advice for exup valve and flapper mod on cbr 929 - Honda Motorcycles - FireBlades.org
Honda FireBlade Discussion of the Honda CBR 900RR, Honda CBR 929RR, Honda CBR 954RR, and Honda CBR 1000RR Motorcycles.

User Tag List

Reply
 
LinkBack Thread Tools
post #1 of 25 Old 06-20-2016, 7:37 AM Thread Starter
 
Join Date: 01-15-2015
Location: UK
Posts: 58
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 7 Post(s)
Reputation Power: 5
 
advice for exup valve and flapper mod on cbr 929

Hello all,

I am about to have some work done on my 929.

I am having a new end can fitted to the original exhaust, i.e. to the original headers and mid section/valve section.

I am then having a pc v fitted, then the bike dynoed and tuned up for the
new exhaust. I will post the before and after dynos for anyone who is interested once I get them.

A k and n air filter is being fitted.

The exup valve will be wire locked on open in the original exhaust, effectively removing it.

The original servo etc. and wiring will be left in situ in order to avoid mil codes etc.

My question is - should the flapper mod in the airbox always be done in conjunction with wiring the exup valve open?

There seems to be no conclusive evidence that the flapper mod makes genuine performance improvement, or if there is evidence I have missed it.

Any thoughts or advice on the above would be very welcome before I take the bike in for it to be done, particularly by anyone who has done something similar, I note backdoc you have done something like this looking at your signature on your 954?
TheGSL is offline  
Sponsored Links
Advertisement
 
post #2 of 25 Old 06-20-2016, 1:49 PM
 
Join Date: 11-14-2009
Location: Morristown, Tennessee
Age: 44
Posts: 823
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Reputation Power: 56
                     
Garage
Re: advice for exup valve and flapper mod on cbr 929

Keep the stock filter over the k-n filter. The flapper in the airbox is only there to decrease intake noise. Remove all of it including cable to servo. With the stock header a functioning exhaust valve will provide the best performance. Fitting an aftermarket muffler and custom tune will not gain much if any power. My bike made same peak hp before my custom dyno tune. The custom tune gained torque in the lower rpms and smoothed out the overall dyno graph.

SOLD: 03 CBR954
backdoc is offline  
post #3 of 25 Old 06-20-2016, 1:53 PM
 
Join Date: 11-14-2009
Location: Morristown, Tennessee
Age: 44
Posts: 823
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Reputation Power: 56
                     
Garage
Re: advice for exup valve and flapper mod on cbr 929

Here is a deal on a 954 header and midpipe if the seller will ship it to you. Just have to find a muffler to fit.

03 Honda CBR 954 Leo Vince Header | eBay

SOLD: 03 CBR954
backdoc is offline  
Sponsored Links
Advertisement
 
post #4 of 25 Old 06-20-2016, 2:11 PM
 
Join Date: 03-12-2016
Location: usa
Posts: 474
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Reputation Power: 0
     
Re: advice for exup valve and flapper mod on cbr 929

"My question is - should the flapper mod in the airbox always be done in conjunction with wiring the exup valve open?"
Yes.

"There seems to be no conclusive evidence that the flapper mod makes genuine performance improvement, or if there is evidence I have missed it."
Think of what you are doing. No cam change, no porting, no lightening of the valvetrain, no turbo, just creating a faster event to occur via time. Think about it. Air thru a crack in the door is a breeze or drag. An open door or a door off the hinges, that's all the air thru that door's new gap, right? Didn't the air enter faster, sooner, quicker? That's it.

Apply it to one cylinder clogged with air doors, and one cylinder without a door. If you start the engines over at the same time, who speeds along into the camber sooner? I rest my case.
Catch22 is offline  
post #5 of 25 Old 06-20-2016, 3:30 PM
 
Join Date: 11-14-2009
Location: Morristown, Tennessee
Age: 44
Posts: 823
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Reputation Power: 56
                     
Garage
Re: advice for exup valve and flapper mod on cbr 929

Here is how the system works
Attached Thumbnails
hvix3.jpg‎  

SOLD: 03 CBR954
backdoc is offline  
post #6 of 25 Old 06-20-2016, 3:42 PM
 
Join Date: 03-12-2016
Location: usa
Posts: 474
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Reputation Power: 0
     
Re: advice for exup valve and flapper mod on cbr 929

Quote:
Originally Posted by backdoc View Post
The custom tune gained torque in the lower rpms and smoothed out the overall dyno graph.
Catch22 is offline  
post #7 of 25 Old 06-20-2016, 3:52 PM Thread Starter
 
Join Date: 01-15-2015
Location: UK
Posts: 58
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 7 Post(s)
Reputation Power: 5
 
Re: advice for exup valve and flapper mod on cbr 929

backdoc and catch22, thanks a lot for the replies, much appreciated.

Okay, I am now in agreement with you to get the flapper mod done too, and seeing the filter is being replaced, it should be easy enough.

I have read previously about not using k an n, about engines running lean etc., however, I note too that you backdoc use a bmc filter, and not stock. The people I am using for the work are professional tuners, and their tuner is a professional road racer and short circuit, competes in the TT etc., so I am satisfied they know their business. My blade is purely for road use, I would never take it on a track day. Is the k and n really such a bad idea? A new stock filter I think won't be much cheaper, the tuners are the ones who said replace the filter with a k and n.

Thanks for the link to the Leo Vince, but I am not sure they would ship it, and I would be hit by uk customs charging me import
tax on it too. It's a pipewerx end can I am having fitted, they are decent enough exhausts.

I am happy to leave the cabling and servo etc. in, should I wish to change things or go back to stock later, unless they
really will cause trouble being left in situ?

I am hoping for better fuelling and a small power increase after the custom map after dynoing.
TheGSL is offline  
post #8 of 25 Old 06-20-2016, 7:16 PM
 
Join Date: 03-12-2016
Location: usa
Posts: 474
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Reputation Power: 0
     
Re: advice for exup valve and flapper mod on cbr 929

"Is the k and n really such a bad idea?"

Yes, bad idea. Larger microns enter, score the cylinder walls is one. Add the groves to the cylinder wall, the face of the rings and those score marks, there goes compression you stack them all up as one. Worse for street use.
Catch22 is offline  
post #9 of 25 Old 06-21-2016, 2:26 AM
 
Join Date: 04-20-2016
Location: Today is all I need
Posts: 433
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Reputation Power: 0
 
Re: advice for exup valve and flapper mod on cbr 929

Senile catch with a net, you could perk up your CB750 with some K&N pods.
I've used K&N for decades and have incredible mileage out of everything I've used it on, not once did I suffer a need for an overhaul.
I guess that's why the company has been around for 40 years and sells millions of filters successfully without any class action lawsuit for wasted engines.
Countless testimonials praise the product and the only gripe is whether you get the hp increase or not, or BMC offers better, which has a very similar filtering media.

My personal favorite filter is a BMC. BKING loved it.
Just because we use the internet, doesn't mean wives tales don't interfere with the facts.

Last edited by 1926; 06-21-2016 at 12:39 PM.
1926 is offline  
post #10 of 25 Old 06-21-2016, 3:30 PM Thread Starter
 
Join Date: 01-15-2015
Location: UK
Posts: 58
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 7 Post(s)
Reputation Power: 5
 
Re: advice for exup valve and flapper mod on cbr 929

Quote:
Originally Posted by 1926 View Post
Senile catch with a net, you could perk up your CB750 with some K&N pods.
I've used K&N for decades and have incredible mileage out of everything I've used it on, not once did I suffer a need for an overhaul.
I guess that's why the company has been around for 40 years and sells millions of filters successfully without any class action lawsuit for wasted engines.
Countless testimonials praise the product and the only gripe is whether you get the hp increase or not, or BMC offers better, which has a very similar filtering media.

My personal favorite filter is a BMC. BKING loved it.
Just because we use the internet, doesn't mean wives tales don't interfere with the facts.
Thanks for the reply. As I say, the tuners have suggested it, not me, I do appreciate everyone's feedback here, just trying to best inform myself.
TheGSL is offline  
post #11 of 25 Old 06-21-2016, 8:20 PM
 
Join Date: 03-12-2016
Location: usa
Posts: 474
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Reputation Power: 0
     
Re: advice for exup valve and flapper mod on cbr 929

Quote:
Originally Posted by TheGSL View Post
As I say, the tuners have suggested it, not me... just trying to best inform myself.
Here is how informed I am. The current posts going on the last few days have been around air cleaners and HP loss. The same kind of mods to another bike I'm more familiar with, this too lost HP on the dyno tests. So the aftmrkt filters seem to show a possible linear loss in HP. It's not like HP happens all at once. So starting out is a loss you figure.

The second part about this mod is engine preservation. If I am racing, want more HP, the factory race kit instructions walk you thru the 'removal and discarding of the air cleaner element.' But see, that's all out racing, when there is now an 'hour life maintenance' range you meet or run the part too long and it fatigues, cracks off, blows the engine, etc.

But for JoeA on the street to look for HP in all the wrong places I've been informed real quick as to certain suggestions on the net. Since oil and air are the secrets to longevity in keeping the bike's engine in top health... Micron for micron, figure out what you are doing to the engine. So between tuners needing to go on line and see a power loss to internet suggestions eating the engine out... I'm now well informed how JoeA prepares his engine for performance or peeformance is pissing out the power.


Signed,
And you wonder why someone has all that info and goes ahead anyway.
Catch22 is offline  
post #12 of 25 Old 06-21-2016, 9:07 PM
 
Join Date: 04-20-2016
Location: Today is all I need
Posts: 433
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Reputation Power: 0
 
Re: advice for exup valve and flapper mod on cbr 929

Quote:
Originally Posted by TheGSL View Post
Thanks for the reply. As I say, the tuners have suggested it, not me, I do appreciate everyone's feedback here, just trying to best inform myself.
Glad you didn't succumb to one frail and feeble forum folly, when all you got to do is watch a video, for Joe A. Remember, a concise answer is a sign of intelligence.

1926 is offline  
post #13 of 25 Old 06-22-2016, 10:01 AM
 
Join Date: 03-12-2016
Location: usa
Posts: 474
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Reputation Power: 0
     
Re: advice for exup valve and flapper mod on cbr 929

"Remember, a concise answer is a sign of intelligence."

When dodging vehicles coming into your lane, you want the compression at its premium later on down the road... "Pre-clean your air filter."

Catch22 is offline  
post #14 of 25 Old 06-22-2016, 10:12 AM
 
Join Date: 04-20-2016
Location: Today is all I need
Posts: 433
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Reputation Power: 0
 
Re: advice for exup valve and flapper mod on cbr 929

Quote:
Originally Posted by Catch22 View Post
Here is how informed I am. The current posts going on the last few days have been around air cleaners and HP loss. The same kind of mods to another bike I'm more familiar with, this too lost HP on the dyno tests. So the aftmrkt filters seem to show a possible linear loss in HP. It's not like HP happens all at once. So starting out is a loss you figure.

The second part about this mod is engine preservation. If I am racing, want more HP, the factory race kit instructions walk you thru the 'removal and discarding of the air cleaner element.' But see, that's all out racing, when there is now an 'hour life maintenance' range you meet or run the part too long and it fatigues, cracks off, blows the engine, etc.

But for JoeA on the street to look for HP in all the wrong places I've been informed real quick as to certain suggestions on the net. Since oil and air are the secrets to longevity in keeping the bike's engine in top health... Micron for micron, figure out what you are doing to the engine. So between tuners needing to go on line and see a power loss to internet suggestions eating the engine out... I'm now well informed how JoeA prepares his engine for performance or peeformance is pissing out the power.


Signed,
And you wonder why someone has all that info and goes ahead anyway.
Quote:
Originally Posted by Catch22 View Post
"Remember, a concise answer is a sign of intelligence."
Yep, and you often blather forever on your posts, one quoted above for your reference. Now you got the whole forum wondering what the hell you're trying to say to people with your convoluted methods of speech. Told you.

Last edited by 1926; 06-22-2016 at 3:17 PM.
1926 is offline  
post #15 of 25 Old 06-22-2016, 11:17 AM
 
Join Date: 03-12-2016
Location: usa
Posts: 474
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Reputation Power: 0
     
Re: advice for exup valve and flapper mod on cbr 929

I'll let my air cleaner speak for me. I'll let the shop manual show you how locked out of the loops of the systems; you mess with flappers of air or exhaust. You keep perpetuating the loss of HP with the air cleaner, and you still keep detuning the bike and shake up less HP, as it moves around rather than makes more HP.

That's the communication gap as I flap my jaws enjoying how one detunes the generic computer bike on the net.
Catch22 is offline  
Reply

  Lower Navigation
Go Back   Honda Motorcycles - FireBlades.org > Honda Motorcycle Models > Honda FireBlade

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Honda Motorcycles - FireBlades.org forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
A valid e-mail address is REQUIRED. You will not have access to any site features until you activate your account using the activation e-mail that is sent to this address.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
CBR929 exup valve Allyboy Honda FireBlade 15 07-31-2015 7:48 AM
exup valve ako954 Honda FireBlade 2 12-24-2011 11:47 AM
CBR929 exup valve aashort63 Honda FireBlade 2 10-24-2011 2:28 AM
exup valve volatileatom Honda FireBlade 13 06-03-2007 9:31 PM
pair valve & flapper valve plates? texasixes Honda RC51 4 07-05-2006 2:53 AM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 
For the best viewing experience please update your browser to Google Chrome