Honda XR250R Conventional Front Forks vs USD

Anyone able to provide any insights in regards to comparing the conventional front works (as found on a circa 2000) and the upside down (as found on a circa 2004) Honda XR250R?

If one has access to both to select a pair for rebuild, which would be the pick?

According to RaceTech < > the standard suspension specifications for the conventional front forks are:


KYB 41C   41mm conventional
Stock Fork Spring Rate  0.398 kg/mm (stock)  
Recommended Preload  4mm


I'm not sure on details for the USD?


Theres a few kinds of USDs...but a pro company can work wonders to stock forks. Desert handling is what the stockers are good for. More than woods, in my opinion 

On ‎8‎/‎4‎/‎2017 at 6:00 PM, twr7cx said:


Now that is a beautiful bike!!!!

I don't have access to the Non-US spec USD fork specs. The conventional forks are not very good in stock form, and rebuilding them is not much help. The offer no rebound adjustment and are just watered down XR400R forks, shorter, slimmer and same weird valve scheme.

Now, the same Era CR85R youth bike has the USD forks but also the weird valve scheme of the XR's. If the USD on the XR250R in 2004 has this inverted flow shims like the conventionals, they may not be much better but if they offer adjustable rebound I would pick them first.

I must be one of the few people on this planet that actually is OK with the stock forks, I considered replacing or throwing a ton of money at them, but now I won't.  I've owned the bike, an 03, since new and over the past couple years I have managed to set the stockers up to the point where they do fine.  Messing with combinations of what you already have, including front tires and tire pressure, may get you to a manageable place.  One hint, those charts on sites that sell springs that tell you what spring to use, go with one step lighter than what they suggest. ;)

There's nothing inherently better about USD other than they can be stiffer. The early USD were not upgrades over the best conventional forks of the time and when the fork seals leak it immediately pumps/drains ALL the oil out, where a conventional fork seal weeps and you have time you can ride while it's leaking slowly. 

 Not sure what they used for that bike, all the motocross swaps here end up with a much taller front end due to the forks being much longer. 

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