yet another springs+oil question :)

[a1fa-]

sorry guys, i searched and searched, and searched and did not find an answer -- probably because this will be rider perference specific, but...

i am 180+ lb. my current suspension settings are set to Rider+luggage per Manual. I just ordered 0.95 springs from Racetech. The calculator showed 0.93, so I rounded to 0.95.

I do not know if I should go with 5W, 10W, 15W fork oil.

< W -- faster rebound?
> W -- slower rebound?


What would you do?

[porsche996]

Slower rebound comes with thicker oil (15W is thicker than 5W). It'll be up to your personal preference as to what to use, though.

I'd go with 10W, see how it rides, and determine if I want to increase or decrease the rebound after that. Means you might changet the fork oil once after the initial install to get it to your likings, instead of twice.

[a1fa-]

Originally Posted by porsche996

Slower rebound comes with thicker oil (15W is thicker than 5W). It'll be up to your personal preference as to what to use, though.

I'd go with 10W, see how it rides, and determine if I want to increase or decrease the rebound after that. Means you might changet the fork oil once after the initial install to get it to your likings, instead of twice.

thats what i was afraid of its trial and error. i thought someone my weight may gone down this road before :0

[pushr0d]

Alfa,

I've been told the racetech spring calculator specifies a spring rate that is frequently a bit stiff for street riders.

That out of the way, just remember that the oil is a damping effort. So the weight of the oil will affect the way the fork responds to "high-frequency" impacts. The thicker the oil, the more the fork will (initially) resist moving, but your perception of it will be a lot like the difference between a fully inflated tire vs. a "soft" tire. Some folks also talk about adding or reducing the amount of oil, to change the air pocket at the top of the fork. Again, HF damping.

The "stock" oil is supposed to be 8wgt. When I changed out the 4 year old oil in my '03, it came out like cold syrup. The 10wgt I put in looked like water in comparison. It made a huge difference.

HTH!

[a1fa-]

i just installed 0.95 kg/mm springs. i was only able to syphen 150cc of fork oil in both forks. i put 175cc of 10W fork oil back in.

my first impressions:
-- slight fork dive is still there.
-- it appears that the bike is holding the line better. i will test this tonight.

[DaveM]

Hi mate,
let us know how you go but I am inclined to agree with pushrod the ride is going to be pretty firm with .95 springs.

I always suggest peolpe that ride on the road try using heavier oil and more volume first then try springs if they feel they need it.

A downside often missed about using heavier front fork springs, is that if they are stiff when riding hard in the corners they will not compress as much and slow down your turn in rate.

With a softer spring as the forks compress in a corner your steering angle becomes steeper and the bike steers more quickly.

It is of course personal preference, I ride pretty hard and have purposefully maintained the softer standard spring for this reason and for ride comfort on the road and I am 220lbs without any gear at all.

Keep us posted with how the result feels.

You may find this website helpful:

http://www.gostar-racing.com/club/mo...4%20all%20abou

DaveM

[a1fa-]

so far so good. i did 60 miles with a pillon. it was awesome. bike holds the line, even with bumps in the corners. i did notice that it is much harder to turn and brake at the same time with 0.95...

I may have went a bit too hard..

HARD: On the other hand if you have too much front compression damping, do not get enough nose dive and the bike will be reluctant to turn and may drift wide on entry to the corner.

...i can quickly over-come these problems by modulating the front brake -- or adjusting the preload. i dont think i have this problem 1up.

[a1fa-]

anyone want to trade 0.90kg/mm racetech springs for 0.95kg/mm :P

[a1fa-]

aww.. you know what pushes my buttons? chipped pre-load adjusters.. no matter what kind of screw driver I use they get chipped.. ***....

[UlsterSpud]

a1fa

I stayed with the original springs but changed the oil. I removed 350ml from each leg and installed 400ml of mixed 10 and 15 weight to hopefully end up with something around 12-13 weight. I measured air space at 113mm. The ride is firmer but she holds a line much better with hardly any dive. B road rides not quite as cushy but A roads almost perfect. Next oil change I will go back to 10 weight but stick with 400ml to see how that works out.