i was wondering if anyone put a xr400 cam in their 400ex and if so did it help? what were the powergains? what year cam was it? and what do u think about a high comp. piston? and are tcs shocks any good?

 

I have all of the mods you just mentioned. I just recently had a Wiseco 11:1 compression piston and 2000 XR400 cam installed, and I am yet to get it back. I am waiting on some jets to get the jetting straightened out. Anyway, I'll let you know how it comes out, and what kind of power gains I receive.

The TCS shocks are great. I really like them. I have the dual-rate fronts w/cans, and Works bodies. I've heard that TCS will be using Elka shock bodies from now on. This larger shaft should make the TCS shocks perform even better than before. Good luck.

 

Actually im 99% sure that the 400EX uses a hotter version of the XR400 cam.
I dont think you will see gains.
Let us know.

 

The XR400 cam should add more on mid and top. I believe that it is actually a more aggressive cam than the stock 400EX.[img]i/expressions/face-icon-small-confused.gif[/img] I will let you guys how it turns out though.

 

The XR400 cam is more agressive than the EX cam. The XR cam is not the most agressive but gains are noticable. Sparks has a drop in cam that recieved good reviews. Just a cam mod may leave you wanting more. My advise is get a 11:1 piston, port job, cam, and a 14 counter sprocket. You will be smiling.

Jay

 

I held up on the porting and valve job. I may do those later on. For now, I'm going to see how my machine works with the XR400 cam and 11:1 piston.

 

You may want to check out Thumper Racing @ www.thumper-racing.com.

 

I'm not sure which is hotter, but I dragged a stock 2000 XR400 5 or 6 times with my stock 400EX and it was dead even for the most part. I was even pulling ahead a few of those times.

I will say he weighs about 10 pounds more than me. Maybe it was the rider, but I wouldn't expect much improvement if that's going to be your main mod.


Dave

 

phaskell,

If you drop in the XR400 cam, you probably should consider installing a higher compression piston. This should give good power gains by itself. Probably, with a free-flowing exhaust, porting and polishing, and an FCR carb you should notice some great power gains without sacrificing reliability much. Just my opinion. Good luck.

 

Well, I finally got my quad back today after some jetting troubles (needed a bigger pilot jet). I have to say that the higher compression piston and XR cam made in run like a different machine. It has a lot more bottom end, and will absolutely scream on mid and top. If you are like me and wanted more power from the motor, but didn't want to sacrifice reliabilty much, I suggest that you consider these mods. They woke my machine up. I can't imagine what it would run like with porting/polishing, valve job, etc. Anyway, I thought I'd let you all know about my experience.