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Legend has it that the caps can melt....
I don't buy it but the shiny metal caps are easier to find when they fall on the floor.. Lol
LRRS/CCS Expert #820 / RSP Racing / Woodcraft / MTAG Pirelli / Dyno Solutions / Tony's Track Days / Sport Bike Track Gear / GMD Computrack /
Metal caps have an o ring in them that can prevent air loss in the case of a valve core failure.
Everyone said all the good stuff.
Mike K. - www.goMTAG.com - For Pirelli tires, Moto-D tire warmers, and Woodcraft parts
LRRS/CCS Expert #86 / RSP Racing / Woodcraft / MTAG Pirelli / Dyno Solutions / Tony's Track Days / Sport Bike Track Gear / 434racer / Brunetto T-Shirts / Knox / Crossfit Wallingford
R.I.P. - Reed - 3-23-2008
I have most def passed inspection and raced with no caps at all. Lol
I will be posting up personal gear soon. Helmet (L) with eject system. Spyder 48/58 Silver Suit. Suit drying hanger and trailer travel heavy duty hanger. The very best Spyder boots. Gloves (L). Chest and back protector. And a carry bag and spare stuff. Rookie gets first shot. 508 713 5663
Make sure you swing by the RSP garage and say hi(Center garages, nearest the pre-grid), and like Adam said, definitely don't miss the BBQ Sat night after the trophy ceremony.
Mike K. - www.goMTAG.com - For Pirelli tires, Moto-D tire warmers, and Woodcraft parts
LRRS/CCS Expert #86 / RSP Racing / Woodcraft / MTAG Pirelli / Dyno Solutions / Tony's Track Days / Sport Bike Track Gear / 434racer / Brunetto T-Shirts / Knox / Crossfit Wallingford
R.I.P. - Reed - 3-23-2008
Last edited by OreoGaborio; 08-24-14 at 06:43 AM.
-Pete LRRS/CCS #81 - ECK Racing, TonysTrackDays
GMD Computrack Boston | Pine Motorparts/PBE Specialists | Phoenix Graphics | Woodcraft | MTag-Pirelli | OnTrack Media
The Garage: '03 Tuono | '06 SV650
Mike is absolutely correct.... but…. it may not be obvious as to one key reason why....
Q. Why would I lose air pressure without a sealing valve cap?
A. Due to centrifugal force opening the poppet valve in valve stems.
I just calculated the how and why.
Turns out the poppet valve opening can happen around 130 MPH due to centrifugal force on a straight valve stem (90o valve stem is a non issue).
(Even at NHMS the fastest racers get to approx. 137-143mph down the straight (I measured with a radar gun some time back).
I took into account numerous factors (including the obvious such as wheel speed/RPM, radius to valve stem etc to factor G forces) such as:
-Weight of valve poppet and valve spring -
-G force acting on poppet valve at various speeds (at 200mph there is 1600G force trying to open the valve)
- Mechanical force (spring) required to open poppet = approx. 400grams
- Internal tire pressure keeping the poppet valve closed of 30psi
- Took into account pressure drop at inner rim surface due to centrifugal force on captured air.
- Diam of poppet surface (0.090") exposed to internal it pressure (turns out the air pressure keeping the poppet valve closed it a lot less than you may think).
So that’s why it’s important, a simple metal sealing valve cap is your last line of defense to losing air pressure.
Last edited by xsiliconkid; 08-25-14 at 09:59 AM. Reason: correction 0.09" not 0.9"
Graham
"If computers get too powerful, we can organize them into a committee — that will do them in"
Today I was servicing the chain and tires on my street bike. I noticed the plastic OE caps on my valve stems have o-rings in them.
http://www.amazon.com/Set-Bullet-Val.../dp/B009C9PA96
Metal
Am I going to get grief from tech for anything here?
Love how the official clarified everything about the topic and people still developing theories
They aren't mutually exclusive.
Last time I took the sport bike to the track, I could not complete a session without it dieing coming out of t12. I couldn't repeat the failure in the pits or running up and down the infield. It seemed to be running out of fuel. I replaced everything between the tank and the carbs, but haven't tried t12 yet.
So far, I am signed up for the basics class.
How that goes will determine much of the rest.
One step at a time.
Get The Fuck Out of here.....
Are you shitting me.. Way to go Jason!!!!!!! You racing the CBR or the Wing?![]()
LRRS/CCS Expert #820 / RSP Racing / Woodcraft / MTAG Pirelli / Dyno Solutions / Tony's Track Days / Sport Bike Track Gear / GMD Computrack /
Signing up for the basics course is easy... Only a valid credit card is required.
There are plenty of aspects of this thread which are still true.
I'm actually still more comfortable on the wing than I am the CBR. I'm still waiting on that race class the requires factory stereos. Plans for Friday don't include the GL.
This post still applies.I'm pumped for next weekend. And my candyass is just doing another track day.
No theories. Just asking questions. I am half irish and a professional inganeer by day. I'm practically designed to be a pain in the ass.
Ultimately rules are rules. You pay to play or gtfo. Ain't even my game anyway.
Bubba I was directing anything to you. I find it super entertaining anyways