Posts
935
Joined
2/17/2011
Location
Boise, ID
US
Edited Date/Time
11/20/2019 7:20am
Which do you prefer and why? Any advantages to the old Steel feel? Just kicking around the idea of another 2002 green sticker two stroke project here in CA 
If you have pics too feel free to share them! BrAPPPPPP
If you have pics too feel free to share them! BrAPPPPPP
The alloy frame is a tank, has anyone ever seen one break? I cant recall one breaking.
I did own a 14 yz250f and loved the forks. So much that I picked up a set of the SSS and am getting closer to finishing the swap onto my 03 yz250. Currently waiting on a front axle.
The Shop
As to the OP's inquiry: I love my 02'. So much more plush than the aluminum perimeter-framed bikes I've ridden (Honda's).
I was a diehard 06 RM250 guy and swore by that bike but no matter how hard I tried I couldn't get the forks to behave unless revalved and I made some DRASTIC oil height/volume changes those dam forks STILL were harsh and fought diving into any turn plus it was crazy nervous on high speed straights. Dont get me wrong its a brilliant bike but once I got my YZ I was blown away at just how perfect that bike is for me.
Stable yet it flat out sticks into corners like its on rails! Power is flawless, seamless and MEATY. Still has the stock suspension worked on by RG3 from previous owner I recently added my old TooTech sub tank system to it the whole subtank craze was made for the open bath KYB forks that came on the steel framed YZ's only one ride and man is that front end ultra plush now!! Still has the same bottoming resistance. I am going to do the SSS suspension swap sometime this season once I have the $$ to buy the forks its actually cheaper to buy the SSS suspension than do a revalve & springs on the stock stuff but overall for now the stock stuff I have is pretty good. I KNOW how much better the SSS stuff is after riding a few different friends bikes 06 or newer. Truly incredible stuff!!!
Question, are ANY of you that did the SSS conversion also running the SSS shock or was that not really that big of a deal to swap out like the forks??
And to those that ground down the steering stops, wouldn't the 04 clamps work w/o modifying the stops? Forks are the same diameter on the 04's as the SSS forks OR maybe I should look for a set of 05 YZF triple clamps? I just dont feel all that great about grinding material out of the steering stops for strength reasons I know im not gonna maul them but there is an element of strngth incorporated into the camps via the updated steering stop design on the clamps
Yes the 04 clamps work.
You do not modify the steering stop with the 04 clamps, but you do have to modify the front axle spacers. You also have to use a front axle to match the SSS fork year.
The 2002 is a little better on a rough hardpack track, but I don't believe it's entirely the frame.
The swing arm design changed (For flex characteristics) around 2006, the forks on the old steel bike are 46mm vs the 48mm on the newer machines and the triple clamps on the old bikes had the forks mounted closer together (meaning that the triple clamps are about 2mm wider on the aluminum bikes).
I'm actually planning to race my old 2002 a bit this winter... I wouldn't hesitate to jump on that bike since it wouldn't feel any less competitive than my 2010.
Also, the aluminum frame is more durable than old steel frames were. (unless you have a habit of cross-threading and stripping bolts).
I don't think most of us need to worry about the rigidity differences. In my case, I'm a "Johnny Average Amateur" and I don't think I put nearly the load on a chassis that a factory pro does. Most of the "steel is better" talk comes from the fact that Chad Reed, Timmy Ferry, David Vuillemin and others have said they liked the steel bikes better. I'm riding the 30+ class, I'm more worried about chassis setup, geometry, good valving and the lightest bike I can afford than I am worried about frame flex.
Which model bike(s) forks do I need to be looking for? Obviously 06' YZ-YZFs and higher, but am I looking for 250F or 450 forks?
(Sorry for the high jack OP)
Pit Row
I think the forks on the two strokes changed in 2015 to match the later model YZ-F forks. Somewhere around 2012 - 2014, all of the YZ-F models got a smaller diameter upper fork tube where the top clamp holds it.
My 2010, 2011 two sroke forks and 2009 YZ450F forks are all identical. They all have a larger fork tube diameter at the upper clamp than the forks on my 2014 YZ450F.
There was a change in lower fork legs and the axle lugs (as well as the brake caliper) on these forks in 2007 / 2008.
-The four strokes got the smaller fork lugs and slightly shorter lower fork legs in 2007. The caliper mounting brackets changed to match the new smaller fork lugs and so did the caliper.
-The two strokes got the smaller fork lugs in 2008 to match the 2007 four strokes.
If you do the fork swap on an older bike, you'll have to get a brake caliper bracket if your SSS forks are from a 2007+ YZ-F or a 2008+ YZ. You can use just the caliper mount bracket to convert your caliper, or the entire front brake system.
Hopefully I explained that in a simple enough way that it makes sense.
I thought my 06 and 04 were both very good bikes, but I did prefer the steel frame a little bit more.
I seem to remember that Yamaha had a welding issue with some of the early production aluminum frame YZ250F four stroke model.
The long weld down the sides of the down-tube from the bottom steering bearing race would crack and separate catastrophically.
I think they changed the welding process to fix the issue.
in progress picture almost done
before pic locked up and was going to be parted out. gave 325.00
Personaly i think the new frame looks cooler but thats just eye preference.
I'm almost ready with my project: 2003, totally restored. I have KYB SSS, stock and some Öhlins to choose from. I think the 2003 fork felt pretty plush riding around before bying the bike, will give them a try before converting to KYB SSS. Will use the Öhlins TTX rear though...
Vuillemin cracked his 2006+ frame on his YZ250, it broke along the weld under the tank, about two dm in length? After being re-weld, it hold up good I think...
Post a reply to: STEEL VS ALU Framed YZ250s