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'05 forks bottom allthe time

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my forks on my 05 bottom harshly pretty often on any mid sized jump, compression is setup pretty hard and its kinda harsh in breaking bumps. wut do you guys think?

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Depends how much you want to spend?

You can just raise the fork oil in the front.

Get the forks re-valved a bit firmer.

Or you can get Race Tech Gold Valves. 3 times more flow, but a lot more bottoming resistence.

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How big are you? Do the springs fit YOUR weight?

If that's not the issue.......... how much oil is in them there forks?

The last bit: How are you riding? Are you landing on the face of doubles or gettin over them clean? over jumping them?

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i weight~155-160, not caseing on doubles but i am landing on the top of a big table. it has teh stock springs in it the springs seem kinda weak to me but i dont know ive only been riding about 4 months. but when i bottom on the big table its harsh like my helmet has hit the bars a couple times. any more info just ask.

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Well I assume you have never serviced the forks. Manual states to change the oil after the first ride. Inspect your seals and service out the forks.

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The forks are goofed up from the factory. They self bleed to negative pressure as you ride. I am trying the PVC spacer fix now. Also, the stock springs have no preload and are actually a bit short. I put Race Tech springs in mine to get some preload.

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The forks are goofed up from the factory. They self bleed to negative pressure as you ride. I am trying the PVC spacer fix now. Also, the stock springs have no preload and are actually a bit short. I put Race Tech springs in mine to get some preload.

Some how, I just don't think a set of '05 YZ forks are "goofed up" . Ive ridden an '05 YZ125, and those new forks are awesome as far as plush control right out of the box.

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Do you own one or did you just ride one once? Mine rode real well a couple times too.

Yeah, they are real plush and keep getting plusher until there is insufficient damping. Pull the forks apart and the damper rods stop 3-4 inches short of full extension because the fluid has been pumping out each time you bottom.

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Do you own one or did you just ride one once? Mine rode real well a couple times too.

Yeah, they are real plush and keep getting plusher until there is insufficient damping. Pull the forks apart and the damper rods stop 3-4 inches short of full extension because the fluid has been pumping out each time you bottom.

What 05 forks are you running? All except the 250 stroke are the same. The 250 2 stroke has a passive bleed system in them.

If you fill the forks per the manual states with the levels, pump them as directed, you will not have oil problems.

I run stock everything in the forks, use the Torco RFF 5wt 195 inner, 245 outer and never have had issues with what you state. But this is a 250F 05 bike.

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What 05 forks are you running? All except the 250 stroke are the same. The 250 2 stroke has a passive bleed system in them.

If you fill the forks per the manual states with the levels, pump them as directed, you will not have oil problems.

I run stock everything in the forks, use the Torco RFF 5wt 195 inner, 245 outer and never have had issues with what you state. But this is a 250F 05 bike.

I have an 05 250f. I'll bet almost any sum of money that you can come pump the dampers however you like and fill my forks with 245ccs and they will bleed out in a weekend of riding.

Shockdoc seems to think there is a problem also. Tell him he is wrong.

https://thumpertalk.com/forum/showthread.php?t=287097&highlight=KYB

https://thumpertalk.com/forum/showthread.php?t=258347&highlight=KYB

https://thumpertalk.com/forum/showthread.php?t=264819&highlight=KYB

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Trust me, these forks do have their fair share of probs. Mine started out great but like everyone else's they went soft. I added 10mm spacers to the main spring and 4mm shims to the ICS springs and drilled relief holes in the PVC piston. I run maxima 7wt in the inners and 230cc of Mobil 1 Synthetic in the outers. These all helped out a lot but I think there is alot more room for improvement.

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where did you drill your relief holes? That is the part that still baffles me.

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&%$#@!? Why are you using 2 different oils in them? The inner will bleed off the excess fluid to the outer chamber. using different fluids is just asking for problems.

Also dont run anything over a 5wt in them. They get way harsh

For your 245mm comment, that is in the outer chamber. So if you are losing fluid, you most likely need a new crush washer for the bottom nut that holds the inner cartridge. That is the only place they will leak out of the outer chamber unless you broke the lower leg and it is leaking. Seals will not leak that much out.

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For your 245mm comment, that is in the outer chamber. So if you are losing fluid, you most likely need a new crush washer for the bottom nut that holds the inner cartridge. That is the only place they will leak out of the outer chamber unless you broke the lower leg and it is leaking. Seals will not leak that much out.
You really don't have a clue do you? Nobody is talking about losing fluid from the outer chamber.
Pull the forks apart and the damper rods stop 3-4 inches short of full extension because the fluid has been pumping out each time you bottom.
There is no damper rod on the outer tube. Think about it.

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You really don't have a clue do you? Nobody is talking about losing fluid from the outer chamber.

There is no damper rod on the outer tube. Think about it.

Who does not have the clue here? The inner chamber in the manual states 190mm or over the lip. The outer chamber is the 240+/-. So when the previous post stated they were losing the 245mm fluid, that would be from the outer chamber.

If you are putting 245 in the inner chamber, you are way off. Well not if you install the fluid per the manual and stroke the thing properly to bleed off the excess fluid.

Technical term for the lower bolt in the manual is the adjuster. THere is a copper oring that seals it. If you are losing fluid from the outer chamber, that is the most logical place for fluid loss.

IF you are losing fluid from the inner chamber, start by replacing the Orings on the compression dampening assembly. Second, DONT use ATF in forks. It has very harsh cleaners in it. Use Fork fluid.

As far as this being a major issue, not here. If you are not within the designed weight for the fork springs, I can see issues. But everyone here has been running stock springs. I know of one person that used more preload spacers in them that StiffArm suspension setup. Even Josh Hill runs the stock stuff (kid that did the photo shoot on the 2006 bikes for Yamaha).

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you should be just the right weight for the springs. I weigh about 165-170 so I'll give you the specs for my forks. They are set up for woods with some motocross and perform very well on jumps.

Oil-5wt @100mm

Compression-14

Rebound-17

Hope this helps

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Who does not have the clue here?
You don't because nobody is talking about losing fluid from the outer chamber.
As far as this being a major issue, not here. If you are not within the designed weight for the fork springs, I can see issues. But everyone here has been running stock springs. I know of one person that used more preload spacers in them that StiffArm suspension setup. Even Josh Hill runs the stock stuff (kid that did the photo shoot on the 2006 bikes for Yamaha).

It doesn't matter what springs you have, the inner chamber shouldn't bleed out when the forks bottom, but it does, because of the defects listed in those threads. What issue is that exactly if one is not within the designed weight for the springs?

Several suspension tuners are speaking openly about the design defects in the 05 forks, but if you are content with it, fine....I don't care.

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All I know is since I've put the shims in mine it is on rails (like it should be). It is very accurate and doesn't have that vague, cloudlike feel when on the gas.

As far as the original poster's bottoming probs, for his weight the springs should be correct. Add more fork oil, or increase compression clicks or land with the throttle on.

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