I currently have a 2003 400ex. It has A White Bros E-series, uni filter, and a hotcam when it comes to performance parts. The guy I bought it off of put a different sprocket on it(not sure what tooth) to give it more top end. I just do trail riding and smaller jumps. I think my bike lands a little rough and im wanting more power. Would it help to take off my skids or what? Is it worth it for me to upgrade to a 450?

 

You just do trails & small jumps and you want more power? Sounds like you want more quickness, acceleration, bottom end. What do you mean by landing rough? Before you invest in a 450, try a 12 tooth sprocket on the front. $9 from Rocky Mtn.

 

In my experience, the 450R is not a great trail quad. It likes to rev, so when you get into the slow technical stuff, it's just a pain to ride compared to the 400EX which doesn't mind being lugged down.

I forget what stock gearing is, but the Rocky Mountain catalog list stock and has lots of replacements. If you want more power (low end) for the trail and jumping, you can go smaller in front or larger in back...but you will give up some top speed in the process.

As far as suspension, given the age of your machine, the shocks have probably seen better days. My 400EX is an 00, and I put WorksPerformance shocks on it when I first got it a decade ago, and it still lands big jumps like you are landing on pillows! Eats big whoops real nice too!

 

Recon has some good advice.

I wouldn't remove any skid plate protection at all, unless you are only riding on sand dunes. A solid landing on something hard (rock, log, etc.) can create a small dent in the frame tubing, which WILL lead to bigger problems down the road.

Do yourself a favor and beef up the frame and swingarm protection as much as you can

 

Yes, im looking for more bottom end. Im going to try a different sprocket thanks to you guys. When it comes to my bike landing rough. I mean it isnt much better than the Warrior I had when it comes to landing jumps.

 

you can try softing up the front shocks as well as the rear. But its about time you buy some new shocks. If you dont have a lot of money you can put front 450r shocks on and then just rebuilt the stock rear shock.

 

I went down 1 tooth on my front sprocket, and even with 22" tires it was to much. It got wheelie happy, and I couldn't keep the front end on the ground under heavy acceleration. Settled for 1 tooth bigger in back, as a compromise.

 

So a stock sprocket should help the power issue. I have been looking into the 450r front shocks, but how much would it be to have my rear rebuilt? or would it be smarter to put on a 450 rear shock also, if so how difficult is it to swap out for a 450 rear shock?

 

450r rear shock for some reason doesnt work well on the 400. i would either buy a nice used EX shock on ebay, or have yours rebuilt

 

Like it was said worksperformance does what they call new spring kits were you will get a better that stock spring and the stuff to re valve it to the spec's you need. not 100% sure if they have one for the EX but it's worth a look.