Straight Line braking issue

joey marshall · Joined: 20 Mar 2007 Posts: 59

The kart kicks the rear end to the right under hard straight line braking.

Why? Could the axle be twisting and unloading?

The kart was scaled and all 4 corners were within 2lbs of ideal weight.

Thanks in advance

al nunley · Joined: 13 Nov 2006 Posts: 3038

Cory Milne · Joined: 10 Aug 2009 Posts: 99

change your brake bios and bleed the breaks

Rodney Ebersole · Posted: Wed Jul 11, 2012 7:47 pm Post subject:

Maybe it's the load developed from the left foot on the brake pedal.
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joseph hollinger · Posted: Wed Jul 11, 2012 7:50 pm Post subject: Re: Straight Line braking issue

Randy Mckee · Posted: Wed Jul 11, 2012 8:05 pm Post subject:

Rodney Ebersole · Posted: Thu Jul 12, 2012 6:25 am Post subject:

I read the post as he was working with a rear brake only problem.
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joey marshall · Joined: 20 Mar 2007 Posts: 59

Rodney,

You are correct. It is a tag kart with rear only brakes. We did have to put some brake fluid in it after a day of running but I didn't see any fluid leaking from the system. We did have some smoke coming off of the brake rotor when we came in on one session. The kart is a Shockwave with Willwood brakes. I have a maranello chassis with brembo brakes and don't experience this issue.

Richard Thoms · Posted: Fri Jul 13, 2012 7:22 am Post subject:

What direction is the upcoming turn? Does it kick right both into left and right turns? It does not take much of turn-in to upset the kart under very heavy braking especially if you have lots of caster and wide front end.
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joey marshall · Joined: 20 Mar 2007 Posts: 59

The corner is a 90 deg left and yes the rear is kicking out to the right. We actually brought the fronts in to 45" from 45 1/2" and the caster is set at the medium setting which is working pretty well on most of the turns. We tried max caster but the kart was slower.

Richard Thoms · Posted: Sat Jul 14, 2012 9:20 am Post subject:

So you are coming up to turn left and the kart is turning right on braking? (or the rear is going right - kart turning left?)

I wonder if it could be a stagger issue. Is this always a problem or just on recent set of tires? Maybe try swapping rear tires left/right and see if it kicks in the other direction??
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George Young · Posted: Sat Jul 14, 2012 8:28 pm Post subject: brake problem

Make sure your chassis is squared up. Measure from the inside of the axle to the center of the spindle with the front steering pointed straight ahead. It should be the same measure on both sides, and of course have the proper toe setup. It could be a little out of square and when the brakes are applied the back end squares up???
george Y

Chris Livengood · Posted: Wed Jul 18, 2012 9:10 am Post subject:

Widen rear track, reduce caster or jacking. Could be a driver anomaly.
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Paul Makarucha · Posted: Wed Jul 18, 2012 9:35 am Post subject:

Walk out on track, place level in same place the rear tires would be when you start braking, watch the bubble go to the right side of level.
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Mike Goebel · Posted: Wed Jul 18, 2012 11:32 am Post subject:

Try Braking in a straighter line!

Mike G.
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