Race sag vs static sag problems - help...

**random rider** · 5th September 2010, 17:02

I ride a 2008 KX 125.
I have found that with my short legs I can't touch the ground so have got a modified linkage arm but still couldn't touch ground without doing some yoga moves

Wisely I was told to check out the sag settings. So we have done this and now I can now touch the ground on tip toes with both feet.

This is where I get confused (easily done) - checked what settings are supposed to be and the ranges are;
Race sag - 100-150 Static Sag 30-40

Mine now are Race sag 118 and now Static sag of 62!!!

Also when the bike is on a off ground stand the spring "rattles"

Does this mean that my spring is to "hard" and that I need to replace it or is there something I am not doing???? Why is it rattling???
I am 164cm and 64kg heavy (without gear - so add a few with the gear on I guess/hope)

Any feedback or idea's are totally welcome

**Rupe** · 5th September 2010, 17:34

Originally Posted by random rider

I ride a 2008 KX 125.
I have found that with my short legs I can't touch the ground so have got a modified linkage arm but still couldn't touch ground without doing some yoga moves

Wisely I was told to check out the sag settings. So we have done this and now I can now touch the ground on tip toes with both feet.

This is where I get confused (easily done) - checked what settings are supposed to be and the ranges are;
Race sag - 100-150 Static Sag 30-40

Mine now are Race sag 118 and now Static sag of 62!!!

Also when the bike is on a off ground stand the spring "rattles"

Does this mean that my spring is to "hard" and that I need to replace it or is there something I am not doing???? Why is it rattling???
I am 164cm and 64kg heavy (without gear - so add a few with the gear on I guess/hope)

Any feedback or idea's are totally welcome

Have a look here http://www.proride.co.nz/24001.html

The figure of race sag between 100-150 doesn't sound right to me, check you manual I could be wrong tho.

64kg's you prob could come down one if you really needed, but I'm not sure what effect lowering the bike might have on the spring

**Rupe** · 5th September 2010, 17:37

Originally Posted by Rupe

Have a look here http://www.proride.co.nz/24001.html

The figure of race sag between 100-150 doesn't sound right to me, check you manual I could be wrong tho.

64kg's you prob could come down one if you really needed, but I'm not sure what effect lowering the bike might have on the spring

Just reading again, I think that static sag figure means you spring IS the wrong weight.

**bogan** · 5th September 2010, 17:40

I assume by spring rattling, you mean it is not held captive at both ends, definetely shouldn't happen. Lowering links will affect the effective spring rates in most cases, not sure by how much though. Static and race sag do sound a bit on the high side, but been a while since i done mine.

**scott411** · 5th September 2010, 17:40

race sag is ment to be within 100-115mm, which is where you might be going wrong,

static sag should be more like 30-40mm,

the spring is rattling because you have no preload on it at all,

**random rider** · 5th September 2010, 18:12

Originally Posted by scott411

race sag is ment to be within 100-115mm, which is where you might be going wrong,

static sag should be more like 30-40mm,

the spring is rattling because you have no preload on it at all,

I have the manual but I can't see a definative area that states measurements and I have looked a couple of times for something. Sorry I am a real new kid when it comes to understanding bikes. I can find adjustment range but this states
k= 48 N.mm adjustable range 109-127.5 mm - what does that even mean.

Based on your figures above though I am only 3mm out - if I drop if back to that why is my static sag so far out???

Got my "how to etc" from http://www.teamgreennews.ca/pdf/2005...SettingSag.pdf
Will changing the rebound damping adjustment settings help at all???

**Reckless** · 6th September 2010, 15:02

Originally Posted by random rider

k= 48 N.mm adjustable range 109-127.5 mm - what does that even mean.

Its the manufacturers spring length adjustment range its a guide for making sure your spring has enough travel to do its job. Once your rider sag is set manufacturers have a length you can check measure. In the above case once your rider sag is set if the spring is not between 109 and 127mm they consider you have the wrong spring.

Originally Posted by random rider

Will changing the rebound damping adjustment settings help at all???

No the rebound damping (any damping setting) will not change sag settings at all!

Its going to take some typing to make you understand and I haven't got time at the mo!

One thing to understand is the static sag is very important but only a indicator as to if the spring is correct or not. Its not something you set its something you end up with once rider sag is set. So your not 3mm out, your a portion of the 62mm out, say 30mm.

I'll try and get some more time to explain later ( unless someone else has time to give you a good link or type it all up) Best to have someone come around and explain! Actually thats the best thing or take your bike out to Pro-ride and let Greg have a look if you have wound all the preload off your bike sounds like you might have to buy a new spring from him anyway?

Btw: its bloody good your asking these questions and trying to understand! It is very simple in the end but confusing when you start. Pursue it though, you will love your bike much more with the correct springs in it for your weight.

**bogan** · 6th September 2010, 15:25

reckless summed it up pretty well, heres a link for doing it on sportsbikes, the numbers will be different, but the principals the same. Also, I'm wondering if the modified linkage could cause problems too, the geometry is generally pretty sensitive to small changes.

**warewolf** · 6th September 2010, 21:48

This has been discussed before, a few times. Try searching for "preload" or "sag" either in this forum, or in the "Bike Mechanics: Frame - Suspension - Final Drive" forum.

The site search engine isn't that great, use google instead. You can search all of KB by adding this to your google search:

Code:

site:kiwibiker.co.nz

Briefly:

Your rider sag should be roughly 1/3 of your suspension travel. If the spring is correct, you should have static sag of about 1/10th of your travel. If the spring is too soft, so you've had to wind on lots of preload to get your rider sag, then the static sag will be too small. If the spring is too hard, so you've backed off the preload (which sounds like you've done if the spring is rattling = no preload at all) to get your rider sag, then the static sag will be too big.

**krad_nz** · 6th September 2010, 23:14

When Sacha got her Yamalink it came with some instructions. In the instructions it said what to set the race sag to. The normal values were no long valid due to the change in geometry as a result of the lowering link.

Did you get any similar documentation with your lowering link?

**random rider** · 7th September 2010, 20:49

Originally Posted by krad_nz

When Sacha got her Yamalink it came with some instructions. In the instructions it said what to set the race sag to. The normal values were no long valid due to the change in geometry as a result of the lowering link.

Did you get any similar documentation with your lowering link?

Haha nope - I got it from someone that had it in their daughters bike but took it out when sold it

**random rider** · 7th September 2010, 20:54

Originally Posted by Reckless

Btw: its bloody good your asking these questions and trying to understand! It is very simple in the end but confusing when you start. Pursue it though, you will love your bike much more with the correct springs in it for your weight.

I don't have anyone that will help me out anymore - so decided that this is the best way to find out even if I come across as an idiot! BUT I am slowly learning and understanding my bike.

I know someone that does suspension on bikes but lives over Whakatane way, however they are going to be down at Pumice so will use some girly charm

and see if they can show me as well as explain to me.

Thanks so much to everyone for taking the time to explain this to me. Slowly but surely I will get the hang of this darn thing! Just might be easier when I can touch the ground and don't have to look for a "lump" or "bump" to stop beside!

**Reckless** · 7th September 2010, 23:06

Originally Posted by random rider

I don't have anyone that will help me out anymore!

If you see me out the sandpit or somewhere hit me up I'm happy to chat to a pretty face for hours LOL!!! Your not out East are you? Best shown on your own bike anyway! I'm usually the one that looks like crap and is mumbling about why I put myself through this misery most weekends when I have a perfectly good road bike at home??

Just make sure you tighten up your spring pre-load so it doesn't rattle anymore!! Good luck!