RC 51 info "free mods"

dReWpY · 02-24-2008, 02:01 PM

This is for all rvt lovers out there, enjoy

starting off the "free mods"
first off: do the flapper mod, it will make a world of difference

By disconnecting the vacuum line to the flapper valve in the air intake duct you can completely eliminate the hiccup at 6800 rpm & reduce the power dip we have all seen on the dyno runs between 5000 & 7000 rpm.

As the flapper valve is an air intake noise control device which is not used on the basic racer, but rather only on the street legal bikes where noise levels are monitored by the EPA. It is advised that you only do this mod to "race only" bikes.

Having gotten the legal disclaimer out of the way let's get back to the flapper valves function. The valve is partially responsible for the power dip between 5000/7000 RPM. The flap is normally open. If you disconnect the vacuum line it will always stay open. You can remove the flap if you like. although it shouldn't make much difference with the stock air box. The HRC and Moriwaki air boxes have a larger duct with no flap for the race motors. The flap closes at about 5500 rpm which reduces the intake duct about 65%. It opens back up about 6700 rpm. This is done to reduce intake noise on the road bikes. The mod is done by simply disconnecting the hose at the diaphragm switch & plugging the hose with a screw,bolt or whatever you find handy or aesthetically pleasing.

next "soft rev mod"

http://rc51.org/b2a15.htm

and the PAIR removal
http://rc51.org/pair.htm

Mr Lefty · 02-26-2008, 07:48 PM

which one makes your MPG go to shit!?

dReWpY · 02-26-2008, 07:50 PM

the one where you ride it like supposed to.... if i babied it the mpg wouldnt be nearly what it is, but the smile-per-mile would drop, and thats just not acceptable

the pc3 will actually drop it more.. but the hp will go up, along with the smoothness

Mr Lefty · 02-26-2008, 07:56 PM

Quote:

Originally Posted by drewpy

the one where you ride it like supposed to.... if i babied it the mpg wouldnt be nearly what it is, but the smile-per-mile would drop, and thats just not acceptable

the pc3 will actually drop it more.. but the hp will go up, along with the smoothness

Really... that's all that matters

dReWpY · 02-26-2008, 09:45 PM

Quote:

Originally Posted by Ebbs15

Really... that's all that matters

what no cheers smilie?!

im working on it, im seeing ppl using smilies that i havent gotten too yet

Mr Lefty · 02-26-2008, 09:50 PM

Quote:

Originally Posted by drewpy

im working on it, im seeing ppl using smilies that i havent gotten too yet

it's cool... just suprised.... not a huge thing

Cutty72 · 02-29-2008, 03:31 PM

Quote:

Originally Posted by Ebbs15

which one makes your MPG go to shit!?

me thinks it's the big bore honda V-twin mod...

marko138 · 02-29-2008, 05:04 PM

Quote:

Originally Posted by Cutty72

me thinks it's the big bore honda V-twin mod...

I'm hearing the MPG's on the big Buell aren't so great either.

OneSickPsycho · 02-29-2008, 08:54 PM

What can you say... High performance, liquid cooled v-twins are some thirsty mutha's!

Cutty72 · 03-01-2008, 04:45 AM

Quote:

Originally Posted by marko138

I'm hearing the MPG's on the big Buell aren't so great either.

from what i've heard... mid to high 30's...

we shall see...

If i can average about 38, i'll be happy...

gettin 43ish on the SV... and a lot more smiles i'm sure on the 1125... so, it equals out

anything is better than my pickup at 15... even drewps RC!!!

02-24-2008, 02:01 PM	#1
dReWpY RIP REX Join Date: Feb 2008 Location: Murfreesboro, TN Moto: 2008 1125R Posts: 7,467	RC 51 info "free mods" This is for all rvt lovers out there, enjoy starting off the "free mods" first off: do the flapper mod, it will make a world of difference By disconnecting the vacuum line to the flapper valve in the air intake duct you can completely eliminate the hiccup at 6800 rpm & reduce the power dip we have all seen on the dyno runs between 5000 & 7000 rpm. As the flapper valve is an air intake noise control device which is not used on the basic racer, but rather only on the street legal bikes where noise levels are monitored by the EPA. It is advised that you only do this mod to "race only" bikes. Having gotten the legal disclaimer out of the way let's get back to the flapper valves function. The valve is partially responsible for the power dip between 5000/7000 RPM. The flap is normally open. If you disconnect the vacuum line it will always stay open. You can remove the flap if you like. although it shouldn't make much difference with the stock air box. The HRC and Moriwaki air boxes have a larger duct with no flap for the race motors. The flap closes at about 5500 rpm which reduces the intake duct about 65%. It opens back up about 6700 rpm. This is done to reduce intake noise on the road bikes. The mod is done by simply disconnecting the hose at the diaphragm switch & plugging the hose with a screw,bolt or whatever you find handy or aesthetically pleasing. next "soft rev mod" http://rc51.org/b2a15.htm and the PAIR removal http://rc51.org/pair.htm

02-26-2008, 07:48 PM	#2
Mr Lefty TWFix Legend Join Date: Feb 2008 Location: Denver CO Moto: 01 BMW F650GS Dakar Posts: 15,677	which one makes your MPG go to shit!?

02-29-2008, 08:54 PM	#9
OneSickPsycho Ride Like an Asshole Join Date: Feb 2008 Moto: nothing... Posts: 11,254	What can you say... High performance, liquid cooled v-twins are some thirsty mutha's!