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Basic Suspension set up

Basic suspension set up is pretty much the same for any sportbike with Non Electronic shocks and forks

Here are some basics to think about before we get into the actual settings

The first thing we want to get right are the spring rates. :surprise:

The rates are based on:

Rider weight, seating position, (your height affects this, as well as rearset position), bike use.

Swingarm length (gearing) We like to see a 600 mm swingarm length, measured from the center of the swingarm pivot bolt, to the center of the axle.

Swingarm pivot height.

Front and rear ride height, (not as much as you would think)

Different offset triple clamps, The 2010 and 2011 bikes use a 32 mm offset, the 2012 and newer bikes use a 29.6 mm offset , the best offset for track use, seems to be 27 to 28 mm.

As you lower the offset number, you increase trail, (another worthwhile discussion), the first thing you notice as you change to 27 or 28 mm offset is you can “feel” what the front tire is doing as you initiate a turn, the time between starting to lean in and getting you knee on the ground, it is vague, until you get the offset changed.



The S1000RR/HP4 have a lot of weight on the front forks, this means we use a fairly stiff fork spring

Here is what I recommend:

Front forks, for S1000RR/HP4 all years

We are looking for a RIDER Sag number of 38 to 40 MM, for racing 35 to 38 mm

Once you have adjusted the spring preload to get these numbers, we look at How much preload you have had to use. If the forks have 15 turns of preload adjustability and you have used 3 turned the springs are on the still side for you, or if you have used 13 turns of preload, the springs are on the still side.

Neither is wrong, depending on your use of the bike. For street use a softer spring will deliver a softer ride, with more bike movement. For track use, as the bike will see higher speeds, you may need a stiffer bike with less movement, and a stiffer spring.

Note with Ohlins fork products, forks, and Cartridge kits, you can use different rate springs in each fork, so a 10.0 Nmm in the left and a 9.5 Nmm in the right equals a 9.75 Nmm average.

All weights are Rider weight WITHOUT Gear

All spring rates are in Nmm

As a general rule we tend to go on the stiffer side for track use. The speeds are higher at any racetrack than on the street.

10 N/mm Equals 1.019 Kg/mm or 57.1 Lbs/inch

Front forks

130 to 160 lbs 9.5/9.5 to 9.5/10.0 Nmm

160 to 190 Lbs 10.0/10.0 to 10.0/10.5 Nmm

190 to 220 Lbs 10.5/10.5 to 10.5/11.0 Nmm

220 to 240 lbs 11.0/11.0 to 11.0 /11.5 Nmm

240 to 260 lbs 11.5/11.5 to 11.5/12.0 Nmm

100 N/mm equals 10.19 KG/mm or 571 lbs/inch

Rear shocks

145 to 165 lbs 85 Nmm

165 to 185 Lbs 90 Nmm

185 to 205 Lbs 95Nmm

205 to 225 lbs 100 Nmm

225 to 245 lbs 105 Nmm

245 to 265 lbs 110 Nmm

For the rear RIDER sag we like to see 28 to 30 mm for street use and 25 to 28 for track use.

After the rear Rider sag is set, we use rear Static sag as a check for the spring rate

The rear Static sag should be between 5 to 15 mm

For the front forks

We are looking for a RIDER Sag number of 38 to 40 MM, for racing 35 to 38 mm

What is Rider sag?

Rider sag is the difference between NO rider on the bike, and the front or rear wheel in the air meaning the suspension is FULLY extended and then with the rider on the bike

At the rear the measurement is done at the rear axle going 90 degrees up, I usually tape on a tape measure so it does not move

At the front I measure from the edge of the dust seal in line with the fork tube, to where the fork tube screws into the fork bottom, the fork bottom, is the part the axle goes thru.

What is Static sag?

Static sag is the measurement done using just the weight of the bike, NO RIDER. Measured the same way as rider sag.
 

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What's your take on eccentric washer? (one above rear shock). On 15 RR, I flipped it (opposite of factory default). Bike handles better on turn exits. Do you change it?
 

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Timely information for me as I just got my new Ohlins NIX 30mm cartridge kit and Ohlins TTX MKII shock installed that I bought from Kyle Racing Engines. Planning on setting up the front and rear sag this weekend. Will have to wait until next spring for the next track day to really work on getting the compression and rebound dialed in as the track day season is over up here in the Pacific Northwest.
 

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Make This A Sticky!

A plethora of useful suspension knowledge from a great guy!

Thank you for this post, and thanks for all of your help when I called in for suspension related questions in the past!

Please make a few more offset triples for the 10-11 BMWs!!
 

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It has different springs in left and right cartridge?
Yes, this allows for greater flexibility in tuning. See, Dan Kyle's recommended spring ranges for the front forks listed in the first post.

It works because the forks are physically tied together and operate as a single spring rate as a result.

Similarly, front preload is only on the right and DDC only on the left.
 

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Anyone else out there find the stock springs on a base (non-DDC) 2015/2016 are super stiff? My tuner had to set my compression in front and rear to 1 (rebound 7), and said that was still too stiff! I weight 190lbs with all gear on, but I also removed ~30lbs off bike during its track-only conversion. So far no issues at the track but still getting used to bike and haven't really pushed suspension to its limits.
 

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Anyone else out there find the stock springs on a base (non-DDC) 2015/2016 are super stiff? My tuner had to set my compression in front and rear to 1 (rebound 7), and said that was still too stiff! I weight 190lbs with all gear on, but I also removed ~30lbs off bike during its track-only conversion. So far no issues at the track but still getting used to bike and haven't really pushed suspension to its limits.
I have DDC, so not sure how many clicks are available for non-DDC, but some suggestions:

1. Check preload - spring preload set exactly that - how much the springs are preloaded before any road/track inputs.

2. Put a zip tie on the front fork. This is a very useful tool to understand how much fork travel you are using. You need to know where bottom out is - usually 20-30mm from bottom, but you'll should look that up. If you bottom out (bad!) - add preload. If your zip tie is half way up the fork (This means your front end it too stiff), take out preload first, then tune with compression.

Do you know roughly how much preload is in it? You can measure by count rotations from top to bottom of the adjustment, and remembering how many turns were already set.

I think stock bikes are set with springs for someone around your weight, but again, zip tie will be a really good marker to understand how much of it you are using.

Reading / feeling tire temps are also a good measure of suspension setup. Uneven graining, or odd patterns can tell you alot about what your suspension and tire pressures are. Let me see if I can find a good resources with pictures.

If you take anything from my ramblings, I would at least hope it's the highly accurate zip tie measurement device :)
 

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Reviving an old thread, but seeing that it is a sticky, it would make sense to ask here.

I believe that the standard rear shock length for a 2013 S1000rr is 310 mm. If I upgrade to Ohlins TTX, (Race bike) would you guys suggest keeping the same shock length? If not, what would you suggest the length should be?

Note that the bike is on its lowest setting in the rear?
 

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Reviving an old thread, but seeing that it is a sticky, it would make sense to ask here.

I believe that the standard rear shock length for a 2013 S1000rr is 310 mm. If I upgrade to Ohlins TTX, (Race bike) would you guys suggest keeping the same shock length? If not, what would you suggest the length should be?

Note that the bike is on its lowest setting in the rear?
If you keep the same spring and gearing, and now rear does not squat or anti-squat too much, do not change the shock length/ rear height/ swing arm angle.
If you have now problems with too much squat or anti-squat, then you might consider changing the length of the rear shock.
 
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