400ex a-arms

[vroomy]

Ok I've read plenty of threads stating that 400ex arms work on the 250R with some spacers, but what I'd like know is are the arms made with the exact same geometry? Especially aftermarket? Reason I ask is I was speaking to Duncan Racing and they told me they are different design

[Burns310r]

Im running them on my bike right now. They work great. The geometry difference most likely is in the spindle. You can run a 250r spindle, but the 400ex one is supperior. But with 400ex spindles you have to run the crappy 400 ex brakes, buy expensive adapters to convert to 250r brakes or run yfz 450 calipers.

[rk88r]

I think the only worry is adjusting the camber. The upper balljoint will stick out of the arm a hair more.

[vroomy]

What about the 400ex shocks? Mainly long travel, are they the same length and similar valving?

[deathman53]

every a-arm requires a-arm different length, leverage ratio and valving is specific to rider wright, type, skill level and even your rear shock settings. You can't bolt on any set of front shocks and expect them to work well.

[chopp124]

Ok I've read plenty of threads stating that 400ex arms work on the 250R with some spacers, but what I'd like know is are the arms made with the exact same geometry? Especially aftermarket? Reason I ask is I was speaking to Duncan Racing and they told me they are different design

u can run them the only difference is the upper arms is longer so u cant run the 250r spindals, u will get positive caster. the shock mounts are in a different location so u have to favor the front of the bike. the shocks are exactly the same if u ran a 250r or 400 ex a arms i have 7 bikes and 4 are 250r arms 3 are 400 ex arms. i have run 400ex brakes for years never had problems but its preference i guess. ill try and post some pics if needed.