How much sag?

Ok, picked up my new to me WRR today. Sweet machine! 179 miles of pavement to get home. She does pretty well on the pavement. I am surely impressed. So now I dive in to the suspention adjustments.

The PO has lowered the bike. It was lowered using a different knuckle instead of the Yamalinks. Is there any advantage to this?? Looks like front is dropped about 3/8 inch in the tripple trees. Not sure I will leave it lowered. It is nice that I can flat foot. But I suspect my sag is too much. I want to get sag correct and tune the suspention first before I consider going back to stock height.

I read in here somewhere that rear sag should be 3.5 inches. Is this correct?

What should sag on front be??? Is there a spacer tube in there that can be trimmed or replaced with longer one to adjust front sag?? On my KLR I just use 1 inch PVC pipe and cut a new spacer.

Thansk!

I set my rear for 3.5 inches and it felt good as far as that went. :)

I am guessing sag in the front should be about 3 inches??

For some reason, you hear and read little-to-nothing about how much the front suspension should sag with your weight in the seat.
I'm sure if you consulted a dirt bike suspension shop/website (or searched for that info on the Internet), you'd get some recommendations.

Anyway, yeah, changing how much the front sags can be done by preloading the spring with different thickness washers and/or with different springs, altogether.
I believe most on here simply set the rear sag, adjust the clickers to suit them, maybe adjust the fork tube height in the triple clamps, and call it a day. :)

Thanks. I guess I will need to have a look at the assembly when I change the fork oil. From the service manual it is tough to tell what size washers might work if I need to decrease the sag. Since there is no spacer in there now, looks like the only way to increase sag is get a softer spring.


Looks like there are tons of threads on fork oil. Looks like the Yami 01 oil is a mystery. Looks like the general consensus is 5 wt oil should work.

I set these bikes up at 85mm to 95mm depending on rider feed back. The fork sag is often over looked, and should be set at around 40mm. To increase preload use a shim on top of the spring. The spring rate is a .47kg good for a 170lbs to 190lbs rider. If you need more sag reduce spring rate. If you need less sag choose correct spring rate and or shim the spring to fine tune rider sag.
5 wt oil is a go. Torco or Maxima fluids recommended. Yamaha fluid viscosity is really a mystery. IMO
oil height set at 110mm

Thanks for the info!

Mr, Go Race wrote:

I set these bikes up at 85mm to 95mm depending on rider feed back. The fork sag is often over looked, and should be set at around 40mm. To increase preload use a shim on top of the spring. The spring rate is a .47kg good for a 170lbs to 190lbs rider. If you need more sag reduce spring rate. If you need less sag choose correct spring rate and or shim the spring to fine tune rider sag.
5 wt oil is a go. Torco or Maxima fluids recommended. Yamaha fluid viscosity is really a mystery. IMO
oil height set at 110mm

Do I understand correctly... If the front end (forks) sit too low (sag), the remedy is to put a 1 to 2 inch shim on top of the spring. Has anyone reading this done that. I'd like to know if I should find an aluminum slug to size? I just can't deal with the front end sitting so low. Specially on hard braking. Almost does a stoppie without wanting too.

Any feedback is well appreciated.

Signed,
The new guy

Mr, Go Race wrote:

5 wt oil is a go. Torco or Maxima fluids recommended. Yamaha fluid viscosity is really a mystery. IMO

So... by the time I stopped riding in November, the front end was so hard it was stupid.

I assumed this was because of the cold and the fork oil.

Assuming I was correct, is a synthetic like Torco the solution to that problem?

Jäger wrote:

So... by the time I stopped riding in November, the front end was so hard it was stupid.

I assumed this was because of the cold and the fork oil.

The temperature has more impact on the space without oil than on the oil itself. Since the space without oil is air and air is gas, then when it's cold the density of the air is higher and the suspension looses some progressive dampening. The rear shock being charged with nitrogen avoids the problem related to temperature. So I don't believe that the oil weight is a big problem temperature wise. Having progressive springs fitted to the weight of the rider is what could more appropriate to take care of the changes related to the temperature.

We can all feel the effect of the temperature when we ride long enough on rough speedy trails. The inside temperature of the fork raises and the suspension becomes mushy. That's why installing releasing some pressure from the front post is a good idea. They sell valves to make the process easier and quicker.

All I've written might be wrong since I'm not a suspension specialist . It's just how I understand suspension works.