Advice on suspension set up

[Garry.L]

reckon they are standard Z1000ltd forks,,,,Thanks Paul J

Are the fork springs on the Ltd not different than a normal Z1000?.

[j.wilson]

I think the pictures show pretty standard tyres- is that right?

So I don't think tyres could be the problem.

Nevertheless, I thought I'd mention for completeness:

One thing that can make your special feel strange is that super-sport modern tyres are used (perhaps they came with the wheels).

New bikes have really great lean angles and so the tyre tread has a tighter radius on them so they meet the tyre wall at the steeper lean angle.

This tighter rad makes traditional bikes "teeter" on these tyres.

If you fit wide wheels to your traditional bike make sure you fit tyres that are designed to work on bikes with similar lean angles- as you will get the best shape for your bike and benefit from the stable sticky radial technology.

Consider: wheel dia, wheel width, speed rating, side wall height and shape of the profile- and of course match the front and rear (as the contact point moves from centreline as you lean over and this needs to happen in a matched way between front and rear).

Tyres that are made for "naked" bikes or even the big trailies are ideal- tyres for the Fireblade or the R1 are not an ideal fitment and may even induce more complex problems such as wobble and weave.

[z1bman]

i must admit the rear tyre looks like it has squared of in the middle & the outer 40mm is untouched this will make the bike handle terrible

[j.wilson]

HA!!

[Fred the Zed]

Hi

As discussed above, old and/or worn tyres can dramatically alter a bikes handling. Also check the wheel, headstock and swingarm bearings for any untoward free play. As mentioned above, check the fork oil levels and the suspension movement for bent stanchions or worn bushes. If these are all ok..... then its time to set up your suspension.

The 'sag' settings are one of the most important settings on a bikes suspension. There two elements to sag at each end of the bike. If you completely unload the bikes suspension (eg for the rear, put it on the centre stand) and measure the suspension length either directly or via to fixed point such as the axle centre and a fixed point on the tail piece for the rear, then measure the exact same distance with the bike taking its own weight then you should find that the suspension should compress about 25mm, give or take. Then sit on the bike with your bike kit on and get a friend to measure the same distance between the same points and you should find it has compressed another 15-20mm or so. This is good. Any less and there is either too much preload or the spring rates are too high. The amount of sag should be the same F&R.

On more sophisticated suspension units you will also get compression and rebound damping settings to play with. But this is probably unlikely on an older Zed.

Try that

Fred

[firyembers]

I have been researching suspension setups for some time,since I want to change mine for a fatter tyre and newer usd forks and new style monoshock with piggy back on.

I found a lot of interesting stuff on you tube narrated by Dave Moss,seems he gives track set up tips to road race days,and very informative.

Granted racing is a little different to normal or even fast road,but his style and advice I find very easy to follow.

There are of course numerous books on suspension setups,and I like the free ones...better

There is one called Race Tech's Motorcycle Suspension Bible,which I like and easyish to follow and can also be found for free.

Amazon sell it £15 or so and can be found on eBay.
http://www.amazon.co.uk/Motorcycle-Susp ... 0760331405

I do have it as a 70mb pdf and I can pass it to you or anyone else who sends me an eMail via wetransfer,You can send up to 2gb for free,when I upload it,you get sent a download link.

Hope that helps

[snotie1965]

i dont think you will see many z1000ltd at track days

No you wouldnt,even though it looks like this now!

http://www.z1ownersclub.co.uk/forum/vie ... ht=#251338

Very nice looking LTD !!!! good job done !

[tlc]

I`m totally confused by all of this.
Wasn't Paul's first question about rear shocks being too skittish?
All this talk about sag doesn't apply to a standard Zed surely? If there were any sag on a Z thou that would be all the movement lost in the first place.
Contemporary reports described Thou' rear shocks as 145lb boneshakers.
Yes back then the Japs oversprung and under damped their suspension and things have moved on.
Paul. I bought some cheap shocks that are primarily to allow me to stand up the project bike before I bite the bullet and get some Ohlins. Now on reading this i am very nervous about ordering specific shocks as they will be laid down somewhat.
These guys do some remote reservoir shocks too at £90 which is what I bought as they have adjustable length.
http://tecbikeparts.com/Kawasaki_shock_apps.php

[j.wilson]

"If there were any sag on a Z thou that would be all the movement lost in the first place."

There must be some sag otherwise the suspension would be locked in the fully extended position.

As you go over a bump the suspension should compress from its running position and the bike will rise in reaction. As you leave the bump the suspension should extend beyond its running position- pushing the wheel down onto the ground and maintaining traction.

You need some sag.

Its true to say that too much will cause a problem, but none would be hopeless.

How the suspension/ chassis combination reacts in response to a bump will depend upon spring rates and damping (and loads of other things too).

Obviously if you lean the suspension over more, or change the distance from the pivot point (change the leverage) then the performance will change.

Its not a matter of the performance just getting better or worse- some things may improve whilst other things worsen considerably.

Its always a good idea to set up suspension properly.

Most people will not realise they have a problem with their suspension- in the same way you often see car drivers happily doing the school run with a flat tyre- the first people usually know of it is when someone else mentions it to them.

Poor suspension set up means not keeping the tyres on the ground as much as is possible- this obviously reduces traction.
When you are whizzing around a corner at 60mph the only thing keeping everything stable is two very small contact patches, so make sure you get the most out of them.

Its a hobby, fiddling with suspension is a normal part of it.

[Pigford]

Lets get REAL - it's a Zed - and all the tweaking in the world won't create a "sweet handling" machine

Best to have a bike set up for stable, smooth & comfy

[j.wilson]

Also in the real world it is far easier to upset the handling than it is to improve it.

Why wouldn't you want to get it as good as you can?
Ok, its not going to be brilliant- but there is a big difference between well set up and not set up.

But this stuff is not rocket science, and certainly not beyond the good folks of this forum.

[firyembers]

Agreed JW,i certainly am going to give it my best shot,and putting on new tech suspension with better control over rebound compression and all the rest, am sure will get a vast improvement over how it was 20 odd years ago technology,and considering the wealth of information available to help understand,will make it worthwhile.

I will not likely match the new bike handling,of todays models,but when I rode my zed and scratched hard putting up with twitches,shakes and all the rest,i bet it will be a vast improvement.

My point being,if you want to add usd forks and piggy back shocks,why not learn how to use it...

Sounds a bit like having a dog and barking yerself,

[j.wilson]

Give it your best shot, you can only learn from it.

Of course, I struggle with setting up suspension too.
I'm not trying to be smart arse, I'm just saying ...come on guys, give your suspension some love- and share what you learn.

We could all do with some encouragement to tackle this tricky topic.

[tlc]

We could all do with some encouragement to tackle this tricky topic.

.
Amen to that. It's a bit of a dark art for me at the moment.