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Suspensio has been Wrong

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I took my bike for service and wanted to set my suspension right. Make a long story short. when he had me stand on the bike to measure the compression of the back spring to the fender he said that I was 45 mm off. It should be at 100 and its at 55 mm. ( I could be saying it wrong) the bottom line is should I have the mechanic put it to 100mm. What changes will is experience. He said it was too stiff right now and that it would become softer. Honestly I am used to it the way it is. I'll change it if makes me a better rider or enjoy the ride. Apreciate your opinions and advice.

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You didn't mention what bike this was for. The "sag" should be around 1/3 of the rear wheel travel as a guide line.

You don't need a mechanic to change that. Do it yourself and give it a try!

Getting the suspension dialed in for your weight, riding style, and terrain is the best thing you can do.

Ride on

Brewster

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I bought a bike used wr450 last year from a guy who said he had it setup for his weight. He looked about 30-40lbs heavier than me, but whats a few lbs between friends, right?

WRONG!!!!!!

I have had several quite spectacular crashes and broken bones while riding the bike. But, it was my first real dirtbike in 20 yrs and I just had no idea what a good ride felt like. So I just adjusted my riding to the bike. The front end felt very heavy and it made it hard to turn, especially at speed. The rear wheel was spinning all over the place and I was landing very hard and wrong off of simple 4 to 5 foot drop offs.

Last week, I put the correct springs on and set my sag to about 100mm. It was at 68mm previously.

Now, my simple test rides clearly show that the bike feels lighter and more balanced. My body position now seems to have a much bigger impact on turning. Also, the front wheel comes up very easily now.

I can now practice the "when in doubt, gas it" and "keep the front end light" techniques. I have to get familiar with the bike all over again.

Its going to make a big difference and you will like it. Also, learn how to set your own sag. You don't need someone to help you with that. It takes about 15 minutes.

So go ahead and do it!

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Forgot to mention my bike, its a yz250f 2002. I posted the original post. I'm putting it back to 100mm and see how it rides. thanks for the advice and what to expect, sounds like I will have a brand new feel to the bike.

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David setting the sag on a bike is as easy as chewing gum and walking at the same time.

Start by puting the bike on a stand and measure from some place on the swing arm (I use the axel bolt) and the fender or number plate. Mark with a pen the place you are using on the plate or fender so you can use the same spot for the next few measurements.

Note the measurement.

Next put the bike on the ground. The bike will settle on the suspension some. Do the measurement again. This is the static sag. Push the bike down so the suspension compresses, let it return to the resting position again and take the measurement again. Take the ststic sag measurement again. I take the static sag measurement several times so I can tell if the measurement is accurate. If the measurement is a couple of mm off, no big deal. If the measurements are 5 or so mm off the linkage is binding.

Now that you know the measurement of the suspension at full extension and the static sag get on the bike in the attack position and bounce some. Let the bike settle and measure from your fixed points again. This is rider sag.Do this measurement a few times so you know that it is accurare and note the number.

The static sag should be aroung 30 to 35 mm. This will tell you if the preload on the spring is correct. If you come up with 20 or so you have too much preload on the spring. If you come up with 40 or so mm you dont have enough preload.

The rider sag is the total distance the bike drops from the measurement you took with the bike on the stand and with you sitting or standing on the bike. You should come up with around 100mm. If you do not have around 100mm turn the preload nuts so you come up with 100mm of rider sag. Now that you have the rider sag at or near 100mm the static should be in the 30mm range. If you dont have around 30mm of static sag you need a different spring rate. 20mm of static sag you need a stiffer spring and 40mm of static sag you need a softer spring. :thumbsup: Clear as mud?

Kevin

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