Best company to upgrade new YZ450F suspension

All you mentioned are good, depends on your budget?,weight, skill level, type of riding.pro circuit,rg3, mb1, stock with correct springs, set sag.

All are good but you need to be honest with whoever you use so they can tailor the set-up to fit you. You also need to set the sag and learn how your clickers work. It may take a little adjusting to make it feel right. It also may need a little break in after a revalve.

I spent all of 2010 and the first half of 2011 dialing in the suspension on my YZ450F with the help of a guy from Nashville, IL and am still using that same setup so, here's my 2 cents on what you should do...btw, Im 5'10" 175 pounds and a local A/+25 rider... My biggest complaint with the stock suspension was that the rear end would kick around coming into rough and rutted corners and made it very hard to keep decent corner speed and stay in ruts. Here's my theory on what the stock setup's issues are: The front fork springs and valving are too soft which causes the front end to ride low in the stroke and be kinda harsh especially when coming into rough corners. The rear is just the opposite, its sprung ok for me but rides too high in the stroke and when coupled with the soft front end, the rear end of the bike becomes unweighted when braking and thats when it starts being unpredictable. The solution: stiffer front fork springs to keep the front end up and a better (stiffer) valving set up. The rear end is a little trickier, you really need to do one of two things to make the rear end ride a little lower. The first is a llinkage arm from Ride Engineering, Pro Circuit, etc. which is not cheap, or what we did which is install a 3?mm spacer in the shock to essentially lower the rear shock just a tad. By stiffening the front and lowering the rear just a bit, the bike rides straight and level and is waaay more balanced. We've had at least 6 other new YZ450 riders with skills ranging from vet novice to Pro License holding riders use this set up and everyone seems to really like it. The name of the guy is Frank Bartolotta from Smart Suspension, he's a good dude and won't try to sell you a bunch of gimmicky stuff and is pretty reasonably priced and is very easy to deal with if you have an issue. Other than him, I think Pro Circuit and Enzo use a similar set up. Again, just my 2 cents. The other suggestion I have to anyone looking to have their suspension revalved is to know what you want to gain. And by that I mean you should really know what you want improved, what it does that you like and dislike. You'll be much happier in the long run if you have a goal of improving a certain aspect of the suspension instead of just going to someone and saying "here, make it better".

Just to muddy up the waters you left out Joe Gibbs Racing.

Get the right springs (Front & Rear) for your weight to start

I am more of a fan of local then Socal companies. I have had two suspension done for Socal and they were really poor for the dirt I ride in. Did fine in the dry, square edge. I now have a guy that is in the same state and does his own valves....much more suited for my terrian. I just read in the gossip boards about a new engine mount by lightspeed (I think) that helps with push...of course, there was some arguing over how well it works...but they argue over everything in that forum!

Factory connection, their testing is unmatched and their service is second to none

G-force suspension has the yz450 figured out.rear is very stable even at 102 race sag.and not lowering the shock.

I sent my sons stuff there today. We are very excited to see how it is.

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