1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

rying to explain this crash...Wera Grattan CCW 6-11-2017

Discussion in 'Race Reports' started by guidout, Jun 20, 2017.

  1. guidout

    guidout Active Member

    Hey guys,
    I have been riding on the track since couple of years and never crashed so I knew it was coming...I'm constantly improving and I knew that the day when good tires and good suspensions won't be enough to cover my mistakes anymore.
    Only thing I have been hoping for is that I could learn something from my first crash. I have been thinking a lot about it...especially because I'm spending a lot of time next to my bike lately trying to rebuild it...but I honestly cannot find a clear explanation for this crash.

    The crash happens at the end of the video but if you watch it all you might gain some more on my riding style:


    The causes I can attribute to the front washout out are:
    1 - just a bit too hot or too much lean angle for the speed (I doubt this one)
    2 - front end loaded too much. I fully close the gas before entering the corner, now I think I should have applied a bit of maintenance throttle to help release a bit of front load
    3 - just bad luck...maybe changing track conditions, some debris in the particular spot in that particular moment, anything random... (I doubt this one too)
    4 - some bad input on the handlebar

    Also a good background info:
    - tires: bridgestone V02, pressure 33/24
    - temperature was pretty high, high 80s, not windy but cloudy, so I would say that the track conditions were close to perfect
    - my pace was high 1:23s, the day before I did my personal best 1:23.461

    Any input is very welcome. I still have tons to learn and I really would like to have your opinions.

    Thanks,
    Guido
     
  2. RRP

    RRP Kinda Superbikey

    So you chopped the throttle before initiating the turn and rolled on again?
     
  3. mpusch

    mpusch Well-Known Member

    Too much brakes for that amount of lean angle :D where do I send the bill? :p

    I don't think maintenance throttle is the answer very many times...

    What happened to your helmet?
     
  4. guidout

    guidout Active Member

    Yes, you can hear from the audio too. I chop the throttle a second before entering the corner and do nothing afterwards...until the crash.
    My question is if I should have rolled on just a little bit to put the bike back into a neutral condition.

    Honestly, I don't think I was braking. The engine braking wasn't too much hard, since I should be at around 10krpm in third there.
    My helmet doesn't even have a scratch. Why?
     
  5. RRP

    RRP Kinda Superbikey

    I'm curious if when you got back in the throttle if the rear broke loose and you lost the rear. Seems like from the video the rear steeped out and then you lost the front and went down.

    Just a guess.

    You're right in trying to deconstruct what happened so as to learn from it. Good luck.
     
  6. britx303

    britx303 Boomstick Butcher…..

    You run 33 psi on the vo2 front? Seems kinda high imo. I run 28 off the warmer,and thats what the b-stone guy said to go with.Not that this necassarily caused the crash.....I didnt watch the video yet.Just sayin'
     
  7. TLR67

    TLR67 Well-Known Member

    You keep it on until back in the Pits..... Especially with Bikes still going around...
     
    CTarna, mpusch and SuddenBraking like this.
  8. stangmx13

    stangmx13 Well-Known Member

    it looks like the front tire was underloaded and u tried adding more lean angle to fix a bad line. i bet u wouldnt have crashed if u had increased the contact patch with the brakes.
     
    Bruce likes this.
  9. guidout

    guidout Active Member

    I am not THAT guy...the race was finished and the track empty...I just cut the video. As soon as I crashed I gave a thumb up to the corner worker and went as far away as possible from the track...with all my gear still on.
     
    TLR67 likes this.
  10. guidout

    guidout Active Member

    that's an interesting point. You are the only one (so far) that actually noticed that I was a bit off (a bit wider), but I don't get your unloaded front point. I washed out with the front, what makes you think that braking would have increased the grip of my front?
    Thanks
     
  11. guidout

    guidout Active Member

    33 front is what 3 bridgestone guys told me...and what bridgestone suggests
    http://www.trackdayguiden.dk/rg/pdf/bridgestone.pdf
     
  12. stangmx13

    stangmx13 Well-Known Member

    braking increases the load on the front tire which increase the size of the contact patch which increase front grip. havent u ever wondered how great riders brake later than u at faster speeds while not crashing? its not some magic front suspension and we know the run the same tires. its because they know how & when to use the brakes. of course, there is a point where it doesnt help anymore, where more brake does overload the front tire. but thats not this.

    your front tire likely unloaded slightly while going over that little rise. that reduced the load and therefore reduced the grip, while at the same time u asked for more grip by adding lean angle. it was the perfect storm to give u absolutely no warning that the front was going to let go. someone setting lap records probably brakes into that corner, gets their turning done sooner before the rise, and gases it hard.

    re: front tire pressure... the later and harder you brake, the more front tire pressure u will probably want/need. this prevents the tire profile from flattening out while braking and still allows the front end to turn. for example, Dunlop recommends 33psi to trackday riders. i race on 35-37psi and have heard of some using up to 42psi. and of course, fast racers dont need low pressure to keep the tire hot. they generate it with hard braking.
     
  13. guidout

    guidout Active Member

    honestly, I am not sold on it...but what you say might apply to this case (with the small hill)
    What you say makes physcally sense...traction is function of friction and load. More load equals more traction, no doubt on that. However, as you brake you are loading more the front so you get more traction BUT...mmm...I had a but, but now I'm not convinced about that anymore...lol
    I'll try to brake harder but I don't know if I have the balls to brake there yet
     
  14. dobr24

    dobr24 Well-Known Member

    There is a (was) a small bump on the very inside of this corner a few years ago and I hit it going the other direction which caused a massive high side. Could be it's still there.
     
  15. ScottyRock155

    ScottyRock155 A T-Rex going RAWR!

    Agreed. I had a friend crash there (going the other direction), because there is a decent bump in the track.
     
  16. mike-guy

    mike-guy Well-Known Member

    You just weren't able to catch me thats all I know :) I did know you were coming though. If you've only been riding a few years and this is your first crash I am seriously impressed. It was my first time running that track CCW and only my 3rd time ever but that hill really does unload the suspension when you crest it. Personally I wouldn't over think it (although I used to crash A LOT and didn't consider why most the time) and just adding in a few factors here like running wide, chopping throttle, cresting the hill, it as just enough to wash out the front. IMO. And again good racing, hoping to see you and Alex at Mid Ohio?
     
    guidout and MurfSVR like this.
  17. MurfSVR

    MurfSVR Well-Known Member

    Is that turn off camber?


    Sent from my iPhone using Tapatalk
     
  18. Jaketheone46

    Jaketheone46 Well-Known Member

    I seen a few other moments where I thought the crash was coming. You was definitely running hot when it did. You definitely looked pretty darn hot in quiet a few moments of that video. I would say if there is a bit of a bump there coming from the other direction it’s what caused it. You was definitely going for it.
     
  19. notbostrom

    notbostrom DaveK broke the interwebs

    front got light cresting the what appears to be a rise in the corner? Either on the gas or trail braking could have made the front react more favorably. Don't know the track so I could be waaaaay off
     
  20. younglion

    younglion Well-Known Member

    Looks like you completely unweighted the bike at the top of the Crest in the track removing all the downward pressure on your contact patch.

    Our local track has an uphill section that catches out a LOT of track day guys as they crest it, unweight the rear, initiate turn in, and whoooops... It was so prevalent that everyone would be warned about it in the riders meeting each morning.

    Experienced racers know the correct line to use and how to make sure the weight transfer is completed before making the transition to full lean and asking more from the tire.

    On a different track than mentioned above, but my one and only highside was caused by the same issue on a wet track day. The track rising then levelling off ever so slightly and wasn't even detectable at speed (walking it later that night it was quite apparent) but I had a STAR instructor following me and he pointed it out literally as I was still gasping for air from launching myself 15ft high and emptying my lungs upon landing.

    Needless to say, now I'm reeeeeally aware of loading and unloading the contact patches over bumps, undulations, on the top of a plateau, etc...
     

Share This Page