Boxxer Race 2010 sagging

JBA

I am servicing a Norco DH for one of my son's mates and the bike has a few problems. One is that the forks - Rockshox Boxxer Race - sag about 15 - 20mm under the weight of the bike alone.
Is this a sign that the spring need renewing or can it be down to a lack of oil in the legs?
Judging by the state of the bike generally I suspect the forks have never had a service.

supersonic

Some very sensitive forks will sag under the bike weight - but that is a lot. Is it free sag (as in the spring is not long enough and rattles about if you pull the fork to full extension), or is there resistance?

rockmonkeysc

My 2012 BoXXers don't sag at all under bike weight alone.
The spring could be worn. They don't have infinite life.

JBA

There is a bit of resistance. If I lift the front of the bike off the floor the fork doesn't fully extend. I have to push the wheel downwards to get full extension.
This is the fork 'at rest':



And extended after I have pushed the wheel down:



There isn't any rattle when I fully extend the fork.

rockmonkeysc

Sounds like they need a good service. Could be the seals or bushes are dry and just stopping the fork fully extending.

kickaxe

I had this when I got my new bike out of the box, it needed a whole ride to be normal. I haven't had problems since then...

rockmonkeysc

Rockshox forks all have a lot of stiction from new until the oil gets around the bushes and seals.

JBA

Cheers, chaps.
I'll tell the lad to get the forks serviced (or sell the bike).

rockmonkeysc

Give them a lower lube, should sort them. Half an hour work, just need a lower seal kit and some lube.
The Norco DH is pretty nasty though so sell it anyway.