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View Full Version : How much useful adjustment does your bike have with stock shocks?



SPP
4th May 2010, 21:03
The reason I ask is that I don't like how the the front is eager to dive when braking and the front feels too soft. Not plush soft, soft in a bumpy kind of way. I know, crap description. I thought I'd have a noob play and this is what I've noticed:

Sag:
There is no way I can get to 30mm (or just below) sag without winding in the entire preload. I settled on 38mm or 40mm (from memory) which was two turns in from stock.

Damping:
overseas recommended setting had compression and rebound wound almost all the way in (maybe 1/4 to 1/2 turn out). Tried that and bike bounces all over the road. No good for here then.
backed them off to stock and started again. I reckon I have no more than one turn of useful adjustment (from stock). Any more than that and feels like it’s going to let go on bumpy roads. I would even say 1/2 turn more is the most I’d be comfortable adding.
Settled on 1/4 turn more compression and 1/2 turn more rebound. Feels better but 1/4 turn of adjustment only?... really, is that the full extent of adjustment?! Doesn't seem very adjustable to me.

Spring Rate:
Racetech spring calc recommends 0.85-0.90 kg/mm for me on my bike and says stock is 1.0 kg/mm meaning stock is too hard.

Do you think:
the lack of adjustment is down to too hard a spring. Even though there's quite a bit of sag; or
that is the normal range of adjustment and that's just how things are; or
Shaun H recommended removing some oil after some braking tests. Good idea. Haven't done this yet; or
...other

Robert Taylor
4th May 2010, 22:16
The reason I ask is that I don't like how the the front is eager to dive when braking and the front feels too soft. Not plush soft, soft in a bumpy kind of way. I know, crap description. I thought I'd have a noob play and this is what I've noticed:

Sag:
There is no way I can get to 30mm (or just below) sag without winding in the entire preload. I settled on 38mm or 40mm (from memory) which was two turns in from stock.

Damping:
overseas recommended setting had compression and rebound wound almost all the way in (maybe 1/4 to 1/2 turn out). Tried that and bike bounces all over the road. No good for here then.
backed them off to stock and started again. I reckon I have no more than one turn of useful adjustment (from stock). Any more than that and feels like it’s going to let go on bumpy roads. I would even say 1/2 turn more is the most I’d be comfortable adding.
Settled on 1/4 turn more compression and 1/2 turn more rebound. Feels better but 1/4 turn of adjustment only?... really, is that the full extent of adjustment?! Doesn't seem very adjustable to me.

Spring Rate:
Racetech spring calc recommends 0.85-0.90 kg/mm for me on my bike and says stock is 1.0 kg/mm meaning stock is too hard.

Do you think:
the lack of adjustment is down to too hard a spring. Even though there's quite a bit of sag; or
that is the normal range of adjustment and that's just how things are; or
Shaun H recommended removing some oil after some braking tests. Good idea. Haven't done this yet; or
...other


The bike is a CBR600RR? Your height and weight in your everyday clothes?

Like salesmans promises dont believe the marketing hype! ''Fully adjustable suspension'' is one of the biggest and most misleading marketing lies there is. It matters not how much you wind the preload adjuster in or out, if the stock springs are fundamentally the wrong rate for your personal stats then it aint going to work.
Similarly for external clickers, all they are doing is adjusting internal bypass bleed, on compression side its lucky if it makes a 5% difference. If you wind the bleeds out to far it just makes the bike feel sloppy and loose but also doesnt improve the atrociously bad abrupt bump compliance, that because the compression ports are so small they choke off in flow rate and no amount of revalving is going to make those stock pistons work . The external clickers arent going to change the internal shim stacks or ( ideally ) change the piston design and flow rate. Which is what really needs to happen to make these forks work properly on our high proportion of bumpy roads. Plus give you a better response range to adjustment, although its still realistically within 1 to 1.25 turns ideal setting wiondow.
The standard springs need to be ditched for an appropriate linear wind rate for you and at minimum the base valve compression pistons changed to a high flow type so that you dont get that horrible jackhammer feeling everytime you ride over an abrupt bump, which is also unkind to the tyre. With an appropriately arranged valving stack, spring preload and oil level it will also deliver much improved chassis pitch and brake dive control.
Yes it does involve spending money but its far better spent than on say a noisy pipe etc.
PM me for pricing and a menu of options. I can also send you a setupo manual on receipt of your regular e-mail address.

SPP
5th May 2010, 18:44
The bike is a CBR600RR? Your height and weight in your everyday clothes?

Like salesmans promises dont believe the marketing hype! ''Fully adjustable suspension'' is one of the biggest and most misleading marketing lies there is. It matters not how much you wind the preload adjuster in or out, if the stock springs are fundamentally the wrong rate for your personal stats then it aint going to work.

Similarly for external clickers, all they are doing is adjusting internal bypass bleed, on compression side its lucky if it makes a 5% difference. If you wind the bleeds out to far it just makes the bike feel sloppy and loose but also doesnt improve the atrociously bad abrupt bump compliance, that because the compression ports are so small they choke off in flow rate and no amount of revalving is going to make those stock pistons work . The external clickers arent going to change the internal shim stacks or ( ideally ) change the piston design and flow rate. Which is what really needs to happen to make these forks work properly on our high proportion of bumpy roads. Plus give you a better response range to adjustment, although its still realistically within 1 to 1.25 turns ideal setting wiondow.

The standard springs need to be ditched for an appropriate linear wind rate for you and at minimum the base valve compression pistons changed to a high flow type so that you dont get that horrible jackhammer feeling everytime you ride over an abrupt bump, which is also unkind to the tyre. With an appropriately arranged valving stack, spring preload and oil level it will also deliver much improved chassis pitch and brake dive control.

Yes it does involve spending money but its far better spent than on say a noisy pipe etc.
PM me for pricing and a menu of options. I can also send you a setupo manual on receipt of your regular e-mail address.

Yep cheers. 07/08 CBR 600RR

I'll need to weigh myself again. Was 80kg (maybe 85kg) when I set sag but have loss a few kgs (on the rower every morning for the last 6mths to fit into my suit!). I would guess 75kg now.

The narrow window of adjustment surprised me I guess. If that’s normal (for OEM) well... stink. I'll PM you my email.

robboh
25th May 2010, 00:05
I went through a similar exercise with my 06. In the end, after much experimentation (and knashing of teeth) the stock clicker adjustments seemed to be the best compromise to me. The front is particularly horrible with the variable rate springs, and I'm even worse off than you as I weigh 60kgs.

I ended up getting CKT (via Shaun) to revalve / respring both ends. Miles better on smooth roads, nice controlled front end on brakes, clickers that actually make noticeable changes right through the range (and even 1 click to the next). Though I still need to go for a ride down to see Robert as it's not quite right for my liking on Bumpy b-roads.

I see Robert mentioning decent pricing on ohlins shocks at present. Tempting :-)

PS. Also noticeably improved tyre wear and wear behaivour. None of that horrible cupping on the lead edge of the tread. I've done 8.5k on a set of Michelin road 2cts that I put on just after getting the suspension done. Bout 50/50 commuting + weekend rides, plus CSBK and a track day. They have worn uniformly across the tyre, no tread ridging, tearing, or cupping. They are JUST starting to show a slight squaring off in the middle.

Shaun
25th May 2010, 08:07
I went through a similar exercise with my 06. In the end, after much experimentation (and knashing of teeth) the stock clicker adjustments seemed to be the best compromise to me. The front is particularly horrible with the variable rate springs, and I'm even worse off than you as I weigh 60kgs.

I ended up getting CKT (via Shaun) to revalve / respring both ends. Miles better on smooth roads, nice controlled front end on brakes, clickers that actually make noticeable changes right through the range (and even 1 click to the next). Though I still need to go for a ride down to see Robert as it's not quite right for my liking on Bumpy b-roads.

I see Robert mentioning decent pricing on ohlins shocks at present. Tempting :-)

PS. Also noticeably improved tyre wear and wear behaivour. None of that horrible cupping on the lead edge of the tread. I've done 8.5k on a set of Michelin road 2cts that I put on just after getting the suspension done. Bout 50/50 commuting + weekend rides, plus CSBK and a track day. They have worn uniformly across the tyre, no tread ridging, tearing, or cupping. They are JUST starting to show a slight squaring off in the middle.

Very glad you are a happy customer