I'm Going for It!!! Tips/Comments Welcome!

My front and rear Geomax MX51's have arrived...and they look MEAN!

Due to arrive tomorrow via UPS...

Tire spoons and bead tool

Fork wrench and compression socket

Amsoil Shock Therapy (qt of light, qt of medium)

Fork and Shock springs

SDG tall seat on backorder :/

Got the rest of my ordered items today (except my tall SDG seat :cheers: )

I'm telling you...the 6.2 shock spring I ordered from Diverse Suspension Products (aka Diverse Manufacturing) is HEAVY AS HELL! Not that it matters to me at all. An extra pound or two isn't going to have any real effect on a total package weight (me and the bike) of just a hair south of 500 lbs!

Quite a bit more material in this heavier spring (5.5 to a 6.2)...and my stock spring was titanium...so I guess that makes a bit of difference! :moon:

Mounting tires tonight (now that I have two new tire irons and a Tusk bead tool). Geomax MX51's front and back. Rear is 120/80/19...that beeotch is PHAT!

The Ti spring is over 3 pounds lighter than an equivalent steel spring. Very nice if you can use it.

Interesting, I was super lost for a second, in 2009 the 250f went back to the steel spring and I thought the big bike did the same...obviously not. It's nice to be reminded that the titanium spring was standard on that year. If you stick with the changed spring I would imagine that you will be able to recoup a chunk of your upgrade money by finding a new home for the ti spring. Your project is looking great by the way. Keep up the good work.

looks good. i need to do all that mine.


Okay, so my service manual says to measure the length of the uncompressed shock spring (it's 10.5"). It says the appropriate range for pre-load is between .06" and .51" (so looking for an overall "compressed" measurement between 9.99" and 10.44").

I'm 6'4", 245 lbs. and have changed the shock spring from the stock 5.5 (titanium) to an aftermarket 6.2 (steel).

I've set the compressed length of the spring right about in the middle (overall measure of 10.25") to get started. From there (once I have all my other mods done), I'll measure my race sag to make sure it's between 90mm - 100mm. If it's not, I'll adjust the spring pre-load. Once I get 90mm - 100mm race sag, I'll measure the static sag and see where it is (hopefully it'll be between 25mm - 35mm).

Once that's done, I'm going to set my ls/hs compression in the middle (ls = 10 of 20 clicks out, hs - 1 of 2 turn out)...and set rebound a little tighter at 7 of 20 clicks out (thanks mog).

Going to use the same set up in the forks (went from .47 to .50 springs)...middle of the road in compression, a little tigher on the rebound (8 of 20 clicks out).

Also on the forks, I'm using Amsoil Shock Therapy...using 5wt in the inners and 330cc's of10wt in the outters (-20cc's than spec for a plusher feel while maintaining bottoming resistance - thanks gray).

Is anything written above too far off the mark? As always, your input is much appreciated! :moon:



One thing that really helped me on my bike (I'm 6' 4" as well) was a new set of pegs that relocates the spring from the bottom to the top which sets your pegs down and back about an inch. It doesn't seem like much but it sure helps. Plus the the teeth are replaceable. I cannot remember the brand but I will look when I get home.

I run those pegs as well. They are the Fastway pegs and come in 3 styles. I went with the F3 and I am happy with them. Thumpertalk store isn't showing them available for the 09 but Fastway is on their site so all you would probably have to do is call thumpertalk and verify they are the same parts # which I think they are.

also, this was posted on the Fastway site so if you go with the pegs, beware:

NOTE: Pegs will not mount in lowboy position on 2006-09 YZ/WR 250F/450F 4-stroke models. Requires Low Boy Mount kit to install in lowboy position. Low Boy Mount Kit will not work with WR models.

Having said this, I was able to mount these pegs in the lowboy position on my 06' without the kit using a modified stop screw on the peg. Let me know if you need anymore info on this.

Thanks for the heads up on the pegs. I think those are next on my list.

My re-built is complete. Changed springs/oil in the forks. Wasn't too bad. I put 5wt in the inners, and 10wt in the outters...can't wait to get the bike to the track to see how she performs!

I was going to change my tires (new MX51's)...but once I got the swingarm/linkage back on and the forks done...I couldn't help myself. I had to sit on her with the stiffer springs. Feels REEEEEAAAAAAALLLLLLL good. I'll post some final pics up later this morning...and this thread will be kaput!

Everybody and anybody who posted...and helped me out...many thanks. Couldn't have done it without you!

uh...changing tires is now my worst hated thing to do in the world...ever.

I was waiting for this post. :moon:

What da problem is?

tires, rims, tubes, wheel lock...getting the old tire off, getting the new tire on, scratching up the edges of my pretty black Excel rims...

That's really the only problems...

Something that really helped me was a third tire spoon and taking my time with the first few tires. Things will get better but those first few can be tricky.


Well...I mounted a new rear tire today. It was a lot easier the 2nd time around! These MX51's look SICK! Can't wait to try them out! Forest Glen MX is open for practice today (even though it's probably under 50 degrees down there)...but it's too damn cold to ride! Hell, it's too damn cold to go outside! :cheers:

Again, thanks to everyone who provided input to my maintenance/mod project!

You know I changed the oil in the forks (and put in heavier springs)...they feel great while sitting on the bike, and compressing them while standing still. If I happened to have screwed up and got some air in the inner cartridge, how would I know? In what way would the forks perform poorly? Would they just blow through the stroke because the air is getting compressed easier than oil would?

Keep warm folks! Down here in Tampa, it was 26 this morning! It's gotta be cold up north! (Supposed to warm up this week, and I'll be riding a fantastic MX track next weekend...temp should be near 70! :moon:)

I am from western PA and it was -2 degrees F. This morning.

Ah yes...I remember those frigid conditions...I used to live in western Maryland. Used to ride Gettysburg on my ZX7 Ninja...during the summer, of course! It was awesome! But now that I'm back into MX, I'm DAMN glad I moved to Florida!

I got the opportunity to ride Forest Glen MX this weekend. Suspension mods were worth every last penny! The bike worked so well everywhere...especially the sand/sand whoop sections that were kicking my a$$ so hard before. I didn't get an opportunity to push the bike real hard, as I got to the track late...only got in a few sessions (about 10 laps total), and I wanted to take her easy since I'm a novice wrench (didn't want any high-speed surprises!).

A month ago...after I changed the springs and set the sag, I was thinking DAMN...THIS SUSPENSION IS STIFF! But riding it changed my opinion. It's stiff when I'm sitting on it in my garage...but it's butter at the track! The bike rides so much higher in it's stroke, it's just a night and day difference. I never knew suspension could be this good! YEAH BABY! :bonk:

Oh, and the new tires helped in the sand just a bit too...heh. :ride:

Special thanks to all those that helped me through...doc, gray and others, really appreciate your experience (:lol:) and your willingness to share it!

Sam :D

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