The 5.0N Ohlins forks springs 8716-50 and 8709-50 have been discontinued and are no longer available. Ohlins have, for economic reasons, rationalised their range of fork springs for the XTs.

The only Ohlins springs available for the XTs are the 6.0N 8716-60. They are 593mm long (even though they say 590 on the box!) and when fitted to the X they need no spacer and when fitted to either the R or Z require a 40mm spacer which should have been supplied in the box. You should be fine with what you have been sent.

FYI the OE XTR springs are 633mm long and have no spacer as standard. The XTZ's OE springs are 583mm and have a 50mm spacer fitted as standard, which makes the overall length the same as the R at 633mm. The XTX with its shorter travel front end takes the 593mm spring with no spacer either with OE or the Ohlins springs.

Hope that helps. I'd guess (?) OTR have springs that are old stock from the days when three versions were available and just happen to be labelled XT660X. Bit naughty as they should have either told you, or amended the sticker on the box so you knew what was going on.

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