OzVMX Forum
Marque Remarks => Kawasaki => Topic started by: piney on April 26, 2012, 09:11:46 pm
-
i have read on other threads, re 89kx250 Us spec is a better bike than the Aus spec bike, can someone please explain th difference. I have a mate who can export bikes and is keen on a pre 90 bike . he,s a fan of the fried chincken wing but i think i can convert him ;D ;D
-
The main difference is the front forks. Aus got the first modle Upside down's ,US got 46 mm conventionals up from the usual 43 's . The US forks are better.
-
Also the rear wheel
US has 19" rim
Aust. has 18" rim
This and the forks are the only difference that I know of.
-
thanx for clearin that up
i have an aus spec 89 (great bike) i think !!
might have to try fnd a set U/S spec forx
-
hope i,ve done this right here it is http://http://www.youtube.com/watch?v=jRK2nDMtg-A
-
The main difference is the front forks. Aus got the first modle Upside down's ,US got 46 mm conventionals up from the usual 43 's . The US forks are better.
There not just better! There a shit load better ;)
-
have a friend with an Aus 89 Kx 250. The forks are a bit average. Can they be inproved with gold valves,springs etc or does the problem go deeper than that. Im also guessing the US forks are hard to come by.
-
My 89 RMX has similar forks (41mm USD KYBs) but mine are the full cartridge model. From what I'm told the problem with them is due to the design causing stiction making them feel harsh early in the stroke, mine are a little harsh but it's not excessive, maybe cause I'm running .46 springs with bugger all preload?
46mm conventionals would be the go but they under hang the front axel big time, not good if you trail ride.
-
USDs flex mostly at the top of the lower tube. When that (momentarily) bent tube tries to move through the bushes, it binds up.
RWU forks flex mostly just below the lower triple clamp - well away from any bushes. Even though there's more flex, it's doesn't cause binding.
The second year of Japanese USDs deliberately reduced the stiffness of the upper leg to minimise the problem, but all of the 40 and 41mm USDs are pretty crap because of it.
USDs only really began to work properly when they got to 46mm.
That said, some of the mid-00s KTMs with 48mm forks have three bushes in each fork leg, and they work like rubbish. The fix is to remove one of the bushes so the flex doesn't cause bind.
Worth mentioning that Geoff Ballard (and Jess Gardiner) run TTR RWUs on WRFs, and that (in 2007ish) Ben Grabham rated the XR250 as much better in rocks than the team CRFs.
Everything of this era has way too soft springs, unless you weigh 40kg... (Hondas are the worst, FWIW). Definitely the first thing to upgrade.
-
Okay guys. .. if I may please hijack this thread (sort of) ....
If I had a set of those 'crappola' Aus Spec 89 KX250 USD forks (which I do), what year model fork seal kit would I need to order if I were to get it from the USA? 1990???
Does anyone know?
Cheers.... :)
-
......why don't you just get a set in Australia for a 1989 kx 250 ???...why would you order fork seals from the U.S. ???
-
'89/90 USDs are 41mm.
Can't think of any other KYB RWU 41s. Maybe newer 85 USDs
Get 'em from your local dealer, not from the USA.
-
......why don't you just get a set in Australia for a 1989 kx 250 ???...why would you order fork seals from the U.S. ???
I am visiting the US in a few months. Why pay twice the price here?
That's why. ::)
Cheers Nath.
I think that answers it, but to be sure you're saying the 1990 US version of the 41mm KX250 USD are the same as the 1989 AUS ones?
-
......why don't you just get a set in Australia for a 1989 kx 250 ???...why would you order fork seals from the U.S. ???
I am visiting the US in a few months. Why pay twice the price here?
That's why. ::)
Mate they are $20 parts, why wait a few months to save $5 on a part that may not fit ?
-
LOL
Mate if you can get me a rebuild kit including seals, dust seals and all the bushings/o'rings for $20 then I will buy 3 sets from you.
There's always someone that can get it cheaper down the road.....
::)
-
Hey Hardo, If your visiting the US in a few months why wouldn't you buy a set of real forks mate! Get yourself a set of the 46mm ones & clamps to suit! Anyone that wouldn't do that while they were there would have to have rocks in their head buddy ;)
-
Strong words from Ando - but he's right.
Hell, Ando does have rocks in his head and even he knows to get the 46s!
;D
-
Where is the like button ^ :)
-
I see these sort of things seem to go cheap on E-bay but I would be interested to see how much US bike shops sell them for.
-
LOL Nath ...
Hmmm..... well I would be foolish to question you Ando ... I know what you have in your shed and I know that you know Green stuff!!
Are they really that bad? I noticed DB had a set of USD's on his 89 KX on the w/e .... Let me guess... they aren't std?
:)
-
Hardo, I was in he's shed the other night & as a matter of fact, he was working on them forks!! He told me to keep my mouth shut :o But I will say one thing, they were stock except for the harder springs. It's not the bike IMO, It's the rider! Although it all does help 8)
-
I'd be surprised if Burty's are stock, but he still doesn't rate them.
Early USDs suck because almost all of the flex is at the top of the chrome tube, so they bind as they go into the bushes in the upper leg. The 1990 models had mods to increase flex in the upper leg (at the bottom of the lower triple clamp) - the journos of the day didn't get it, but the engineers were trying to move some of the inevitable flex away from the moving parts.
Add in the need to fix the old-school thinking of soft springs and too-hard compression dampening which needs to be fixed, and you're most of the way to the cost of a set of US-spec 46s.
I wasn't until the 43mm USDs arrived in 1992(ish) that USDs were semi-OK. I'd argue that it took until the 46mm USDs came out in the second half of the 90s that they actually were an improvement in suspension actio over the 43mm RWUs from the late '80s.
So... 40/41mm USDs are pooh. Even the '88 KX RWUs would be hugely preferable. I'd hazard a guess that even a earlier set of damper rod forks with some cartridge emulators would be preferable...
-
They are stock Nathan, just with heavier springs. He was doing a re-valve the other night but they sent him the wrong parts. And yes he said they are average. I'm very happy with my US model 46mm ones could even be better with the right springs, very hard to get hold of the correct length. I'm not a big fan of spacers.
-
Where is the like button ^ :)
How's thing's Marty?
-
Awesome Ando..... are your marbles still rattled?
Do you still have the golf ball on your hand? ;D
-
Mate, you should see my helmet!! It really speaks for it's self. Shit in your head rattles when a CR500 lands on your head ???
-
Yep I saw your helmet mate .... pretty scary!!!
Glad you are ok!!! ;D
http://www.ebay.com/itm/KX500-KAWASAKI-1989-KX-500-89-FORKS-/310323322424?hash=item4840b61e38&item=310323322424&pt=Motorcycles_Parts_Accessories&vxp=mtr
-
There you go hardo easy fix cheap as chips ;)
you will have to past it through the boss first but ;D