Attempt at consensus of VTEC fixes/improvements

From researching the UK site and analyzing this until my eyes are This thread is an attempt to list what people have done, and what has and has NOT worked to smooth out power delivery. I listed a thread over there as some of these mods seem to be getting redundant with the system.

Fortunately my bike 04' with Staintunes/ stock, doesn't have the catastrophic problems that some have had, but I cannot hold steady throttle at 5k and the 7k boost is what it is. Being a perfectionist/bike nut I can't just leave it. First FI bike of 9 and boy Honda's refusal to acknowledge problems is disheartening at best.
The purpose of the thread is to educate everyone and try not to spend the 600-700$ for a full tune.

Thanks upfront and please only respond if you own this machine or have something positive or meaningful to add to the discussion. Mere gloating of gear driven cams and 5th Gen supremacy :blah: does not cut it please. If all you guys had the bike problem I doubt if I would rub it in your face, not my style as a helpful rider. We know you don't like the new bike. Otherwise you would own one. I bought the new bike, ergo I like it. Enough said, thanks upfront.:yo:

1. Pair valve Block
2. 02 sensor re-wire and or Bypassing 02 sensors altogether
3. Accelerator pump upgrade?
4. Temp sensor?
5. PCIII and full tune
6. Starter Valve synchronization
7. Cat Converter Cleanout

also if any of you have had any luck getting Honda to cover SValve synch please note, I know UK riders had some success in this aspect.
:boom:

 

I wasn't trying to be a :violin: drama queen jerkoff,,before my esteemed colleagues, just pissed at Honda for making buyers sift through this problem alone. Much like an 06' FZ1 from what I understand!!

got several good responses on the other site that ammounted to:

get the starter valves synched...run the piss out of it for several thousand miles and it should be cool. If not PCIII and tune. If you want to check it out bikers oracle, tech questions, thread starting OK UK Viffers...

glad I didn't go buy ball bearings specialound:

 

For my 06 I went with a PCIII and O2 sensor mod, running the stock map. The results were exactly what I had hoped for, throttle jerkiness gone, surging gone and a seamless VTEC transition. I'll probably try out the free PCIII accelerator pump upgrade here soon, but I am a little hesitant to mess with it anymore since now it is perfect.

 

Wow. I just priced the PCIII and it runs about $340. Before I spend that kind of money, is it a sure fix? If so, then I have no problem spending the money, but I'd like the reassurance that others have had the same success as Placerville KG.

 

There is a thread for a deal on this site for 245$ no shipping until APR 1st,,,but...your other point is exactly where I'm at, thanks. If there is another way besides 5-10% of the cost of the bike just to get it right, I'll be patient I can still ride the pants off it...:biggrin:

Talked to Honda USA today and my local dealer. Interesting phone call with Honda in that I reported my bike "problem" of not holding throttle at 5k etc.. and politely asked if they had seen my sort of problem before, totally innocent just wondering. The guy Alex was nice, and savvy and replied carefully that he nor Honda could verify nor deny the existence of a problem such as mine with the VFR as it was proprietary information. I agreed and asked the policy on such things and it was exactly as I remembered from Yamaha. Bring bike in, tech drive bike, if problem shop liasons w/Honda rep in area to fix or you are on your own. I did mention the other site and UK Honda that has paid for such SValve synch's. Long and short I'm following their policy and see what happens.

 

What is involved with getting the starter valves synced? Is it safe to assume that on a new bike that they would be in sync? Even so, what would cause them to get out of sync and would that be an ongoing maintenance item?

For $245, the PCIII solution looks even better. Now if we can just get some more feedback on how effective it truly is .....

 

Try a search on "power commanders", there were a few threads a little while back where others posted their experiences with it as well.

 

Other riders have posted good things about blocking the pair valve, and disabling the O2 sensors. I would start with those mods first as they are free or cheap.

Anything that you find out should go in the wiki.

http://wiki.vfrworld.com/index.php/Generation_6

 

I did the starter valve sinc. within my first month of ownership. It helped but did not eliminate the surge/dead spots. I did the flapper disabling and evap removal last week-not much difference. I did the pair removal yesterday and test rode for a very short time(10 miles). From that small ride I could tell a big diff. in throttle smoothness. Took me about 20 min. to do and I think its worth it.

[p.s. bike is 06 with 4500 miles]

 

I see lots of chatter about blocking/removing the PAIR system for a performance gain. The truth of the matter is: there ain't no performance gain aside from the slight weight loss if the system is removed.

The sole job of the PAIR system is to inject filtered air into the post combustion gasses as the gasses make their way out of the exhaust port into the exhaust system. This air injection causes the expelled charge to burn more completely and contributes to lowering emissions.

It is not new. Kawasaki has been using a similar system since the 1970s (I don't remember what their acronym is). Back then we just carved out block off plates from 1/8" aluminum plate and chucked the air valve and it's plumbing into the dumpster. It wasn't done for a performance gain, but it did make the bikes easier to work on.


Rex

 

Thanks MRX and Jev...I didn't know wiki existed thanks.

 

I didn't know it existed either. What a great resource. I'm going to start there before investing any money in a PC.

 

The wiki was only created a week ago and has very little info so far. feel free to add more.

 

Alot of us have had surging issues. Mine were most noticeable with my stock pipes on. When I had my gutted set on, it tended to be a little smoother, but it may not have been. I can tell you without any doubt that the pair mod was not my perception, I know what I'm talking about, it helped tremendously. The idle was smoother, the surges were gone, and the vtec transition was super smooth. I'm sure that alot of vtecs are fine from the factory, but like mine, there's alot that are not.

 

That is their role however after suffering from a slow loss of power and worsening poor fuel economy but oddly not jerkyness, found my front left pair reed valve had carbonized open. This apparently allows burnt gases up into the air box causing me to compensate the power loss with more throttle using more petrol.

Once removed was able to see a gap with the naked eye and once pulled apart, cleaned with brake cleaner re-assembled and installed instant power increase and a returned great fuel economy. :biggrin:

Haven't done the pair mod as written here as would rather work out best way block it off at the reeds themselves rather than the pipe, apparently a Pair / Reed valve eliminator kit available for Superhawk and Superblackbirds and as mine is a pre Cat Gen 5 think no problem if removed, not sure about post Cat Gen 5's or Gen 6's and recollect some talk on the UK VFR site of possible Cat clogging over time although guess the Cat removal mod would fix that problem.

 

That's interesting John. How many miles/KM were on the bike when you found the problem?? This could be something that people are missing when they strip the PAIR system off of their bike.

After the first few Kawasakis we did, customers complained about oil seepage/leaking at the front of the cam cover gasket. Exhaust gas heat was making the gasket brittle and causing it to lose it's seal. The cure was to plug the airways in the cylinder head. Small Welch plugs from a carburetor rebuilder driven into the airway effectively sealed the gasses from the gasket.

I believe that some of the surging or jerkiness people mention could be related to excessive throttle cable slack. On my first ride I had trouble holding steady state throttle, but I noticed that there was about 6-7mm of play at the grip. After adjusting the play to approximately 1.5mm at the grip, steady cruise is no problem in any gear at any rpm.


Rex

 

When bought my '99 Gen 5 in 2005 it only had 2000 miles on it, while smooth enough the Fuel economy was always worse than everone else's VFR even after (2) full service's which included new oil/filter, air filter, plugs and SV balancing.

Most advised to give it a flogging to run it in due to the low milage but the economy still continued to get incrementally worse over the next 8K miles anyway stumbled on this UK VFR Technical link which recommended cleaning the PAIR Valves as they are recognised reasonably common problem over there...Certainly worked for me consumption jumped from 33MPG on cruise to 42MPG immediately after the clean.

One difference to note - the Gen 5's PAIR valves can be dissasembled for cleaning but the Gen 6 is listed as a replaceable unit although the operation to pull out and clean would otherwise be the same.

Pair valve clean "How To" Link by the excellent "Odie" from the UK VFR site:
http://tinyurl.com/2gx4rv