[Closed] How badly affected would my forks be if I used 10wt oil instead of 5wt?

I wouldn't worry about that. There is a difference in the oil, but your unlikely to feel that in the real world.

Thanks!!

Trimix - Member

I wouldn't worry about that. There is a difference in the oil, but your unlikely to feel that in the real world.

I assume you're think of a lower leg service? Changing the damper oil spec is going to make some difference, whether it beyond what can be adjusted out is another matter

Hmm, not sure tbh, I'll be finding out as I go I guess..

I usually up the oil weight in the old open bath Marzocchi's with shim stack damping because I'm heavier than average. It definitely slows them down a little which suits the harder springs I often run.

How much difference it makes to yours depends on the design but it can only increase the damping.

it may depend on the fork. I used the 'wrong' kind of fox oil in my old floats and they would tend to lock up and not get full travel. Changed it for the correct oil and full travel was restored

Rockshox Sid XX, not sure of the year, 2010 maybe..

If for lowers, it's only there for lubrication, so no difference. If for dampers it might make a bit of a difference, but I doubt you'll notice it.

lower leg rockshox is supposed to be 15wt oil. damper oil is 5wt.

10wt will be more viscous so in theory will have heavier damping characteristics. May be fine for rebound as you have the adjustment, but may not be great for compression damping, as it maye impact how freely the fork moves.

I would say significant difference if its in the dampers. Lower leg makes no odds. I put 10w instead of 7.5 in my fork - damping is now set to minimum instead of halfway thru the rnge - beware of forks with only rebound damping adjustment. Compression damping will go up as well

I once put some Hydraulic oil (15w) in some forks and it locked them up solid.

Try watering it down.

I learnt the tough way when I was a teenager trying to reduce reb dampening by putting in 15wt thicker oil on old bombers.
Result being a 8ft to flat chest rib situation.

To say I was a little peeved was understatement.
If I could do it again, I would have bought a firmer spring and topped up with the thinner oil.

As thicker oil will take longer to go through the shims/holes in metal washers type thing so yeah use what is advised to use from your brand of fork.

Keep in mind that I am recalling something I read a while back, that I haven't bothered to research - but I've heard something like that higher wt oils (I think) react more poorly to cold weather - but the oil sticks to the stanchions better and creates a better feeling fork in warmer climates.

The downside being that the UK can get fairly cold.