Originally Posted by Cotten Mouth Chris
so im 165 with my gear on i have an 02 919 should i be riding the rear shock as soft as it will go with that little notch thing on top of the spring? how did you like the new shock was it worth it and how much was it?
my shock is built but Ohlins spring is on backorder and we still have snow on the ground, so no testing for me yet. You are asking about preload. It all depends on what numbers you are getting for the sag.
Here is what you need to do,
#1 - find someone to help you
front rider sag:
lift up you bike by the triple ( hang it by the frame from garage roof rafters etc) so your front wheel is hanging free in the air with forks fully extended. Measure (use mm) from the axle to some point on the lower triple. Call this measurement L1
sit on the bike in full gear in your usual riding position with your feet slightly touching the ground as not to transfer your weight to your feet but just keep you bike from falling. Ask your helper to gently lift up your handlebars and slowly let them settle. Measure again at the same spot as before, call it L2
Have him gently push down on the front of the bike, and let it slowly rise up. Measure once more for L3
Sag = L1 – (L2 + L3)/2
Magic numbers here are 30-35mm for the street
If your measurements fall out of range, adjust your preload: stiffer (clockwise) for less sag, softer (counter-clockwise) for more sag. If you have no fork preload adjustability (02-03 919) you can take your for cap off and use lots of washers between the spacer and a retainer washer until you get right numbers. Than cut your spring spacer to the lengh of your existing spacer + washers you used (PITA method)
front free sag:
•Take the measurements the same as for rider sag, but measure L2 and L3 with no rider on the bike. Should be around 15-20mm
rear rider sag:
Measure the distance from the axle directly up to a solid point on your bike’s subframe or bodywork. Call this measurement L1
Sit on the bike in full gear, in your usual riding position.
Ask your friend gently lift up the rear of the bike and lets it slowly settle on its suspension. Measure again. Call this measurement L2
Gently push down on the rear of the bike, and let it slowly rise up. Measure once more for L3
Sag = L1 – (L2 + L3)/2
Rear sag should be 30-35mm
for street riding
If L3-L2 is more than 25mm for the front end, or more than 5mm for the rear end, there is too much friction. Investigate.
If your measurement fall out of range, adjust your preload: stiffer for less sag, softer for more sag.
rear free sag is measured the same as rider sag just without rider: 5-10mm is the number here
To recap the above:
SPRING RATE - Spring Rate OK - Both free and rider sag within acceptable range. Spring Rate too soft - Rider Sag OK, but too little or no Free Sag Spring Rate too firm - Rider Sag OK, but too much Free Sag
SAG - Front - Rider Sag - 30-35mm (25-30% of Full Travel) Free Sag - 15-20mm (60-70% of Rider Sag) Rear - Rider Sag - 20-30mm (race), 30-35mm (street) (25-30% of Full Travel) Free Sag - 5-10mm (extremely light bikes use less) (15-25% of Rider Sag)
Just to give you an idea, the procces should look kind of like this:
YouTube - Honda 2008 CBR1000RR Stock Suspension Evaluation