ohlins adjustment

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bulgarianfalco · #16 Post by **bulgarianfalco** » Fri Aug 05, 2011 3:33 pm

whilst I'm inclined to agree damping is probably the issue here, I can't help but feel that preload will affect how hard the ride is too...... I've read some of the interesting threads debating this, but in the olden days we used to adjust the preload of our old twinshocks, ie compress the spring (as that was all there was to adjust) and it certainly felt stiffer and better for a pillion..... or am I completely missing something?

D-Rider · #17 Post by **D-Rider** » Fri Aug 05, 2011 5:34 pm

Yes - I wasn't arguing that firstly the sag needs setting and then the problem is down to damping.
The point I was making is that you set the static sag by adjusting the pre-load ..... so stating that you shouldn't be fiddling with the pre load but should set the sag is somewhat bizzarre as you achieve one by doing the other ..........

bulgarianfalco wrote:whilst I'm inclined to agree damping is probably the issue here, I can't help but feel that preload will affect how hard the ride is too...... I've read some of the interesting threads debating this, but in the olden days we used to adjust the preload of our old twinshocks, ie compress the spring (as that was all there was to adjust) and it certainly felt stiffer and better for a pillion..... or am I completely missing something?

Unless you have variable rate springs, fiddling with the pre'load will not change your spring rate or how hard the ride is. All it will do is pre-load it (hence the name). If you don't set your sag, you'll go over bumps and the suspension will top-out as it recovers.
Stiff damping (particularly compression damping) will give a harsh ride. The rebound damping needs to be set to control the rate of rebound and keep the wheel in contact with the ground.

Nooj · #18 Post by **Nooj** » Fri Aug 05, 2011 7:22 pm

but in the olden days we used to adjust the preload of our old twinshocks, ie compress the spring (as that was all there was to adjust) and it certainly felt stiffer and better for a pillion

With the pre-load wound off the shock will be right at the bottom of it's travel and will 'bottom out' when going over bumps which is probably what was happening with your old twin shocks.

The reason I said stop playing with the pre-load is that if the bike's been set up properly, even for someone else, there will be plenty of travel available, and from the description of your problem, incorrect pre-load isn't a factor.

Unless you've really unwound the pre-load past the minimum mark there will still be enough travel for you to get good damping settings, especially with a heavier weight spring.

bulgarianfalco · #19 Post by **bulgarianfalco** » Thu Jul 19, 2012 7:20 pm

right, it's time to have another go at the rear shock adjustment - currently it's feeling slightly too hard, but bouncing like there's too little damping. Just read the ohlins instructions from the mille manual, but none the wiser.....

I see 2 adjusting wheels on the shock, one at the bottom and one more handily at the top - first which one is which (damping and spring rate) and secondly, any vague suggestions for starting positions?

By the way, the new sportsmarts have helped the feel a lot......

D-Rider · #20 Post by **D-Rider** » Thu Jul 19, 2012 7:37 pm

None of them are spring rate. You change spring rate by changing the spring.

See page 86 and 87 of the Mille Owners manual to see which adjuster does what
http://www.serviceaprilia.com/public/lu ... 202001.zip

bulgarianfalco · #21 Post by **bulgarianfalco** » Thu Jul 19, 2012 8:28 pm

ah yes, I meant how hard the spring felt......so it feels only slightly too hard and crashing over bumps, but wallowing a bit after hitting bumps - to be fair the roads can be pretty ropey here.

I've read the manual - the ring at the bottom is "for the hydraulic braking with extended shock absorber" and the knob at the top is "for the hydraulic braking with compressed shock absorber" - which leaves me none the wiser..... ;)

#22 Post by **mangocrazy** » Thu Jul 19, 2012 8:30 pm

The adjuster at the bottom of the shock is for rebound, the adjuster towards the top (on the piggyback reservoir) is for compression adjustment.

#23 Post by **mangocrazy** » Thu Jul 19, 2012 8:33 pm

What model of Ohlins shock do you have? Is it off a Mille or one of the rare Falco units? I've always found that Ohlins shocks tend to be over-sprung and over-damped on compression, making for a rather 'firm' ride quality. It does all depend on rider weight and whether you regularly take pillions or not, of course.

<Edit> I've just read back through this thread, and the absolute very first thing I would do is to remove the heavy duty spring and put the standard one back on. While you're at it, post up the spring codes that Ohlins stencil on their springs and post them up here.

bulgarianfalco · #24 Post by **bulgarianfalco** » Thu Jul 19, 2012 8:47 pm

cheers for that Mango, I believe the shock is from a Mille, but I'll have a look tomorrow for the spring codes - reluctant to take the bike off the road to swap the springs back for a proper cure after so long immobile thanks to the alarm.......but in the meantime I'll back off the compression v. slightly (anti-clockwise) and try increasing the rebound a little (clockwise, looking from underneath) to attempt to get the silky fluid sensation that Ohlins are supposed to be all about...... ;)

davebms · #25 Post by **davebms** » Thu Jul 19, 2012 8:54 pm

[attempt to get the silky fluid sensation that Ohlins are supposed to be all about...... ;)[/quote]

well yes they are. but as mangocrazy says, if you got to much spring there's naff-all you can do except change it

i have the falco ohlins and the standard spring is spot on for 16 stone

dave

#26 Post by **mangocrazy** » Thu Jul 19, 2012 8:58 pm

No problems... swapping a spring over isn't too difficult a job, as long as you can get the shock off easily in the first place - you'll need an Abba stand or similar to put the bike on, as the back end collapses when you remove the shock otherwise.

Also I'm assuming the shock doesn't have a hydraulic preload adjuster on it - if it does it's more tricky as you will need a specialised spring compressor to get the old spring off and the new one on. If the spring has the usual castellated nuts, then all you need is a C-spanner of the right size.

If you don't have a vice to clamp the shock in, it's probably best to unwind the spring preload with the shock on the bike (suitably supported, of course). Getting the right spring rate on the shock will make a big improvement to ride comfort and handling, especially on dodgy Bulgar roads...

Falcopops · #27 Post by **Falcopops** » Thu Jul 19, 2012 11:10 pm

I'd concur that changing to the softer spring will help.

From your description it seems like it's very harshly damped in compression, but I'm not sure about the rebound.

I'd suggest counting the number of clicks to wind both the compression and rebound adjusters fully in (stiffer), keep a note of these numbers so you can go back to where you started if you need.

Then count the total number of clicks from one end of the range to the other then set them in the middle of the range (half the number of cllicks) on both adjusters.

At least now you will know that you have as much adjustment as you can have in either direction.

Go for a ride and see how it feels.

Then make changes on one adjuster at a time until it feels better. I suggest making changes in increments of 4 clicks. Sounds extreme, but I'd be very surprised if you could feel the difference in a one click setting.

4 clicks should give you a noticeable change to the feel, if it's too much go back by 2 clicks and try again.

Once one adjustment feels better go to the other and adjust in the same fashion, but be aware that changing one will affect the feel of the other. Initally try to concentrate on the feel of the adjustment you are trying to influence until you have a comfortable feeling on the bike.

Then fine tune the feel at both ends.

Falcopops · #28 Post by **Falcopops** » Thu Jul 19, 2012 11:18 pm

I forgot to say that along with the agreement about the softer spring, it's worth trying to see how much sag the hard spring will give you and try to get as close to the correct rider sag as you can.

Preload doesn't affect spring rate, which is a constant, it does affect the amount of suspension travel and as Nooj says it's there to keep the damping part of the suspension in a useable range. Too near the top or bottom of the range can cause topping or bottoming out, where the suspension is nolonger doing anything.

Winding more preload on will also raise your rear ride height, taking it off lowers it, this changes the geometry of the bike and will change how it feels and rides.

So once you change to the correct spring for your weight, you'll need to go through all this again.

Good luck

#29 Post by **mangocrazy** » Fri Jul 20, 2012 6:58 am

I'd agree with all that m' learned fiends have said above, but getting the spring rate right for your weight/riding style should be the first thing you do - everything follows on from that. Twiddling rebound and compression adjusters can never compensate for an overly-fierce spring rate that's trying to kick you out of the seat everywhere...

D-Rider · #30 Post by **D-Rider** » Fri Jul 20, 2012 7:41 am

Yep

1) Spring Rate
2) Sag
3) Adjust Damping