www.zxrworld.co.uk

I'm not sure that my front suspension is set up right for me and I want to sort it. I've been reading around on here and elsewhere about setting it and, to be honest, I could do with a bit of help as I'm not that sure what to do next.

I've got a White Power booklet which tells you how to work out how much static and rider sag there should be dialled in on preload, but this depends on the total stroke. It is quoted as a percentage. But I'm not sure what the total stroke length is on the L4 forks. So, first question is, does anyone know?

Once I have this it suggests static sag should be 15-30% of total stroke, and rider sag should be 35-50%.

One thing I have measured already is the amount of travel on the front forks between the static position and with me on the bike. This is around 18mm. According to the advice here http://www.gostar-racing.com/informatio ... set-up.htm that sounds about right. So I might be alright with it set how it is.

Another question - is the whole length of the chromed bit of the fork stanchion available for travel? What I mean is, can I assume that the dust seal will travel all the way to the bottom of the chromed part, and the bottom out point is where the chrome ends? Or is there an internal limiter in the fork which stops travel before this point? I've read somewhere that however you set the forks up, once you road test you should have 10mm travel left during normal riding for emergencies without bottoming. So I want to be sure about where I'm measuring this 10mm.

Now to the rebound damping. I find I'm running wide in corners. I'm set up right but as I go through I drift unexpectedly wide. From what I've read I suspect the rebound damping is a bit on the soft side.

My conclusion so far is that the preload is probably about right but the rebound damping needs a tweak.

Any pointers to get me sorted much appreciated.

You cant change the static sag unless you change the springs - if factory these are set for a rider & gear at 125Kgs.

What I done is put a zip tie around stanchion against dust seal and sat on bike - got off and looked at the sag , it's defenetly something like 20mm. I also dialed in the pre-load at zero its for 50Kgs and each segment represents 10~15kgs so I dialed in two - this set the rider sag as is.

SP forks have rising rate at the bottom along with compression at the top. It's a case of dialing these in whats best for you ,choose your favourite road take a screwdriver with you and start making adjustments until it feels on rails.

Ideally you want two fingers worth of stanchion unused to the very bottom, remember the zip tie ? This will now show you what you have left 30~35mm

Hope that helps,

MM!

Thanks MM, I'll give things a tweak and see how I go. You've certainly simplified things there for me

the thing about having a couple of cm space is CRUCIAL! After dropping the forks on a bike, i zip tied up, and checked the clearance between the mudguard and the underneath of the fairing. Even pulling a stoppy, i was just clear, by half a cm. fine i thought. Wrong i was. leaving a petrol station i hit a deep pot hole, about 3 inches deep, at jogging pace, and heard a loud smack as the mudguard connected with the fairing. Imagine if i had been on some b road at 60mph?

Ok guys, I've done it, all set. Here's the story in case it helps anyone else.

Setting the preload on the front wasn't as easy as it sounds. If you put the bike on the stand you don't get the static sag setting as part of the weight of the bike is resting on the stand and the forks unload to an extent. So does the rear suspension. To get static sag you need to hold the bike upright. This caused a lot of confusion at first as I was trying to get MM's 20mm between static and rider sag and no matter which way and by how much I adjusted preload I couldn't get that much. I'm guessing that MM measured the difference between the static sag with the bike on the sidestand and rider sag? You can get 20mm+ with that but not between true static sag (not resting on stand) and rider sag.

So I went back to the websites and they were advising 10-18mm between (true) static and rider sag, which I could get.

Now we go back a bit. Dunno if you remember (or am I too old? ) but when the ZXR 400 came out in the UK it got quite a bashing in the press for the rear suspension being too hard out of the factory. When I bought mine in '94 it almost crippled me back while I was doing the 500 mile run-in, so when I took it back for the service I told the mechanics to get some of the preload off. They did and it was loads better. I've never measured what sag they put on it but as part of today's exercise I did and found I was getting 20mm between static and rider sag. The general concensus on-line seems to be that 20-30mm is the range you're looking for, so I guess I'm on the money with a bit of leeway for when I'm carrying a rucksac, tailpack etc.. But I was concerned that when I sat on the bike it seemed to squat on the rear and not go down even at the front too. So........

What with the difficulties at the front end I thought bugger it, the back is about right so lets go back to factory settings at the front and work from there. Luckily I have the owners manual which gives the settings for a 68kg rider all togged up (bit confused by MM's 125kg, not what it says in my book ). I'm 71kg with my gear on so reckoned what suited Mr Kwak's test rider should suit me just about. The factory setting is preload set with 5 rings visible, rebound damping 7 clicks out from fully clicked in. I dunno why (it was years ago, go easy on me ) but I had fiddled with suspension settings before and they were well off standard. I had the preload increased with only 4 rings showing, and rebound damping only 4 clicks out. So the factory settings were quite a change. So, I dialed the standard back in. When I sat on the bike it was immediately better, sagging evenly at front and rear and not squatting. So, I put a cable tie on the stanchion to measure my 'spare' travel and went out.

Bingo! New bike Mr Kwak certainly knows a thing or two about setting up suspension and I have to say that with a standard weight rider on board the factory settings work. All the handling issues disappeared, it felt much safer, wasn't running wide and I could get right on the gas through corners. And one chap in a car decided to chip in by helping me to gauge the free travel left. On a fast winding road I'm looking to overtake when he decides that the right turn we are almost on top of is a good place to do a U-turn, so slams his anchors on. I get to test the newly installed Hel hoses, the brake bleeding results, the Diablos and the preload settings all in one go - what a helpful guy :wanker Verdict when I get home is that I still have MM's two fingers (is he trying to tell me something with that comparison? ) to play with between the tie and the bottom of the fork.

So, verdict is Mr Kwak knows best about the front if you're about the size of a standard Jap test pilot. Rear preload needs backing off from factory set IMO. You might want to tweak the front a touch either side but if you go too far (guilty ) you'll muck it up.

Be interesting to know what settings others are running. MM sounds to be running standard preload (said 2 rings in from zero, which is the same as 5 rings showing by my reckoning).

so can any one tell me what this would be for a 82kg rider.?? and which way do you adjust to increase/decrease.

I can recommend the DVD by max mccalister at traxxion dynamics @ £30
If u have even a passing interest in suspension this DVD is awesome and explains in no nonsense jargon free plain English(with Americanisms)
Find it via their website or on the bay

Hi guys!
Could you please help me, on which side I can adjsut preload and rebound on the front forks? Could you explain where should I screw to make it harder or softer ( clockwise, counter-clokwise). Sorry for the idiot question but I do not too much about suspension! Thanks for the help!

Above may be one of my favourite ever posts, underneath a complete explanation of setting up the front forks, someone asks how to set up the front forks, absolutely priceless

I can only assume the forum is being invaded by messer abouters.