Is it possible for the swingarm to hit the airbox at full compresion on the predator? I had one of the brackets that holds the airbox to the subframe break in half. It broke in half at the screw hole on the top side were it bolts into the subframe. Also on the other side the screw that holds the bracket to the subframe broke. It snapped its head right off. So this leads me to think that maybe the swingarm hit the bottom of the airbox pushing it upwards and broke the screw head and bracket.? Ah heck maybe I should just put a clamp on K&N on and then I won't have to worry about it at all.

 

Ixnay the box and call Hyper Racing for $23 the RU-1770 is the ticket. The K&N 62-1010 works for the crankcase breather.

 

i dont think that that is what is happening on your predator if you look on your airbox lid the seat is hitting the lid pushing it downwards thus not letting it move upwards to snap your screws

 

My swingarm cracked my airbox also. It was where there is a little rise on the swingarm. It deformed the airbox causing the filter not to be seated and I ingested a little dirt...nice. I cut a portion of the airbox out where it hit and haven't had a reoccurance. If someone doubts this could happen, measure the shortest distance between the swingarm and airbox. Mine was around 8" with no sag. This was not to far in front of the axle where 11" of travel should be present. The math is close. Note: This is probably due to the constantly bending rear shock bolts! What the heck is this. My rear shock bolts bend losing about 1/4" of rear frame height and probably gave the swingarm enough closure to hit the airbox. Oh Well. I'll keep on top of the 7/16" shock mount bolts and keep replacing bent ones.

 

Hmmmm, I have a few suggestions, but I'm waiting for you to answer a PM I sent you.

 

When I talked to the guy at Walker Evans about the spring rates on my shocks awhile back he told me that when they were doing shock testing with Polaris test riders last summer they had problems bending shock mounting bolts when running the Foxs. He also said they bent a couple shafts on the Foxs but didn't have any problems with the Walker Evans shocks. He said when they bent the bolts & shafts they were hitting a kicker type double and casing it on purpose to see how much abuse they would take before something broke. He said the test riders were flat out nuts.

 

Excellent...you confirmed what I think is the problem. In woops or sharp edged bumps it is too easy to bottom the rear. I had the back revalved with more high speed dampening and a more progressive valve stack. My low speed damping is actualy a little softer now and I feel this combo has given me better performance in stutter bumps, braking bumps ect.. The rear end seems to follow the ground better than the stock valving but it still bottoms as easily. Could a slightly higher rate rear mainspring be the ticket? I read a lot of dirt bike mags and it seams you cannot ignore those spring rates and think the valving will take care of it. Let me know as you seam to know about this. I would prefer to not have to go out and get a Walker Evans shock but if would if I had to to solve the problem. I am pretty happy with the fronts.

 

JJ, I'd call Rath for the spring info, he's got the MX knowledge to get you setup. For the shock bolts, step up to either grade 8, or go with my fave Mettec.com for some Titanium units. A fellow racer bought the Rath dual rate springs, and loves 'em.

 

Yep, call Rath. I've talked to them a couple time on the phone and they've always pointed me in the right direction whether I bought something from them or not.