It turns out some of the items I assumed were in poor shape weren't (like the chain), and with some varsol and a brush, the rear wheel and swingarm have come clean. The rear shock looks like it has never been removed, so I think I might send it off to RMR suspension to get rebuilt. The forks seem OK, and there has apparently been a relatively recent installation of fork seals. Look fine, regardless. I also set about removing some of the extranneous parts as per the RC51 forums -- the PAIR system and the Flapper Valve system.
This is what the PAIR system is all about:
The exhaust emission control system consists of a secondary air supply system which introduces filtered air into the exhaust gases in the exhaust port. Fresh air is drawn into the exhaust port whenever there is a negative pressure pulse in the exhaust system. This charge of fresh air promotes burning of the unburned exhaust gases and changes a considerable amount of hydrocarbons and carbon monoxide into relatively harmless carbon dioxide and water vapor. The PAIR system is controlled by the ECM using check valves and a solenoid.
Removal of the PAIR system will yield three main benefits: 1) weight reduction 2) reduction of engine compartment clutter 3) increase in the scavenging ability of the exhaust system.
And here's everything you need to know about the flapper valve:
Many of you have complained about the dip in power between 5000 & 7000 rpm & others like myself have had an annoying fueling glitch (hiccup) at 6800 rpms especially with the Moriwaki's & a good map installed, although all the bikes are affected by the flapper valve, certain exhaust & map combos highlight this problem. Bill Staab has found a solution! (and wrote most of what you are about to read...)
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.
The process to remove these items is pretty involved, and also requires some aftermarket pieces to plug holes, hoses, and parts on the engine. Today I set about taking the stuff off, and when the parts come in, putting them in place and tidying things up.
The flapper valve is a little soleniod-controlled gate in the intake snorkel. Taking it all off was pretty much a cinch. The unit that controls the valve, once removed, leaves a gaping hole in the intake just behind the guages. A nice machined piece that screws into place is on the way via ebay, from a seller that also sells some machined plates that take care of the PAIR covers outlined above.
I'm obviously mechanically inclined if I like the looks of bikes without bodywork, as much as I do when they are "fully clothed". The greenish cover over the clutch is made of magnesium. The cover ahead of it has "HRC" stamped into it -- for Honda Racing Corporation. Both wheels have a nice satin black finish to them -- perfect color for any streetbike, if you ask me! Electical gubbins draped over the subframe will be put back into place when the undertail is installed. The battery box is also in the subframe, and part of that needs to be cut to suit. Decided to take it all apart to make the cutting easier!
These are the throttle bodies. Again, compared to the Ducati, the airbox was a breeze to remove. The velocity stacks inside the airbox mount to the intake plenums of each injector body. For screws, and some hoses, and it comes off pretty nicely. Turns out the bike has some pretty nice BMC air filters already installed -- me with K&Ns on the way! However, I have more experience with the K&N filters, and the fluids necessary to clean and oil them properly -- not sure what is required with the BMC stuff -- might be the same...
As I said, a few items are on the way -- FMF exhausts, a radial front brake adaptor kit, CBR1000RR radial brakes and master cylinder, some swingarm spools (currently using some bolts), a rear hugger (to keep the shock in better shape!), some lightweight exhaust brackets (don't think I'll be carrying any passengers on this!), and some new tires -- Bridgestone BT-021 sport-touring rubber. As it comes in, I'll show some pics of it going on the bike. Lastly, removing the tank has made all of this work much easier to perform -- as it will be color-matched to the new bodywork, it needed to come off anyway.
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