rear shock

[littlebigman]

Advice please gang. I need to soften up my rear shock as I weigh next to nothing. After loosening the locking nut I turn the adjuster nut anti clockwise, how far? I want the softest setting, will the adjuster nut go all the way up the thread of the shock? I believe it has 6 settings, what constitutes 1 setting, 1 revolution of the adjuster?
Thanks

[Neosophist]

Advice please gang. I need to soften up my rear shock as I weigh next to nothing. After loosening the locking nut I turn the adjuster nut anti clockwise, how far? I want the softest setting, will the adjuster nut go all the way up the thread of the shock? I believe it has 6 settings, what constitutes 1 setting, 1 revolution of the adjuster?
Thanks

It has 'infinite' settings. It's not a click adjuster shock (only the NC30 K model was like this)

You do NOT wan't the softest setting.

What you want is the correct setting for your weight and intended riding..

There is a formula and way to do this, it isn't too difficult either.

First get a friend to help.

Here is a the quick way that will get it not too far off for general street use.

Firstly get a friend to help you.

Lift the weight completely off the rear wheel (pivot the bike on the side-stand) and measure from the wheel nut, straight up to a point on the rear (use a piece of markign tape so you measure to the same spot.)

Write down this number and do it a few times to make sure you have the same number each time.

Next get in your usual riding gear and helmet and seating position.

Have a friend hold the bike upright and sit in your usual position and bounce the bike a few times.

Have you friend take the same reading and before and subtract the second number from the first number to get your sag.

IE:

Bike fully unloaded (165mm)
Bike with rider (140mm)

This will give you 20mm of overall sag.

You should be aiming for between 30mm -> 40mm for the rear with the rider.

I have 30mm on my rear but I like it quite firm (i'm not heavy)

Rear Preload
Whatever your weight, when you sit on the bike, you want the bike to squat just a little bit (about 30mm) but not too much. You want to ensure that the bulk of your rear suspension travel is available for when you actually ride the bike as opposed to supporting your heavy frame. At the same time you should have a little bit of sag left. If the bike drops too much then increase preload and if you are very light and the bike barely moves under your weight, then soften the preload.

Below is a more detailed explanation. This is easy to set up but can be a bit confusing so just follow the steps one at a time.











Step 1

Step 2

Step 3


Step 1: First find the fully UNLOADED length of your rear suspension. Put your bike on its centre stand. If you do not have a centre stand find a means of lifting the rear wheel up under the engine so that there is no weight (including the weight of the bike) on the rear axle and wheel. Measure the distance between the rear axle and a fixed point directly above like a bolt or mark. Note this measure measurement. Do not use a rear wheel bike stand as there is still the weight of the bike on the swing arm.

Step 2: Find the NORMAL length of you rear suspension. This is amount the suspension drops under the weigh of the bike alone without the rider. Put the bike on level ground and bounce it up and down to free any stickiness. Measure between the same two points as above, i.e. the rear axle and the fixed point directly above.

Step 3: Find the fully LOADED length of your rear suspension. This is the length of the suspension with the rear wheel on level ground and the rider seated on it in his normal riding position in full biking garb. First bounce up and down on the seat to loosen the suspension then get into your normal riding position with all weight on the bike and both feet on the bike. To prevent yourself from falling of (if you have not already) lean the bike against a wall and get your mate to measure between the same two points as above i.e. rear axle and the fixed point directly above.

Next thing is to understand a couple of buzz words. “Static sag” and “Rider sag”.

RIDER SAG is the difference steps 1 and 3. This is the amount the bike drops when your heavy arse sits on the bike.
STATIC SAG is the difference between step 1 and step 2. it is how much the bikes weight acts on the rear suspension or how much you can lift the bike rear without the rider on it before it tops out.





A top racing suspension company suggest that rear wheel rider sag should be around 30-40mm and static sag should be around 5-10mm. However this many vary depending on your bike and manufacturer. The more rider sag you have, the softer the bike suspension will be. I personally use 35mm for road and a few track days use.


Therefore if your rider sag is less than 30 mm then your preload is too hard, if it is more than 40 mm, then it is a bit soft. Once you have set your rider sag as close as possible to 30-40 mm, next check your static sag. If you have more than 10mm then you may need stiffer springs. If however, if your static sag is less than 5mm or you have no static sag then your springs may be too hard for your weight.

If you have to compromise then try to have at least a bit of Static sag in order to stop the bike from topping out.

[oldgreyandslow]

Advice please gang. I need to soften up my rear shock as I weigh next to nothing. After loosening the locking nut I turn the adjuster nut anti clockwise, how far? I want the softest setting, will the adjuster nut go all the way up the thread of the shock? I believe it has 6 settings, what constitutes 1 setting, 1 revolution of the adjuster?
Thanks

It has 'infinite' settings. It's not a click adjuster shock (only the NC30 K model was like this)

You do NOT wan't the softest setting.

What you want is the correct setting for your weight and intended riding..

There is a formula and way to do this, it isn't too difficult either.

First get a friend to help.

Here is a the quick way that will get it not too far off for general street use.

Firstly get a friend to help you.

Lift the weight completely off the rear wheel (pivot the bike on the side-stand) and measure from the wheel nut, straight up to a point on the rear (use a piece of markign tape so you measure to the same spot.)

Write down this number and do it a few times to make sure you have the same number each time.

Next get in your usual riding gear and helmet and seating position.

Have a friend hold the bike upright and sit in your usual position and bounce the bike a few times.

Have you friend take the same reading and before and subtract the second number from the first number to get your sag.

IE:

Bike fully unloaded (165mm)
Bike with rider (140mm)

This will give you 20mm of overall sag.

You should be aiming for between 30mm -> 40mm for the rear with the rider.

I have 30mm on my rear but I like it quite firm (i'm not heavy)

Can you use an abba stand to measure the bike fully unloaded height rather than pivoting it on the side stand?

[Neosophist]

Should imagine so.

AS long as the weight is fully off the rear the shock will extend to it's unloaded length.

http://www.moto-racing.co.uk/Guides/mot ... nSetup.htm

Have a read of this for the full info.

[oldgreyandslow]

Should imagine so.

AS long as the weight is fully off the rear the shock will extend to it's unloaded length.

http://www.moto-racing.co.uk/Guides/mot ... nSetup.htm

Have a read of this for the full info.

Thanks, I thought it probably was, the link in your post is exactly the same as this one http://www.gostar-racing.com/informatio ... set-up.htm I wonder who did the original?

[dogmatic69]

Thanks, I thought it probably was, the link in your post is exactly the same as this one http://www.gostar-racing.com/informatio ... set-up.htm I wonder who did the original?

http://www.copyscape.com/?q=http%3A%2F% ... set-up.htm

Nothing new about that on the internet, people copy stuff all the time.

October 2003 http://web.archive.org/web/200305232343 ... set-up.htm

November 2008 http://web.archive.org/web/200802260905 ... nSetup.htm

This is not gospel truth, but most likely 99.9999% correct given the huge gap. Also, gostar my not even be the original author. Have not checked but they could have copied it.

[Neosophist]

Have a read of the bottom of the link I pasted? It's not just 'ripped off' like many content aggrigators do (i.e. funnyjunk and all that crap)

Same author in the original 2003 article.

Theres nothing fancy about the article but it does break down most common tuning guides into something that can be done over several days.

Once you've got the hang of setting up suspension you can do it in one day, especially at the track. But for the first time it's easier to space it out, too much going on.

Sean Onipede - Click here for Motorcycle Suspension Setup Forum

Big thanks to.
Mike Sladden, (second opinion and accuracy)
Rob Richardson (a few pictures)

(short bio: I am the fastest commuting, speed filtering, street fighting, all year riding, track addict, bullshitting biker out there. Please email me at sean@londongman.com with your comments)

Version 2.1


This document is copyright of Sean Onipede. You may distribute it but please do not delete my copyright information. If you do so I will sue you. If you want to publish this information on your website, please notify me and I will probably agree for a link exchange. This article is for information only.

[littlebigman]

Thanks a lot. I'll get on it.