Performance improvement

Recently got the cat cleaned out on my 04, also installed Power Commander and loaded map that is ordinarily used with STaintunes with restrictors in place. Also put in accelerator pump upgrade. Figured this would be a fairly close match to stock exhaust with cat cleanout.
Am very pleased with the improved performance and driveability the VFR now has. Is stronger from bottom to top and wheelies much easier now. The sound is much improved especially when under hard acceleration. Will probably try for better optimization with different maps and buttons on PC. BE good BBuck

 

Pull the snuffer plugs out and add a K-N air fitter, you'll like what happens, not to mention oh the sound..

 

Snuffer plugs? Is that the o2 sensors? Got bypasses on them. Thanks for tip on K&N filter. Had one on my Meanstreak and it made a huge difference, but it consisted of a whole different air intake system. Take care BBuck

 

hey buck, just joined and have an 04 vfr like you. love the bike but i need more power. ditched the stock exhaust for 2bros slip ons. how much more power did you get from punching the cat, k&n, and power commander? those were my next mods.

 

has anyone done the pair and flapper valve?

 

Hi Scott , so far I have cleaned out the cat , added power commander with map for two bros exhaust and acellerator pump upgrade, o2 sensor bypasses,and have done the simple drill out on the stock exhaust. By seat of the pants feel these mods made a fairly signifigant power increase. What gave me another, what seemed like about 10 more horse, was going to a 45 tooth rear sprocket. Right now I am quite pleased with the way she runs. If I ever feel like I can ride this bike to its full potential I will add a litre bike to my fleet.

 

Hey Buck--sounds like its working good. Did you synch the starter valves? By cleaning out the cat you mean fully removing the converter correct? Just so I'm clear...
thanks dude.

 

The cat converter housing is still there but with all the insides completely cleaned out. Also have not synched the starter valves.

 

How to do the Flapper Valve mod?

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any one please tell me how to perform the flapper mod?. I've done the pair mod, and my bike an 2002 VFR, runs a lot better!

 

How do you clean out the insides?

 

You go in there and , from what i've read- you gut the F#%^er out completely .

I reckon just by doing that , will give us a bit more to throw at the supers ..
Anyone here got pics of the internals being given the hook and claw treatment ? anyone ?

 

Some pics and "how to" would be great! I read in another thread that you you use a crow bar and a 4 pound hammer as the outlet is at an angle not allowing it to be drilled out! Shees, that sounds a bit harsh! My VFR and a crow bar aint a good match!

 

has anyone done a dyno run since gutting the cat? would like to see what a decent map and performance gains would be. a few have picked up headers from the 98 VFR, where i just installed a set of Motad pipes.

 

When gutting the cat, the easiest way is to take and drill two pilot holes in the rear of the cat on the bottom half. then drill those out to about 3/4 inches. then use a long drill or handle-less screwdriver in a drill motor and work the stuff out. it takes a few hours. Once gutted, take the thing down to the local muffler shop and they will plug weld the holes you made for about 20 bucks. I'll see about getting some pics on here soon. IMPORTANT! when you remove the center stand... then center stand bolt on the right side of the bike has reversed threads!!!!

 

Thanks a mil! I did manage though by cutting the bottom half of the cat open, completely gutting the insides and welding it back together again without removing the stand and even having the entire process done on the bike!

 

Ditto on that one , except that MY Crazed Welder decided to strip the Bikes Fenders , and this is the part where i almost went to tears ...

But I gritted my teeth , and He got done !! Thank heavens though ...........

 

Can Someone Please re-iterate an earlier poster's request on the Flapper valve Mod gents ? Im thinking , after playing with it , that this was yet another simple emission test thingie thingie Honda decided to install on the intake .......

 

if you are refering to the "flapper valve" actuated by a diaphram on the air box, its controlled by the E.C.U. and opens and closes according to engine load and RPM. The only reason i know this is because of the shop manual!! I disconnected the 12 volts to the seleniod that cotrols the vaccum to the diaphram, this seems to result in a smoother throttle also.

 

I know Of some posters mentioning that they plastic weld the thing .
Now what Im trying to Find out is : do they weld it in the OPEN position , or CLOSED ???

This bike seems to have so many technical gadgetries it's no wonder it's under-powered . If the bike was built a little more simplistic , I think better power gains would be realized . I also notice a slight jerkiness when holding the throttle at 3500 rpm at slower speeds , but I doubt whether unpluggin all this will help with that ?
I mean- Just how Smooth ARe you guys getting it to work now ??
I did the Pair valve mod , plus the Cat . Those two seemed a bit more obvious than this flapper valve Mod .

 

Why Why Why?

Hi

My name is Gerhard and I recently bought a 2007 VFR (red) from Honda Midrand.

I cannot understand the changes to a near perfect bike. The standard one does something like 12.17 s on the drag with aspeed of 191 km/h! I think it is good?

Where do you stay, perhaps we can meet?

I am from Sinoville in Pretoria

Later:amen: