought about it afters : the pipes pure and simply , build character to the bike . Nothing more , Nothing Less .
I took her for a spin into town , and the new-found noise is a little unsettling to say the least , but as Jabba says , to each his own , and I like it .

The pipes stay alarmingly Cool , I would imagine this to be a result of them being so through-pipe though , no real design issue .Tested , yes . Checked that on the italian site , before I thought of doing the deal .

Make No mistake , I have wanted one since I was a kiddie . Always stood outside the coffe-shop , wondering what It was the guy did to afford one . Lucky sod .
I am lucky enough to own one now , and regularly pinch myself when coming out of the Mall , to find my Own Vfr standing there waiting for me in the lot .
Nice .... an' now it has barkers on too .

IF the Indicators melt I will post you pics so you can gloat over my ignorance .
here 's hoping that never happens though . I'll sh!t in my shorts if it does ! .

I have yet to hear of (like 2Cbr owners I know ) Vfr owners selling the bike due to issues of lower back pan when cruising at sane speeds.

I Love this bike too much to ever go for a super . I Know of no other bike that I feel as comfortable On .
Surging , wortman actually posted a valid post making me think twice about making any further mods to smooth things out . Part and parcel of owning a Vfr , Thats how I have grown to accept it . A little unsettling at first , but I'm prepared to live with it . The pluses far outweigh the negatives of the bike . Agreed ?

All-round , The bike is a beaut .

 

haha ok ok. this is the deal. As far as im concerned, and I am a young guy, so far be it from me to sound mature, but:
Pair Valve mod- did it, easy way blocking airbox nozzle with electrical tape, replacing hose, seemed to help surging, didnt hurt anything I can see.
Cat Gutting- cool, no cat has to equal better flow, IMO, im leavin it though.
Exhaust- make it sound cool, probably no major HP changes, soooooon...

Long story short, its a fun bike, we all like to go fast sometimes, if winding the VFR into V-tech doesnt get your blood going, then check your pulse! But yes, the other side of the coin is also worth mentioning, it isnt a ducatti, but hey, mind as well have fun, and if that means modding or not modding, more power to ya!

ooh and I just installed HID Xenons and machined my clip ons to get a better handlebar angle and those are two GREAT mods. Might not make it faster, but more comfortable and safer (and cooler lookin!) definitely

lets keep the tempers cooler than the tires gents!

 

Def -

I wouldn't gloat over your pipes melting your signals. That would suck. They just look to be really close to them. I'm glad they seem to be running cool.

I never raised the question of backache. Never had trouble with my back even on real crotch rockets over a few hundred miles. It's usually the butt that complains way before the back! My Ducati ST3 is all day comfortable. But I am after more than even that. at a sticker of $13,000 it's not a bad bike... till you hear what it cost for the 6,500 mile tune-up! $1,200 is a bit steep for me when you consider I ride daily, rain or shine, and I put 10,700 miles on it at 8 months old. That's without any major touring yet! I have not taken it in for it's scheduled service. If you ask me the only think needs adjusting on it is belt tightening, and that's just to make sure they're taught. I have no doubt they are still in good shape. But as you can see, if I put that kind of mileage on a bike, it would be in for service more than once a year, and it's just not worth it.

That's why I am turning to possibly buying the 2007 Anniversary model this weekend. I was at the dealership Saturday and told the salesman I will pay $9199 for the bike, plus tax, etc, and my trade of the Ducati, and I do want the bags of course. I said I'll give them $9,500 OTD (out the door). I had the salesman pull the maintenance timetable and costs. It was minimal. I like that.

The salesman called me this afternoon at work and said his manager is willing but wants to see my bike. I think it's a done deal really. If I do buy it I plan to ride it for a bit and see how severe the surging issue is. The surging issue on my Ducati was VERY severe. So much so that you were always wondering if it was going to jump when you were trying to take a simple turn in the city. I found myself always in a lower gear keeping the revs up so it would be predictable going into a turn. I finally had the dealership fix that problem, in a similar manner that you all are describing on the VFR. They disconnected a hose on the air box and it runs like it should. But they didn't do a thing till I got Ducati North America involved.

As far as exhaust notes, I prefer stock. I take long rides and I get tired of that 'sweet after market tone' on the highway. I prefer to listen to music instead. From what I've read about this bike it's stock set-up is so quiet that you wonder if it's on at a stoplight. I've ground the starter on a few bikes that were like that! My stock Ducati is that quiet.

Actually, I'd probably drill a few holes in the air box and do the K&N set-up after a bit. I like hearing the motor growl, not the pipes, and once you level off the motor goes back to being quiet, but it does breath better with a more aerated box. Most of the time you have to resynch the TBs when you do that, but it's not a big deal.

Stan