XJ900 forks

Just got back from 2 days away with work, went to move the bike and theirs a pool of oil under the front wheel. The forks have been leaking while i was away. I have always run 22Psi in the front (high i know) for it to feel ok, (getting up to 28months now) with out a problem. When i let the air out the forks sag ALL the way down to the bottom, shouldn't they still sit up on the springs alone? I'm getting the idea i really need new fork springs desparately. Where should the forks sit normally with me on the bike? Midway, 3/4's way up, almost to the top?

 

Rule of thumb for all bikes is 25-30mm sag when you sit on the bike.

Where has the oil leaked from? The seals or the damper bolt?

 

Out of the top of the bottom leg seal, dripped down on to the calipers (missed the pads and discs) onto the rim and around the side wall and collected under the tyre. If i hadn't moved the bike i would have got on ridden off and not noticed--- until i used the front brake or turned! It just seems odd for the front end to drop completely without air, i would have thought that even with tired springs it still would have sat up a bit. If you let the air out of yours (assuming you have air) where does it sit?

 

With mine ..without air sitting on th sidestand it looks th same as with air
Sitting on it with air it's about what Hillsy said, without it,s a little lower. I have original springs. p.s got down to 5.4L/ 100K th other day on a 360K run.

 

22 psi?
Max = 17.
. . . . . . . . . .

The Stock Front Fork Springs they put in the 900 weren't up to the job.
Even on top maintained 900's with working Anti-dives and 12 psi. in the Tubes ... the thing kneeled-down going into a tight turn so bad that the Work Stand would scrape.

I set-up the Front-end on mine with a few layers of Tin Foil shimming-out the Slider.
Progressive Suspension Front Fork Springs.
3.75 cm's of Fork Spring Pre-Load.
295 ccm Permatex Hydraulic Jack Fluid (+9 ccm's over)
Zero - psi.

Not if there was only something to be done about the Faring.

(Attn: UK - AU 900 Owners. Wanted: Belly Pan for 900)

 

So the bottom line is they are either the wrong springs or they are definately dead!

 

Finished on call so back on the bike except it's lost nearly all its air and pumps fluid out as the forks compress each time, so it's home to the shed and park it! Now riding a ZZR600 Kawasaki (55,000Km's), not as comfortable as the XJ (bit like a praying mantis riding a flea) but jeez the bugger flys when it's on the boil! Also had to deliver a GTR1000 from the bike shop to a mates (the ZZR's owner), nice to ride (boy my suspension is stuffed) but the XJ would eat it for grunt. Anybody used Ikon springs? They list them for the XJ.

 

That's 43.45 MPG

I could use new springs too- - your's are shot

 

That's 51 MPG over here................
Sorry for th messing with your thread.. knuts2a.

 

But now you're using Imperial gallons (I think)

http://en.wikipedia.org/wiki/Miles_per_ ... n_from_MPG

 

I stick to lt/100km's at least it's easy to work out. (did grow up with MPG).
Well the bikes up on stands and i have dismantled one fork. plenty of gunk under the top dust seal, also looks like a bit of pitting on the slider. Measured the spring again it is 532mm, the book says 522mm. At 522mm the top cap would screw on with my fingers, even the current springs take little effort to screw the cap on. From memory with bikes years ago, you had to lean on the top cap with a bit of weight against the spring to get it started and done up. These ones have been easy. 522mm would have no tension. Any thoughts anyone???

 

Contacted IKON springs today, their springs are 525mm in length, still shorter than my current. have to measure and count the coils on my current springs and they will work out the spec's and compare with theirs. Also on the damper rod it shows 2 "springs" above the "taper spindle", i can't find these, unless they are the bits still in the end of the inner tube.

 

knuts2a..whats th price for th Ikon progressive springs ..to your door that is?

TIME..yes Imperial..thats what we were b4 going metric.

 

Ok, so it's a 600 not a 900 but my springs protrude above the top of the fork slider by 1 inch/25mm when you remove the cap. To refit the cap, I have to apply firm pressure to compress the spring so the cap will engage onto the thread. No anti-dive on the 600 though.

 

knuts2a..whats th price for th Ikon progressive springs ..to your door that is?

$169 inc, delivered.

 

Thought I'd chip in with spring prices.
I recently replaced my springs with an aftermarket Progressive Suspension model from Chacal and delivered to my door within 5 working days they were $US112.

My bike has a XJ900 front end but without the air assist when I removed my old springs they were way out of wack - 517.5mm by the book but mine measured at 542mm and I suspect they were the original springs and very very tired. The replacement springs were 521mm long and have been great, I even have rebound now

 

Ok, thats interesting, so they measure longer than than specified. I wonder if as they lose their "springyness" they stretch?
Any engineering types got a comment.?
I gave all the details of my current springs to IKON and they is working out what they would have been compared to original spec.
Still checking prices, i will probably be doing an order to Chacal as i need internal bits for the forks anyway.

 

Finally got the second fork leg to bits, made up the special fork tool, a spark plug spanner, drilled thru and filed out so an extension bar fitted in the wrong end. Conclusion is they've been to bits before. The three wavy washers i couldn't find on the first leg where in the right place, above the tapered spindle, but it was missing the copper washer on the damper rod holding bolt. Went back to the first leg for a closer look and found the missing washers, jammed at the bottom of the tube, the only way to get there was to have been assembled wrong. Managed to fish them out with a long bit of wire but one was broken. At last i can do a parts order now i know what's going on.
Also spent the afternoon on the GTR getting it ready for another trip to Adelaide (450Km), including changing the stock pipes back over to some Pipeline pipes. The owner said it runs a "bit" nicer with them on, sounds nice, just hope the locusts have settled down a bit by then, (and the cops have their ear muffs on).

 

New Progressive springs and seals from Chacal in and fitted, fork 5 oil, 160mm from the top (~300cc's) bike sits up now with no air! Still a bit too stiff at this stage have only ridden in to town and back in the rain (30K's), but might need to let out a bit of oil. Now i can really feel how bad the rear shocks are!