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05 YZ250 - What else to upgrade front end?

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Hey guys, 

I picked up a set of 06 YZ250F forks and they'll be here next week. 

I read other threads on it, but most are for the steelies. 

Can I simply use the same triples with no issue, or do I need 250F triples and steering stem? 

Also, is there anything different between the current AOSS fork lugs and the SSS ones or will everything mount right up?

Thanks for reading!

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I believe you will run into geometry issues with the 250f forks as they are quite a bit shorter than the yz250 forks...

Use partzilla to see if the axle and spacers are the same as your yz. Most likely you can use your clamps and machine one of the spacers to center your wheel. There are threads on this.

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2 hours ago, LumberjackLloyd said:

I believe you will run into geometry issues with the 250f forks as they are quite a bit shorter than the yz250 forks...

Use partzilla to see if the axle and spacers are the same as your yz. Most likely you can use your clamps and machine one of the spacers to center your wheel. There are threads on this.

From what I was told, they should be okay as they are, but I'm not sure if they are fine with the 05 clamps since they are different than other years.

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From what I was told, they should be okay as they are, but I'm not sure if they are fine with the 05 clamps since they are different than other years.


Again, they are shorter by a good bit and I would advise against them.

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rear shock is also changed after 2005

Shock shaft went from 16mm to 18mm. The 18mm shaft is stronger, but has more seal friction and the added strength is not needed.

YZ's went back to 16mm in later years. It is more lively with less friction and easier to tune as the shaft displaces less fluid during stroke.

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2 hours ago, LumberjackLloyd said:

 


Again, they are shorter by a good bit and I would advise against them.

 

They should slide in though? I'm not using different triple clamps, but I'm thinking the axle may need spacers since the forks are different? Or maybe they don't? 

Lots of threads and it seems no one can come to a concensus of what fits with what mods :facepalm:

Also not changing the shock, I'm happy with it and it's not too bad, but the forks are way too harsh for my liking no matter how I adjust them.

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1 hour ago, MaybeMe said:

They should slide in though? I'm not using different triple clamps, but I'm thinking the axle may need spacers since the forks are different? Or maybe they don't? 

Lots of threads and it seems no one can come to a concensus of what fits with what mods :facepalm:

Also not changing the shock, I'm happy with it and it's not too bad, but the forks are way too harsh for my liking no matter how I adjust them.

Have your aos forks been valved and sprung for your riding and weight? aos forks can be made to work VERY well. The major advantage to sss is the larger base valve which controls a larger volume of oil better; for instance fast riders that use lots of stroke very quick.

To get a set of SSS forks, rebuild them, get the clamps, axle, spacers and be in good riding shape, you will have at least $1000. Ask me how I know... I would not invest this much for the shorter 250f forks.

I would wait and pull the trigger on a set of forks and clamps off of a later year yz250 2t or 450f (used the same forks some years with different valving).

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1 hour ago, LumberjackLloyd said:

Have your aos forks been valved and sprung for your riding and weight? aos forks can be made to work VERY well. The major advantage to sss is the larger base valve which controls a larger volume of oil better; for instance fast riders that use lots of stroke very quick.

To get a set of SSS forks, rebuild them, get the clamps, axle, spacers and be in good riding shape, you will have at least $1000. Ask me how I know... I would not invest this much for the shorter 250f forks.

I would wait and pull the trigger on a set of forks and clamps off of a later year yz250 2t or 450f (used the same forks some years with different valving).

Not much of going back now since I bought them, but I paid $350 shipped a pair of them that have 3 hours on their last service with oil, bushings, and seals. The seller had previously used them on his '04 with no issues.

I figured that rather than spend the money to have the stock forks revalved and sprung, I still might not be happy with them, and everyone praises the SSS and how much better it is, so that would be a step in the right direction.

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Received the forks today!

They look like they should bolt up and fit with no issues.

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On 9/19/2017 at 1:48 PM, MaybeMe said:

Not much of going back now since I bought them, but I paid $350 shipped a pair of them that have 3 hours on their last service with oil, bushings, and seals. The seller had previously used them on his '04 with no issues.

I figured that rather than spend the money to have the stock forks revalved and sprung, I still might not be happy with them, and everyone praises the SSS and how much better it is, so that would be a step in the right direction.

Not everybody thinks the stock SSS forks are such great forks in stock trim.  I bought at least one new bike every year from 1997 to 2006, sometimes 2 or 3.  Some Hondas, some Yamahas. Some had cartridge forks some twin chambered. The only forks we found to be simply horrible were on a 2006 YZ450. Couldn't race it stock. Even the TC 's on a 99 Honda CR250 were better. All could be fixed by revalving. My favorite forks are 2005 AOSS forks on a YZ250 revalved and with the use of Enzo sub tanks. Bottom line is that no matter what you have or get you'll probably need to modify them. My opinion is you should have typed into this forum before you spent your hard earned money.

 

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30 minutes ago, Budlite said:

Not everybody thinks the stock SSS forks are such great forks in stock trim.  I bought at least one new bike every year from 1997 to 2006, sometimes 2 or 3.  Some Hondas, some Yamahas. Some had cartridge forks some twin chambered. The only forks we found to be simply horrible were on a 2006 YZ450. Couldn't race it stock. Even the TC 's on a 99 Honda CR250 were better. All could be fixed by revalving. My favorite forks are 2005 AOSS forks on a YZ250 revalved and with the use of Enzo sub tanks. Bottom line is that no matter what you have or get you'll probably need to modify them. My opinion is you should have typed into this forum before you spent your hard earned money.

 

I'll see what happens. Worst case is there's no difference. I'm sure I could sell them for what I bought them for and learn along the way.

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I have an 05 with AOSS forks and had my suspension revalved and sprung by George and the crew at ESP (Exceptional Suspension Products, Glendale, CA).

I'm not a good enough rider to notice the difference of anything better than my current set-up.

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The 250f forks are 12mm shorter. I usually like running my foks about 10mm up so you should he ok running them flush. I think you will be happy with them. The only critisism of the SSS forks are they are a bit harsh for off road and trail riding. If you find thay the case lower the oil level and back out the compression. In my opinion they are way bettet than any of the pre 06 forks even stock vs revalved.

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Are you guys sure about the 250f forks being shorter? I think I did measure a pair from 2006 YZ250F to my 2006 YZ125, and came up with the same length. But I might be mistaken? Still they have the same OEM numbers, the inner and other tube and the cartridge? Measure before you ditch them.

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12 hours ago, DrScandinavia said:

Are you guys sure about the 250f forks being shorter? I think I did measure a pair from 2006 YZ250F to my 2006 YZ125, and came up with the same length. But I might be mistaken? Still they have the same OEM numbers, the inner and other tube and the cartridge? Measure before you ditch them.

I don't plan on ditching them. I didn't measure length, but outer tube diameters are the same and they appear to be the same length under load, so I don't see any issues yet. I plan on putting them on this winter when the season is done :) 

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Are you guys sure about the 250f forks being shorter? I think I did measure a pair from 2006 YZ250F to my 2006 YZ125, and came up with the same length. But I might be mistaken? Still they have the same OEM numbers, the inner and other tube and the cartridge? Measure before you ditch them.


Positive. 125/250f are the same length. 250T/450 are longer. Part numbers are the same for almost all the components. I think it is an internal damper measurment that makes them shorter. I have several sets. Next time I have them apart I will measure and see where the difference is.

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7 hours ago, mikedabike said:

 


Positive. 125/250f are the same length. 250T/450 are longer. Part numbers are the same for almost all the components. I think it is an internal damper measurment that makes them shorter. I have several sets. Next time I have them apart I will measure and see where the difference is.

 

That makes senses, thanks.

They look the same length, but that's with the bike on the stand and holding the fork leg next to it.

12mm ain't that much anyways, amirite? :goofy:

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11 minutes ago, MaybeMe said:

That makes senses, thanks.

They look the same length, but that's with the bike on the stand and holding the fork leg next to it.

12mm ain't that much anyways, amirite? :goofy:

Considering it is suggested to adjust fork height in 1-2mm increments, yes. lol

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7 minutes ago, LumberjackLloyd said:

Considering it is suggested to adjust fork height in 1-2mm increments, yes. lol

I kid, I kid haha! 

Either way, I'm sure I can make them work.

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