How do I make the 02 YZ250 Handle???

[Studboy]

I took my 02 YZ250 to the MX track yesterday for the first time,  and I'm going to have to say that I was disapointed in the handling and suspension.

The bike has stock suspension and the whole bike only has about 10 hours (or less) on it.  I weigh about 160 lbs. geared weight.

The problems I am having are:  1.  The small bumps beat me to death,  it feels like the suspension is barely even moving on small bumps (especially the forks).   The forks are not binding (that's the first thing I checked),  there is no air buildup in the forks, and I am pretty sure that they are not packing.  I tryed going out about 6 clicks on the compression and that did very little,  I haven't touched the rebound yet.  The forks are sitting flush in the clamps.

2.  The bike would not take corners well.  The front end really wanted to push bad and slide out (this was in both loamy and hardpack conditions.)  Even when I sat on the tank and weighted the outside footpeg heavily my friends XR250 was outcornering my bike. :eek:   The bike does feel good landing from jumps however.

The shock feels OK,  I did back it out 2 clicks on the compression and lessen the rebound (turn in) 2 clicks because it was swapping a little bit.

So,  what do I need to do to get this bike setup right?  Should I try and raise the forks in the clamps 5-10mm?    The bike feels very good in the sand dunes (no square edge or small bumps,  different turning.) but on the dirt I am getting beaten to death.  Suspension is not my strong suit.

Thanks guys,  I appreciate it. :worship:

 

[shockdoc]

Yes, raising the forks up to about 10mm's will help/


doc

 

[01HondaCR]

If the bike only has 10 hours on it then maybe the forks arent broken in yet. I'm just taking a wild guess.

 

[Studboy]

01HondaCR, that may be part of the problem. The forks have gotten noticebly softer since I've been riding it (jumping it) lately. But I think that now they have loosened up, but I could be wrong.

 

[dbrace]

Forks harsh but bottom? Shock harsh over bumps exiting corners? = Revalve

 

[MX-727]

The stock springs are for 180lb rider w/o gear. That may be causing part of your problem. I went to heavier springs for my 190-195 lbs before I ever rode and didn't notice the problems you're having.

 

[marcusgunby]

The recent YZs have IMO come with valving that was designed by a weirdo- i dont believe you will get a good setup from the forks without revalving-they have too much midvalve lift and too stiff a base valve-just like recent KTMs-people have similar complaints on the KTM-not a coincidence.

 

[Studboy]

marcus, you may be right. I am going to try and lower the forks in the clamps a bit and see if that helps with the cornering at all. The cornering problem bothers me more than the small bump absorbtion (or the lack thereof) does! The cardboard seat doesn't help at all either.

If I need to, I may end up getting the forks revalved. The shock feels decent though.

 

[bclapham]

Originally posted by marcusgunby
The recent YZs have IMO come with valving that was designed by a weirdo-

Marcus: you never told me that you had been designing YZ forks! :laugh:

 

[Studboy]

LOL!!! If I was to get them revalved, it would probably be by MX-Tech.
What kind of $$$ would I be looking at? Would I need new springs (they are .44, the spring generator reccomends .426)?
If I understand right the cost for revalve and installing piston is $245, but does this include new seals, oil, labor, etc? I am confused!!! My bike already has pretty much all the motor I could ask for, but the forks need some help so soon I may do something about it.

 

[marcusgunby]

LOL bruce, I bet if i gave ross all the yz shims he could come up with a better stack than std.Dropping the forks will help it corner and it will put more weight on the front-thats about all you can do apart from getting the correct springs-IMO however spring rates are not as critical as people think(notice i said as critical-they are still important)i just dropped my fork springs from a std 0.42-0.43(depending on who you trust) to a tested 0.40 and the difference in feel wasnt much.

If i was to choose i would have good valving and bad springs than vice versa.

 

[Studboy]

Marcus, what do you think about the stock shock on the 02 YZ's?
It feels decent to me, but it's hard for me to tell when I'm feeling every bit of the track!

 

[marcusgunby]

I can only give comment on the 125 as thats the one i rode but it felt stiff and tall-it kicked in breaking bumps-to its credit it(the shock) felt better than the forks.I believe Yam made the linkage more progressive than the 01 and this gives a harsher feel.Alot of tuners have had problems getting the 02s to handle well.My KX has a similar linkage ratio and it can be made to work well, but you have to be a bit more radical in the valving.

This topic reminds me of sundays race-i was chasing a guy on a 03 YZ125-he was getting tired as it was near the end of the race, he hit a few good breaking bumps and learned what headshake really meant-lock to lock a good few times.I was thinking how the 03YZ was setup badly and his bike proved me right.

 

one major problem with fixing the forks is you may notice the shock alot more:scream:

 

[bclapham]

:worship: wow, not only does this guy have time to worry about his own bike in a race, he can even spare the time to worry about the bikes he is racing against, could you hear his bike pinging as well? :worship:

and i thought i had obessions! :)

back on topic, did anyone see reed in the whoops at vegas- his forks hardly moved but all the work was done by the shock.

if i had the choice of good forks or good shock, i would take the forks everytime.....thats what knees are for, right?;)

 

[Studboy]

Marcus, you're review is really reassuring!!! ;)  
I am no pro MXer so I want the bike to handle well on my level.  The only think the forks have going for them is a good feel under hard jump landings.

What are the stupid RAGS thinking??? They never mention these things! :uh:

At least the motor is good, LOL! :cool:

 

[marcusgunby]

Brucey boy ,One thing i have never understood is how the KTMs look good on the track, and yet when i ride one, it feels like its got 20wt fork oil and a shock made with lard as a damping medium.

 

[DEANSFASTWAY]

Guys,The 03 stack is even firmer. Try switching out the stock oil for some 5wt maybe with a bit higher level or jump in there and take out some mid Speed on the base valve or switching the midvalve around like Jeremy does . Or best yet just put them in a box and adress it to Wilkeys shop he does a trick midvalve conversion that feels like butter . Talking about Stiif front soft rear , One of my buddies rides 125 nationals and he tells me that all the outdoor bikes are stiff front soft rear (you can hit anything at speed ) and SX bikes are more balanced overall . It appears as though RCs SX bike is kinda low and soft in the rear though.

 

[Studboy]

I was wondering, what would you recommend to do Jer?
I weigh approx 160-165 lbs geared, and I am a novice level motocross rider/off-road rider.

 

[SpectraSVT]

I'm chiming in abit late here but my 03 took 3 months to break in. The suspension was almost unbearable on rough tracks. I felt everything and the bars would shake out of my hands. I was rather disappointed with the harshness of it when I thought it would be better than my 93 RM. After 6 months of riding I think they are finally broke in and its time for new springs.

I'm a big guy at 6'3" 240lbs and the bike was way too stiff for me...can't imagine what it must have been like for you.

 

[Studboy]

......."FEELING THE TRACK" took whole new meanings. Not just from the bumps, but from how many times I washed out in turns. I feel the same way, I was expecting it to be a little bit better than my 94 KX250 (It's not right now, I was much faster on the KX.) :( :( :(

 

[russ17]

Spectra 6 months to break in! maybe its just time for a service. Also some times the active valve shims get stessed in wich the forks will soften quite a bit

 

[flynbryan]

If you wait to long between oil/fluid changes the fluid deteriorates, and causes the bike to start bottoming. It happened to me. I even bought went as far as buying a new rear spring because I thought I had gotten to aggressive for the std. I finally changed the fluid, and guess what? The new spring was too stiff. Argh!! So its sitting in my garage now. Just trivial background. I guess the point I was trying to make is that fluid break down greatly contributes to how the suspension reacts/feels. Its amazing how much better it works when you have quality fluid. So I would strongly advise getting a fluid change if you have yet to do so.

 

[SpectraSVT]

Well I'm still running the stock fluid. I have ridden the bike every weekend since November. The bike was always harsh then it suddenly starting bottoming out. I'm trying to get new springs for my weight so I will change the fluid out then. Any reccommendations? and how long does fluid last?

 

[flynbryan]

The owners manual reccomends some ridiculous time span. Its 7.5hr actually. I find that a little often. I'm no suspension expert, so I wouldn't really want to give you a straight answer for that one. I think I might change mine every 25hr or so. But our suspension experts may be appauled by even that long. I don't know for certain. Maybe Marcus, bclapham, or Jer could chime in w/a respectable time span? What do you think guys? How long do you wait?

 

[bclapham]

Originally posted by flynbryan
Maybe Marcus, bclapham, or Jer could chime in w/a respectable time span?

talking about standing on the shoulders of giants, i dont think my name is really worthy to go between those two. :worship: or maybe i am the rose between two thorns!;)