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How to set sag for front forks?

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OK, I have checked around some to find out how to adjust the sag in the front forks.

I ride an '02 WR 250f.

I have resprung the bike(front and rear) for my weight.

The sag checks out just fine in the rear.

However, the front doesn't seem to have any free sag at all.

How is this ajustment made?

Less fork oil?

Spacers?

Please help.

:)

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OK, I have checked around some to find out how to adjust the sag in the front forks.

I ride an '02 WR 250f.

I have resprung the bike(front and rear) for my weight.

The sag checks out just fine in the rear.

However, the front doesn't seem to have any free sag at all.

How is this ajustment made?

Less fork oil?

Spacers?

Please help.

:worthy:

This is a re post of mine and I did look on the Race Tech site without any results.

I need to redo my fork seals and would like to try and set free sag. Right now I have zero free sag.

Is there too many washer spacers and or oil?

What are your opinions?

All help is appreciated.:D

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However, the front doesn't seem to have any free sag at all.

the bike was on a stand, then you released the stand and the fork doesnt move? or how did you measure the sag?

I never measure the sag of a fork because friction plays a major role there

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Yes, I set the bike on a stand, took a measurement. Then I set the bike on the ground, pumped it and took another measurement. I did not sit on the bike while measuring.

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Yes, I set the bike on a stand, took a measurement. Then I set the bike on the ground, pumped it and took another measurement. I did not sit on the bike while measuring.

the result depends on the release point. compress the fork with engaged brake lever and release it slowly. then you should have some sag - if not something is wrong.

usually oil level has nothing to do with fork sag.

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I see this a lot. There is NO sag measurement for forks. The correct spring rate for your weight is what you need. Oil level has nothing to do with ride hieght. Some people like thier springs to have some preload, they use washers. I dont llike preloaded springs myself and neither do most suspension shops.

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Just for the info.

My forks have 40mm freesag, with 0.38kg/mm springs, no pre-load whatsoever. 65kgs rider.

My ride height is 75mm.

The springs have a lot to do with the freesag, as you can imagine.

Someone who runs 0.46kg/mm springs can never get the same freesag as i do.

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Just for the info.

My forks have 40mm freesag, with 0.38kg/mm springs, no pre-load whatsoever. 65kgs rider.

My ride height is 75mm.

The springs have a lot to do with the freesag, as you can imagine.

Someone who runs 0.46kg/mm springs can never get the same freesag as i do.

ok, lets do some math. I take simple values so the results isn't 100% correct but we can see how much difference we can expect...

a bike with 100kg puts - for the sake of convenience - 50 kg on the front wheel, thats 50kg / (0.38 x 2) = 66mm of sag with 0.38 springs / no preload (the angle is not 90°, thats why we have less than 66mm free sag).

with 0.46 springs we have 50kg / (0.46 x 2) = 54mm, thats 18% less.

100 points for netherlands :D

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I see this a lot. There is NO sag measurement for forks. The correct spring rate for your weight is what you need. Oil level has nothing to do with ride hieght. Some people like thier springs to have some preload, they use washers. I dont llike preloaded springs myself and neither do most suspension shops.

So will pre loading decrease the free sag?

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So will pre loading decrease the free sag?

yes, but spending 2 seconds on fork sag is a waste. have you ever seen or read any article regarding fork sag? Sping it to your weight and you are done. Fork sag is a result, not a starting point. You dont spring a fork based on sag, you do it based on your weight. whatever the sag happens to be is what it is, doesnt matter.

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Given that sag measurements are necessary on the rear, doesn't it stand to reason that sag measurement would likewise be necessary for the front?!

'You don't spring a fork based on sag'..........Why not?

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Hmmm, hadn't thought about this in a while. Back in the day we used to pre load forks with cut pvc pieces above the spring, I think everybody quit doing that around 87 when cartridge forks came out. I was on minis back then so I can't remember exactly how we did it or what the formula was. Could have sworn though that Ohlins forks had a preload adjustment on them not long ago. Anybody ??????????????

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So will pre loading decrease the free sag?

Yes. Ordinarily an increase in preload will be accompanied by a corresponding decrease in free sag.

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There is an adjustment for fork spring preload on many of the newer KTM's, and of course preload is adjustable on any fork by adding or removing teflon preload spacers.

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look in your manuaL. You will find a section on how to adjust your rear sag, nothing on the front cause in terms of adjustment ther is no such thing.

In my owners manual, section 7-15 it shows a diagram and says' The spring pre load is adjusted by installing the adjustment washer between the fork spring and damper rod.' This is for an '0 WR250

I still feel that I need to check;

1. proper spring length

2. If the length is correct, find and remove pre load washers.

What do you guys think?

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In my owners manual, section 7-15 it shows a diagram and says' The spring pre load is adjusted by installing the adjustment washer between the fork spring and damper rod.' This is for an '0 WR250

I still feel that I need to check;

1. proper spring length

2. If the length is correct, find and remove pre load washers.

What do you guys think?

correct, but that is preload adjustment, not sag adjustment. If you ride single track or trail ride, I would not want to preload the springs as they can have a tendency to deflect off rocks or roots for example. If you want to maintain a plush feel, no preload. If you are charging through the desert hitting whoops then maybe you will want to add some preload to hold the front end up, it also will make the bike more stable.

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