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Too small to set sag?

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I was wondering if there was a point in suspension set up that a person could be too small to set the bike properly. (Sag specifically). The reason I ask is that I am a 5'5' 145 pound rider of a 2010 yz450. I changed my rear spring (5.7) to a (5.2). While it gave me the ability to get more sag(maybe 90mm max) and smoth out the ride dramatically it still left my static at 60mm just to get to a 90mm ride sag.

thanks

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Those numbers don't sound right for a 5.2kg spring and your weight. You're measuring wrong, have bearing issues or something else is up.

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Those numbers don't sound right for a 5.2kg spring and your weight. You're measuring wrong, have bearing issues or something else is up.

I’m competent in those areas…anything else?

Edited by vet-a-mediate

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Are you sure the person helping you is measuring the sag correctly? How many mm of preload do you have on the spring? Your static sag is way wrong.

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:thumbsup: yep, you were right. I just rechecked and I am at 101mm and 44mm.....so a question?..i replaced the spring a few rides ago. Did I stink at checking the settings in the first place or do the springs break in and settled to my desired numbers.

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:thumbsup: yep, you were right. I just rechecked and I am at 101mm and 44mm.....so a question?..i replaced the spring a few rides ago. Did I stink at checking the settings in the first place or do the springs break in and settled to my desired numbers.

:thumbsup: yep, you were right. I just rechecked and I am at 101mm and 44mm.....so a question?..i replaced the spring a few rides ago. Did I stink at checking the settings in the first place or do the springs break in and settled to my desired numbers.

borderline, too stiff of a rear spring.

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145 pound rider of a 2010 yz450. . rear spring (5.2). . . sag (maybe 90mm max). . static at 60mm [is that ok?]

We have all hear the generic rule that you should have 'x' amount of rider sag, and 'y' amount of static sag for your bike to work properly. For example, you should have 105 mm of rider sag, and 35-40 mm of static sag.

Sounds good, but let's think in extremes (looking at things in extremes is a good way to visualize the possibilities). Say for example you have a YZF 250. The bike weights about 230 lbs. If you take the stock spring (apx 5.4) and give it 8 mm preload, a 170 lb rider might have 105 mm sag with 35 - 40mm static sag (European riders, you will have to accept that us 'Americano's mix meteric and Imperial units').

OK, you have a 170 lb rider with 105 sag and 40 static.

Now you have a 50 lb rider. Eventually you end up with a 3.2 kg spring, for example, so you can get the required 105 rider sag. Take the rider off, and you may have 80+ mm static sag (for example).

Look at the opposite extreme. You have a 500 lb rider. Eventually you end up with a 9.5 kg spring (just guessing for this example) so you get 105 rider sag. What do you think the static sag will be? Probably = zero.

Edited by kevinstillwell

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We have all hear the generic rule that you should have 'x' amount of rider sag, and 'y' amount of static sag for your bike to work properly. For example, you should have 105 mm of rider sag, and 35-40 mm of static sag.

Sounds good, but let's think in extremes (looking at things in extremes is a good way to visualize the possibilities). Say for example you have a YZF 250. The bike weights about 230 lbs. If you take the stock spring (apx 5.4) and give it 8 mm preload, a 170 lb rider might have 105 mm sag with 35 - 40mm static sag (European riders, you will have to accept that us 'Americano's mix meteric and Imperial units').

OK, you have a 170 lb rider with 105 sag and 40 static.

Now you have a 50 lb rider. Eventually you end up with a 3.2 kg spring, for example, so you can get the required 105 rider sag. Take the rider off, and you may have 80+ mm static sag (for example).

Look at the opposite extreme. You have a 500 lb rider. Eventually you end up with a 9.5 kg spring (just guessing for this example) so you get 105 rider sag. What do you think the static sag will be? Probably = zero.

So if I understand you correctly, a riders weight could it make so the bike would not be able to fit a rider within the engineers parameters of where a bike works best?

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