Can anyone tell me what they have their a-arms set at for caster, camber, and toe in and toe out for a race aplication on a 400ex? I have 2+1 a-arms and currently have the camber at 4 degrees and the toe at 1/2" out. not sure if this is the right set up or not and do not know what to set the caster at. Any help would be appreciated. Dave

 

doesn't anyone in here have aftermarket a-arms? If so how did you set yours up?

 

Out of topic, but what Brand of A-arms do you have on your 400EX, I have been looking for any +2+1 and I can not find them, I only find +2+0.

THANKS

 

While I have a 250R, it is very similar to the 400ex in the a-arms. I just put on Leager +2 arms this past week. Here is what I set everything at.

For the toe, I set it at 1/8 of an inch toe in. I use the string method (from my old race car days) to make sure all four tires are running straight. Then I put a 1/16 on each front.

For camber or caster (not sure which is which, but the one that makes the wheels / \ or \ / ) I set it by eye. I think I will go with a little more angle / \ than I have now.

How do you measure the camber (/ \ angle)? I have a few ideas, but was wondering how do it exactly.

 

Measure the camber (tilt) by setting the quad with good tire pressure on flat ground and placing a carpenters square against the tire and ground. The square will touch the lower edge of the tire and you measure the distance from the square to the upper portion of the tire. For location I measure the distance to the upper portion of the tire at the same location the square is touching the lower portion (not sure if my description makes sense). Baldwin Motorsports recommends setting the camber at negative 5/8" without the Pro-trax spindles. Some ball joints will break if the tilt is more than 5/8". I have my LSR A-arms set at 1" tilt in on each side and I checked the ball joints for binding by unhooking the front shock and moving the a-arms through the full range of travel. If your ball joint starts binding before reaching full extension then you will have problems.

Caster is the angle of the upper ball joint in relation to the lower ball joint and most people are better off leaving the standard settings the a-arms came with. I have never experimented with caster.

I have the toe-in on my 250R set with negative 1/4" (1/8" on each side). I believe most people run between 1/8" and 1/4" for motocross, and Baldwin recommends 1/4".

 

The settings for the Camber ( The amount of degrees that the tire and wheel is tilted in at the top in relation to the bottom of the tire) for mx are recommended at negative 4.5 degrees with a max around 6.0 degrees.

The settings for the Caster ( The amount of angle that the spindle has in relation to the vertical centerline of the wheel, if the upper ball joint is farther forward than the lower ball joint it is said to have negative caster.) The greater the amount of positive caster the more stable it will be at speed. The less positive caster, the easier it will steer and the quicker it will turn. As the spindle is laid back, the tire has to lay over more making it quicker and easier to turn.
The recommended caster is positive 4.5 degrees.

Toe-in should be set at 1/4 inch.

To set the camber and caster you need a straight edge and an angle finder to make sure of your settings. Lay the straight edge on the wheels and put the angle finder on the straight edge. To get the caster lay the straight edge against the ball joints and measure with angle finder.

 

Thanks for the information. I am going to set my toe in as recommended. I am also going to change my caster settings. Right now i have positive caster. I measured my camber settings with a tool you can buy at an auto parts store. It basically looks like a carpenters square but it has bubbles like a level would. When you hold it up to the wheel it reads in degrees for front alignments.

 

Thanks for the information. I am going to set my toe in as recommended. I am also going to change my caster settings. Right now i have positive caster. I measured my camber settings with a tool you can buy at an auto parts store. It basically looks like a carpenters square but it has bubbles like a level would. When you hold it up to the wheel it reads in degrees for front alignments.

 

KYRaptor,

I'm about 98% I've seen your quad at the races. I think I remember you being at Echo Valley, and whooping up on everybody. Well, have you raced at the track in Nebo? Western KY Supercross? Which do you like better? I rode at Nebo's track last Wednesday, and plan to be there tomorrow to practice. It's a lot different from riding at Poole. Thanks.