Just got back from Glamis where I was able to test the WB slip on, a 13 tooth front sprocket, and the Walker Evans front shocks. For those interested here are my thoughts:

WB slip on has great fit and finish and looks great on the bike. It mounts very firmly and all holes line up. Even the heat shield fits perfectly. The WB silencers are tunable by adding or removing disks. The silencer comes with 9 disks (low by most standards). The sound is throaty and not obnoxiously loud. The limited number of rings helps keep the sound level down but according to White Brothers the more rings, the better top end performance. This seemed to be the case. I noticed a small increase in low end grunt and a definite improvement in mid range power, but high end power didn’t seem to benefit much. I would suspect adding 4 or 5 more disks would give a little more kick to the high end power in exchange for a louder bike. Overall, I think the pipe made the bike easier to ride and noticeably more responsive in the mid range. With the high gearing of the Predator I felt the broader range of power made a big difference. Unfortunately, peak HP at high RPMs really didn’t see much of an improvement. I was using the stock paper air filter with six Uni holes in the airbox and I also upped the main jet to a 155. I will have the K&N filter soon and will probably add a few disks to see if that adds more top end power.

The 13 tooth front sprocket is a must! 2nd gear starts for drag racing are no longer bogfest and 4th and 5th gear are much more usable. The only downside I see is for us Glamis folk who want to make a good showing at Oldsmobile hill. I found myself hitting rev limiter in 3rd through the whoops and shifting to 4th only to have it start dropping in rpms when I hit the steep part of the hill. I’d have to downshift to 3rd and be stuck near redline for the rest of the trip to the top. For me, I was a little quicker with the 14 tooth at Oldsmobile due to 3rd gear being at a better rpm for the hill climb. Installing the sprocket took only 20 minutes and I didn’t even have to remove the chain or a link. I used a 13 tooth from a Honda XR 650L and the fit was perfect.

The Walker Evans front shocks were a nice improvement over the stock Fox shocks. I liked the fox shocks but thought the valving was a little too soft and ride quality over uneven choppy terrain was a little jarring at times. There was also a subtle clunk when the Fox shocks would fully extend which I didn’t care for but I don’t think it hurt a thing. The Walker Evans soaked up bumps, whoops, jumps and chop better than the Fox shocks and travel was supposedly increased by 1 inch. The great thing about these shocks is they are dialed in specifically for the Predator and right out of the box they perform well. I don’t know how these would compare to a set of triple rates from Pep or Works, but I do like how the Walker Evans dual rates feel and the adjustability is quick and easy. Installing the shocks was easy and the remotes have great billet aluminum mounts that fit the frame perfectly. With the silver remotes they match the frame very well. These shocks look great on the bike! I set the preload to zero to give some sag and after some experimentation at the dunes set the dampening to 4 of a range of 6. There are rubber O-rings on the shock shaft that will slide to the furthest point of travel which helps to determine optimum preload and dampening for different terrain. The only bad thing is that heavy riders (250+) will likely find the spring rate and valving too low for motocross or aggressive riding. At 180 I felt the spring rate was very good but the valving was a little on the soft side considering I’m dialed up to a 4 already and will probably use a 5 at the motocross track. Keep in mind, I do ride aggressively and frequently jump the quad so I prefer stiffer settings.

As an added bonus, with the right bushings I can see how the old Fox shocks perform on the 400ex.

 

How did the weight of the WB silencer compare to stock? Did the WB unit have an aluminum heat shield, instead of the stock steel one? It would be nice to compare the ride of the Walker Evans shocks to the fox units with the resevoirs installed.


Ken

 

I didn't have the chance to weigh the 2 pipes, but the WB silencer was noticeably lighter. I'd guess about 4 pounds lighter. It uses the stock steel heat shield. As for the fox units with the resevoirs, I think the biggest difference would be the increased dampening settings and decreased fade (which I seldom encounter). The overall feel of the fox shocks probably wouldn't change that much. I would like to hear some first hand opinions though.

 

Sweet review,great detail.What tyre pressure are you running ? What octane level do you use? Thanks from down under.

 

I just wanted to say thanks Thumper, for the very imformative update. I'm looking for the Walker Evens to arrive on my porch any day, now if the dealer would just call :-( See yea. Happy New Year everyone, Rich