Home Forums 250 Superkarts removing rear wing ??

This topic contains 12 replies, has 7 voices, and was last updated by  Bobby Butler 1 year, 2 months ago.

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  • #10380

    Jeff Metter
    Participant

    So.. I have a PVP with a GasGas 250 that i am thinking of running at Daytona at the end of year.. What i was thinking of doing is to remove the rear wing assembly altogether and run on the high banks just like that… my question is.. can i do that or will there be some sort of overpowering downforce from the front nose area and therefore breaking loose the rear end due to lack of rear end downforce ?? perhaps the high degree of banking may help but i have no idea at all…

    Thanks !!

    #10382

    Brian Wilhelm
    Participant

    <div class=”d4p-bbp-quote-title”>jeffrey wrote:</div>
    So.. I have a PVP with a GasGas 250 that i am thinking of running at Daytona at the end of year.. What i was thinking of doing is to remove the rear wing assembly altogether and run on the high banks just like that… my question is.. can i do that or will there be some sort of overpowering downforce from the front nose area and therefore breaking loose the rear end due to lack of rear end downforce ?? perhaps the high degree of banking may help but i have no idea at all… 

    Thanks !!

    <hr />

    <div class=”bbp-reply-signature”>125 TM Zanardi
    250 GasGas Anderson
    250 GasGas PVP</div>

    Jeff, love to see how the GasGas would do there! IMO, I’d guess if you dialed out some front downforce, it may be fine. Bobby took the wing off his 250 year before last to gain top end, but didn’t like how it drove. I’ve been bugging Don E. to bring his GasGas to Daytona and last time I talked to him, that was still the plan. The magic number is 145!

    #10403

    Sam
    Participant

    There is no reason why you couldn’t do it. Many of the 125cc drivers run without a rear wing in the UK and some people have tried it in 250 Nat at Thruxton.

     

    If you plan on attempting it first thing to want to do is decrease the angle of the nose or probably in your case with the PVP style is make father leading edge even higher the nose.

    Secondly you’d want to decrease the caster angle. decreasing the angle will make steering easier and less prone to snapping away so you can put use more steering. Lastyou if you can move some weight balance to the rear of the kart too.

    Hope this helps somewhat.

     

    #10420

    Jeremy Baldi
    Participant

    Yeah the balance of the kart without the wing will defiantly change.  I have the black laydown F-125 with the big wing.  I have run with and than taken it off for sessions and the balance changes quite a bit.  It has always been drivable but defiantly a little tail happy.  Do you have a diffuser on the kart?  That helps quite a bit to minimize the balance shift and like Sam mentioned shifting some weight to the back will help too.  But for sure taking a little downforce of the front will be the biggest help to balance it though.

    If you do it defiantly post results. Daytona is the one track I think removing the rear wing might be a help.  Everywhere else I have always gone faster with the wing.  Even at MIS this past weekend I ran without the wing and while I went 4 mph faster on the straight but 2.5 secs slower per lap.  Now they only use 1/3 of the oval there instead of 3/4 of the oval like Daytona. I would bring all the parts to put it back on and do a comparison if you can.

    Brian,

    Is 145 the fastest mph you have gone there? Or the fastest a superkart has gone? I thought lay down 250s have hot 160mph so just curious what the number is.

     

    Jeremy

     

    #10445

    Brian Wilhelm
    Participant

    I have not seen a superkart faster than 143. A strong 250 single on a laydown will go 145. Lots of “stories” about Hines going 160+, but the real deal is he went in the low 140’s, according to Marc Crozlyn. Russell jr went 156 in the BRC 250 twin on a laydown and most knowlegeable folk said then that was about the fastest anyone has went.

    Two sharp superkarts drafting can get 144.

    #10453

    Brian Wilhelm
    Participant

    Jeremy, 145.1 is my best top speed there, no draft, no wind.

    My data on the superkart top speeds is based on my observations from racing with them. Generally, my fast lap pretty is much the same as a 250 twin superkart fast lap. They kill me on the infield, but I have them on topend. A well-tuned (Robby Harper) dual engine kart with two 125’s pretty much runs the same laptime, also with 145 top speed.

    Johnny West has very good data on superkart speeds, laptimes, etc. from Daytona.

    #10487

    Jeremy Baldi
    Participant

    Man 145.1 is flying in a F-125.  Even without the wing the best I have ever seen is about 133-135 but I have never been to Daytona were you really have the track to build up there.

    I always wondered about the stories about 160mph but I remember Russell Jr a few years ago going 156 which I know is moving pretty good.  Johnny West was hitting 143 at MIS a few weekends ago and the straight is not near the length of Daytona so the 143-144 must really be were they hit that aero wall.  So it would be interesting for sure to see what Jeff’s kart does without it.

    #10560

    Jeff Metter
    Participant

    Thanks for the insight and information  everyone…i will definately give it a test run or two and i will keep you informed as to the results…btw, last time i was at Daytona with a 250 i think my top end was at about 139 ( between turn 3 and 4 ) and almost every lap just about turn 3 there would come Brian blowing on by in his Purple mean machine…..

    #10628

    Chris Hegar
    Participant

    If your going to remove the wing as Sam noted you may want to add or move physical ballast to the back of the kart to simulate what the down force does for balance at slower and medium speeds. Wing is down force which is basically pressure weight as well as it’s own scale weight, eliminate drag with no wing but maintain grip and balance with ballast.  Scale the kart with wing, remove the wing and led it back to balance. All this is based on having a driver that already needs led to make weight, if your taking it off to make weight your hosed anyway. Ya can’t just remove the wing without adjusting something or it’s gonna rotate off the front like a mother.

     

    Brian, your sprag body is shipping today. Sorry for the delay we have been upside down here due to the IKF nationals.

    #10646

    Brian Wilhelm
    Participant

    Thanks Chris.

    Chris does have a point. I added a splitter to the bottom of a nose I was trying at VIR because it “didn’t look like” it would have enough downforce. Well, after one practice session (and a sixth-gear spin in the esses) in the spin-o-matic laydown I had just created, the splitter came off. I think Jeff’s example will be less dramatic. My splitter was a LONG way ahead of the front wheels, giving it huge leverage.

    I was hoping Bobby Butler or Johnny would jump in since they have both tried Daytona without a wing.

    Jeff, it’s the purple that gives me good topend speed. Everybody knows a yellow kart is good for bottom end, red ones have strong midrange, and purple is for max mph.

    #10652

    Chris Hegar
    Participant

    And black karts will win every time!  ;-)

    #10737

    Johnny West
    Participant

    I can’t get on mylaps any more since they changed thier site. At Daytona; I ran a 156.3 and Randy Johnson running my back up kart ran a 156.6. I believe the top speed was 153. Note this was on the gauge. Back then it was not “GPS” information.
    At MIS I ran 143 mph as shown on the “GPS” on the gauge.Lap time was 118.3
    I never removed the wing to see how the chassis handled.I can not make Daytona this year becuase I will be on a cruise. I do think the DEA will be faster at Daytona. Time will tell.

    #10795

    Bobby Butler
    Participant

    My experience removing the entire rear wing was a 500 rpm increase on the back straight at Daytona.   The lateral stability was diminished as  well as downforce.  Being accustomed to  the handling of a formula 1 superkart I reinstalled the wing assembly less one of the 2 wing elements.  I advise if you want that 500 of so increase you be prepared to do some other adjustments or just let the laydowns do there thing and do what your kart does best and finish.  As far as I know, you will not tech without a wing unless you are in the unlimited class.  

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