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15wt and 5wt fork oils

scarbs85scarbs85 Posts: 170
edited February 2013 in MTB workshop & tech
Servicing a set of Tora TK coil forks. Rockshox tech manual tells me to use 15wt fork oil for soaking the foam inserts in the seals, and then squirt some 5wt oil into the lower leg assembly. Ive got a bottle of 15wt which wasn't cheap fornsuch a small amount of oil. Can I just use that in the lower legs, or donI really need to shell out over the top money for a dribble of 5wt too?

Thanks!

Edit// Bit of a thick moment. Misread the oil charts and the 5wt is for the damping in the uppers, it's 15wt for the lowers anyway. So would 15wt be ok for the damping in the uppers!?

Posts

  • bennett_346bennett_346 Posts: 5,029
    Nope. Use the correct weight.
  • bartimaeusbartimaeus Posts: 1,812
    If you use the wrong weight oil in the damper circuit then the damping will be way-off if it works at all... the oil is being pushed through a damping circuit to slow down the movement of the spring, so a more viscous oil will behave very differently.

    In my Toras the volume in the damper is also critical - less than 5ml is the difference between working well and working poorly, so a small syringe is essential to get the oil volume right.

    The oil in the lowers is for lubrication so is not quite so critical - but I's still not use 5 instead of 15 there.
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