On page 67 or July's 4 wheel atv action it states that Duog Gust uses +3 +1 a-arms. No my question has two parts: 1) are these legal? Because every other racer I've seen runs +2. 2) Can you put +3 a-arms on a 400ex and remain legal?

Thanks

 

You can use any length you want as long as the width of your quad does not exceed 50" that is AMA rules. With 3+1 a-arms you need to run a wheel 5" in width with a 4" backspacing to be legal on a stock frame. I think Doug Gust uses a narrow Laeger frame with the 3+1's and a wheel that is 5" in width with a 3" backspacing.

 

Snell,

Thanks for the info, but I have one more question. What is backspacing? I don't think you're talking about offsetting the rims, so just not sure. Would like to know because I'm about 6 months away from buying new a-arms, front shocks, and a rear axle for my 400.

 

Wheel offset and backspacing are the same thing.

 

I believe +3 on an EX is equal to +2 on an R.

 

So when buying arms for a 400ex it's better to go with +3? I'm about to make this purchase and do not want to do the wrong thing. Regardless of brand, what is the best setup on a 400ex for mx? My wheel offset currently is 3in 2out or -1. I've measured the total width and it is around 41 - 42 inches now. I'm thinking +3 arms with the same offset, but now sure if the longer arms will dig into the corners. Would I be better off with +2 arms and a larger wheel offset?