Rear suspension - general question.

After Luke (Denz0 on here) refurbed my RT's original rear shock, and fitted a new spring, I've been very pleased with the improvement. But......for reasons unknown ......I fiddled with the settings, to the point where it felt horrible, and I'd not made a note of the starting point! All's good now though - it helped when I realised that tiny adjustments of the damping screw made big differences, I'd been doing a 1/4 of a turn at a time, whereas just 1mm of movement had a noticeable effect.

Anyway, in the handbook, we're told that, if the preload is increased, we must also increase the damping. If my understanding of preload is right (and it may not be, of course) it just makes the bike sit higher or lower. If that's all it does, why does the damping need to be changed at the same time?

Pete

Great question. I'll have a go at answering but this is just my view as I am no expert.

Damping changes the speed at which shock can compress/extend for a given weight.

If you add weight to the bike, say a 60kg passenger, you have to add preload to offset the extent to which the back of the bike falls with the additional weight.

However, as you now have more weight acting on the shock, the speed at which the shock can compress/extend will also change. More weight = more force pushing oil through internal shock valving, so faster flow of oil and faster compression of shock. To offset this you need to increase compression damping to get to same rate of change as prior to adding weight.

The wrinkle is that I don't think you need to adjust damping if you are simply setting ride height of bike. Lets say, for example, that you want to raise the rear slightly but your weight is unchanged. In that case you can leave damping alone.

In terms of set up, normally turn adjuster all the way in, record the total number of turns of adjuster, then record the extent to which you back it out. For the first adjustment, record the number of turns from stock position to fully in so you can get back to original setting.

Good answer, thanks, I understand that.

Pete

NicD answer by nico,

only bit I'd add, like a carb screw.... never wind the screw in hard, you want the lightest of touches to bottom the screw

All good advice,
However, if the spring is wrong,you cannot adjust it away.
IF your happy the spring is correct,
Back the damping away till the bike starts to misbehave then bring it back up to a point where you like the ride,.
Bit easy if you only have one adjustment on the lower shock body,bit more if you have high speed,low speed etc etc

mikeyboy said:

All good advice,
However, if the spring is wrong,you cannot adjust it away.
IF your happy the spring is correct,
Back the damping away till the bike starts to misbehave then bring it back up to a point where you like the ride,.
Bit easy if you only have one adjustment on the lower shock body,bit more if you have high speed,low speed etc etc

Click to expand...

Cheers Mike.

That's the method I used to get back to something nice - it surprised me just how much a very small turn of the screw affected the feel.

Pete