Suspension Questions (understanding)

[Fowlersrs]

Right I feel quite noobish in the fact ive had bikes for a while but never really considered how much adjustability there is with motorcycle suspension with just using tools compared to what there is with cars, its something ive never considered looking at, prob a bit scared too if im completely honest!!

But in order to rediscover my little speed four ive decided to start having a play, im bless with having all 3 adjustments front and rear so im well and truly jumping in at the deep end. Im gonna have a whole load of questions on the way and im hoping a few peeps can help explain exactly what effect the things im adjusting have on the bike and how it rides.. thats whats important for me, understanding why im doing these things..

so ive had a good read of articles supplied to me about the 3 settings, preload, damp compression & damp rebound. the way I see it is that the most important thing to setup first is the PRELOAD.

so here is my first question;

setting the preload in general is based on rider weight correct? In particular on the rear it is necessary to do this because your weight is directly over the rear shock?

Now Performance bike mag did an article on my speedy four settings a while ago and based on a rider weight of 170 pounds, incidently bang on what I weigh they have come up with the following settings for pre load;

PB Road settings:
rear-
preload: 44mm threads showing above lock ring
rebound: 0.75 turns out from full in
compression: 0.5 turns out from full in

front-
preload: 3 lines showing
rebound: 0.5 turns out from full in
compression: 0.5 turns out from full in
tire pressure: 36 ft, 42 rr

Now for a moment its rear pre load I want to focus on as this is the only thing im struggling to adjust because the frickin nuts are so tight? As standard the speed for has 37mm thread showing above the rings, now theyre suggesting adjusting this down to achieve 44mm above the lock rings..

my question is what does this actually do to the bike, the way it looks is im winding the lock nuts down onto the spring and putting the spring under more tension? so this could be why its so hard to budge? Does this then lower the bike, if u weigh less u can have the bike lower to the ground? and does this then make the back end more stiff as a result?

[MarJay]

[Fowlersrs]

Right so let me get this straight, winding the locking nuts down and compressing the springs (hence showing more thread above) is defined as increasing the pre load correct?

Does this have the affect of increasing the ride height or lowering it?

To me it sounds like it would lower the bike and increase static sag as with more compression on the spring the bike will sag easier?

What I'm trying to work out in my head is why are the winding down to achieve more/less preload from the standard setting of 37mm above the lock rings to 47mm, what are they achieving by doing this to the bike?!

[mentalboy]

I found this an interesting read.

https://www.gostar-racing.com/club/motorcycle_suspension_set-up.htm
____________________
Make mine a Corona.

[Fowlersrs]

[weasley]

Just to get over a common myth. Increasing preload does NOT affect spring tension. All it does is raise the height at which the spring settles to its loaded rest point. It is to alter which part of the shock/fork's travel is used (to prevent bottoming out but allow as much stroke to be used as possible).

You can not affect a spring's tension by twiddling a nut.
____________________
Yamaha XJ600 | Yamaha YZF600R Thundercat | KTM 990 SMT | BMW F900XR TE

[Fowlersrs]

[Fizzer Thou]

Making the spring less in height increases preload on the spring.This increases the rear ride height and decreases rider SAG.

The damper clickers do not affect sag.Get the SAG correct first then adjust the clickers 3 steps at a time so that you can feel a change.One click here or there you will not notice.Keep a note of your standard settings so that if you get into a muddle you can always resort back to where your last preferred settings were.

I found that when I bought my R1 the first time out on it the ride was all over the place on standard settings - which was probably the reason why my friend sold it to me.I then adjusted it to some recommended settings and it was far better.But after I changed the shock and fork springs to Ohlins items I had to go back and set it up again,starting with the SAG.But it does make a big differance to the quality of the ride - much more fun
____________________
Just talk bikes.What else is there?

Always have a 'Plan B'

[MarJay]

[Fowlersrs]

[MarJay]

[Fowlersrs]