05 cr250r forks question

[flattie]

05 cr250r forks question (Jeremy)??

on my 05 cr250r the fronk forks have a tendinsy to bottom when i over jump or on flat landings(i'm 185lbs geared), the front fork spings on my cr are 44's with 394 cc fluid, mxa sugest either adding 5cc of oil or adding 45's on the springs. mx-tech spring calculator sugest me using small 43's springs in the front. i'm under the impression that if i add heavier springs and lower the oil height then i will add bottoming resistance and make for a plusher ride??? it is time for forks seals so i wanna do sumthing while its apart. after changing the oil in the forks two months ago i added 5cc of oil then another 5cc with no real sucess. the only way i can get it to stop is turn in the compression clickers 2 or more clickes, but will still bottom under hard landing? what would be the best fix for bottoming and still have plush ride

 

[Danger]

I don't know if 494cc is correct. Try 370cc in each side outer chamber with the springs you have. Set comp at 10 clicks out from full in. Use 7.5 weight in the outer chamber, 5 weight in the inner. Make sure there is no air in the cartridges. Then add oil 10cc at a time via the air bleed screws and a syringe if bottoming is still a problem.
For a plusher ride a re valve is in order.

 

[flattie]

ya i typed that wrong.... 394cc sorry, i dont wanna change the wt of the fork fluid. ive done that before on another bike and it slowed down the action of the forks to much in both directions. not an option

 

[Danger]

Sweet as, your decision. What weights are you running by the way?

 

[flattie]

using maxima racing fork fluid 5wt

 

[Danger]

So how will using 7.5 weight in the outer tube slow down your rebound? It will make your oil lock collars more effective on compression and help your bottoming. I thought that was what you were after? :think:

 

[flattie]

i dunno, maybe u got something there??? i'm not a suspension guru... but yes that is what i'm after. guess i need to study my fork parts closer.. thanks

 

[DeVolTeam911]

First off.......where are your clickers at??? Rebound?? Compression?? Are you sure your forks aren't in a bind. A lot of people do not install the front axle and wheel correctly and pull the forks into a bind. The fork then becomes harsh and creates a harsh bottoming sensation which in turn makes people think they are bottoming out when they really are not. Look on your fork stancion. You should have a dust ring around it that your dust seal creates while it travels through the stroke. Where is the ring?? If it is anywhere but all the way down at the fork lug that holds the axle you are not bottoming out. I mean ALL the way. Not 1 or 2 inches above the lug I mean practically all the way to the fork lug. Check this the next time you feel you've bottomed out. Secondly......NEVER EVER take Yamaha Action Magazines advice. That is competely counter productive. Stiffer springs and lower fork oil height?? This will offer a slightly more compliant initial and mid stroke and smooth out mid stroke harshness that pretty much doesn't exist in CR Showa Forks. You WILL still bottom out. You oil height is effective in the last 2-3 inches of the stroke. If you lower you oil height you effectively take away bottoming resistance. DO NOT TAKE ADVICE FROM MXA. That fix is an old fix for Yamaha's with mid-stroke harshness. They just like to apply to every bike they're not happy with and in their minds it fixes the problem. Just like every bike is geared wrong or doesn't have enough power to handle the stock gearing except of course any Yamaha's they test. So they add a tooth to every rear sprocket and claim that fixes it. This is what happens when you get old and slow. Your set in your ways and your simple solutions for your favorite bike is a fix all for every bike. Ok ok.......enough of that.....So where are your clickers??? Let's first get them set in the ballpark for your weight, ability, and type of riding you do. Next your forks should bottom at least once a lap or off big hits. You want to use all your suspension travel. Your bike shouldn't bottom with metal to metal clank it should be a thud or a slight jar where you know you've bottomed. You should feel it in the bike not in your ankles, feet, and wrists. With properly revalved suspension your bike should still bottom, but it will be a nice cuuush...... feeling and it will do so in a controlled manner. Flat landing will almost always cause you to bottom that is the nature of landing FLAT! Once you get your clickers set right, then the next step would be to ADD 5cc of oil to each fork to increase bottoming resistance. If adding oil and slight clicker adjustment doesn't cure it try changing the inner cartridge oil to a 7.5 wt. not the outer fork oil. This will slow down the compression especially on big hits or flat landings where the fork blows through the travel. Changing the outter fork oil will only slow down rebound. Rebound is when the fork is traveling back up. This will not help to slow the fork on the way DOWN. To slow the fork down you will need to change the inner cartridge oil which plays a role in your forks compression or when they are going DOWN. If all that didn't make you happy then by all means get them revalved and start over at the clickers. When you get them back from being revalved they will be setup for you. Valving, oil, oil height. Springs if you need them, which you really shouldn't from the sounds of it. Your clickers will be right in the ballpark when you get them back from the tech. In almost all scenario's 2 clicks either stiffer or softer you should be able to find optimal settings for what ever your situation. Tighter with more jumps=stiffer add two clicks. Faster outdoors= softer minus two clicks. A good tech will make himself available anytime you call him with questions and most offer free revalves within a year to ensure your suspension is working properly and you are happy with it.

 

[gosdrcrgo]

Changing the outter fork oil will only slow down rebound. Rebound is when the fork is traveling back up. This will not help to slow the fork on the way DOWN.

How does changing the outer chamber oil slow down rebound?

 

[James]

How does changing the outer chamber oil slow down rebound?

It doesn't