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View Full Version : Attempt At 8 Second Run Results in running off the track



Husky
Wed Sep 18th, 2013, 11:22 PM
Went to the Wedensday Test n Tune night at Banidmere in hopes of making a 8 second pass down the track. Made some 9.2 passes at 150 mph, so decided to crank up the launching rpm to 8000 rpm to go for a 8 second pass. This resulted in almost flipping the bike over on its back. Tried again with a good successful launch, hit 153.98 miles per hour and went to hit the rear brakes and nothing, when the bike slowed to about 120 mph I sat up in order to try and catch some wind to slow down but by this time I was past the turn off and heading for the sand trap at the end of the track which swallowed my bike up like quick sand.
So went home with only a 9.1 pass and a bruised ego.

Discouraged yes, but will try again before the years out.

FZRguy
Thu Sep 19th, 2013, 02:16 AM
Did it throw you off?

Colorado S14
Thu Sep 19th, 2013, 05:49 AM
There must be something I am missing that causes you to not use front brakes?

Husky
Thu Sep 19th, 2013, 07:54 AM
There must be something I am missing that causes you to not use front brakes?

Alot of drag bikes dont have front brakes. We had two bikes go down this year because of making the mistake of using the front brakes too early. One guy spent several days in the emergency room. Going above certain speeds you do not want to hit just the front brake especially if thats the only one working as the weight transfer will cause the front end to wash out.

Filo
Thu Sep 19th, 2013, 08:41 AM
I really don't understand drag racing (as in, I don't know anything about it; not that I don't like it). What makes the difference in a 8 second run versus 9? Can the difference just be made up in rider skill (which I assume is reaction time, launch ability, and correct/smooth shifting)? Or do you need to just motor up to get faster? On the front brake thing - has anyone tried a single pot front brake setup like they have on little pit bikes? Enough braking power to scrub speed but not enough to flip the bike? I guess you have to hope that a pad doesn't fall out and jam-lock the wheel, but other than that...

vort3xr6
Thu Sep 19th, 2013, 08:56 AM
It doesn't have a whole lot to do with braking power. There is barely any fork travel so when the weight transfer happens, the tire is used as the "spring", which usually results in losing the front.

Husky
Thu Sep 19th, 2013, 09:18 AM
It doesn't have a whole lot to do with braking power. There is barely any fork travel so when the weight transfer happens, the tire is used as the "spring", which usually results in losing the front.

You hit the nail right on the head. My bike has "0" travel on the front forks so any weight transer goes directly to the tire.

Husky
Thu Sep 19th, 2013, 09:32 AM
I really don't understand drag racing (as in, I don't know anything about it; not that I don't like it). What makes the difference in a 8 second run versus 9? Can the difference just be made up in rider skill (which I assume is reaction time, launch ability, and correct/smooth shifting)? Or do you need to just motor up to get faster? On the front brake thing - has anyone tried a single pot front brake setup like they have on little pit bikes? Enough braking power to scrub speed but not enough to flip the bike? I guess you have to hope that a pad doesn't fall out and jam-lock the wheel, but other than that...

Hey Filo, in drag racing as odd as it may seem, when you are running say 12 or 11's its fairly easy to go faster by say 1/2 second or .75 by just doing some minor mods, but once you get below the 10 seconds you are litteraly fighting 1/10 at a time for faster speeds. Its like any racing, land speed, road race etc. The land speed guys can reach speeds up to 200mph fairly easy but than alot of factors come to play going past that. The road race guys can run certain lap times but again once they reach the top they fight for every tenth off their lap time. (Hope that makes sense)

In drag racing, yes the difference can be made up in rider skill, launch ability smooth shifting etc but your reaction time has nothing to do with your end time. You can sit there for five mintues than go and still run a good time. The clocks dont start until your front wheel breaks the beam, of course you would lose the race as the other guy will be half way down the track. Also, yes you do need to motor up to go faster as no matter what your skill level is, if you dont have the horsepower, you'll be limited to only going so fast, so you need all of the above you mentioned in order to run fast times.

As far as the braking, drag bikes are set up completely different from street bikes/road race etc, as some have no suspension at all and most at least have no fork travel. This is due to getting the bikes to have the lowest center of gravity as possible to stay on the track as you are trying to launch a 300 horsepower bike without wheeling and spinnig the rear tire. The rear tire only has about a 5 inch contact patch with the track and the bike usually carries the front tire for the first 60 feet, so you stear it by leaning right or left to keep it straight. Most people think it looks easy but like any racing, the faster you go the harder it gets. Hope my rambling made some sense.

vort3xr6
Thu Sep 19th, 2013, 12:01 PM
I was going to show up last night at bandi but it was raining over by me and I figured it would stay that way. I am going to try and make it out next week.

Husky
Thu Sep 19th, 2013, 02:53 PM
I was going to show up last night at bandi but it was raining over by me and I figured it would stay that way. I am going to try and make it out next week.

Yeah, come on out, the more bikes the better. Just FYI, this Sat. and Sun. they have the CC challenge which is for all street legal bikes, ATV's and snowmobiles. Its kinda fun as you may find yourself racing a atv or a sled.

TFOGGuys
Thu Sep 19th, 2013, 09:42 PM
So what's the diagnosis on the failed rear brake?

Fernman
Thu Sep 19th, 2013, 09:48 PM
Cool. I am trying to get a front strap and links installed so I can head back out there. 9.1 in this weather is good and thanks for the heads up on the brakes. Usually I learn by experience.

Slo
Fri Sep 20th, 2013, 08:49 AM
Glad it didnt turn out worse.... 9.1, damn, I bet your itchin to get back out there once the bike is fixed.

j0ker
Fri Sep 20th, 2013, 09:35 AM
So what's the diagnosis on the failed rear brake?

Yea whats the story here? Glad you didn't get hurt or fubar the bike!!

Husky
Fri Sep 20th, 2013, 01:58 PM
So what's the diagnosis on the failed rear brake?

Hey Jim,
took everything apart, the rear brakes were a little glazed but over all not bad, bled them, no air. Upon further poking around, found antifreeze came out from the over flow jug and appears it sprayed the swing arm thus also spraying the tire which would have caused the tire to just slide. Added another catch can and gonna try again this weekend. Upon checking with some turbo gurus, appears upon the top of the run when making most boost, caused the head studs to streach and caused enough over heating to boil over the over flow. So have a couple of scenerios of what could have happened but nothing definate.

Hey Jim, on a side note the tire I got from you worked great and held all 300 horsepower to the ground without a bit of traction loss.

Husky
Fri Sep 20th, 2013, 02:03 PM
Yea whats the story here? Glad you didn't get hurt or fubar the bike!!

Thanks, yeah about the only thing that got hurt was my ego and just had to dig out a bunch of sand out of the bike. I have a couple possibilites of what went wrong but nothing definate. But this time I have a back up plan, I bought some new Tennis shoes and will use Fred Flintsone brakes if all else fails

Husky
Fri Sep 20th, 2013, 02:17 PM
Cool. I am trying to get a front strap and links installed so I can head back out there. 9.1 in this weather is good and thanks for the heads up on the brakes. Usually I learn by experience.

Hope to see you come out. The lowering strap and links are probably one of the best/cheapest mods you can do not only for safety but performance as well.

Husky
Fri Sep 20th, 2013, 02:20 PM
Glad it didnt turn out worse.... 9.1, damn, I bet your itchin to get back out there once the bike is fixed.

Thanks and yes, cant wait to go try it again. Just got the bike back together and heading for the track. I guess I am just too stupid to know when to give up.