GPZ1000RX Help and info anyone?

[Noxious89123]

A friend has got a GPZ1000RX 1987 I think.

Of what i can find, the tyres should be 120/80-16 and 150/80-16. ANyone know of some decent rubber in those sizes? It's currently got an Avon on the rear and a Bridgestone on the front, no sure if they're the right size or not. They both have plenty of trear left, but we think they're quite old.

The bike feels a bike unstable at anything other than low speeds. What could be causing the problem?

After a quick Google, I think it may be relate to the anti-dive units? Apparently they can seize, making the suspension rock solid.
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'06 Honda CBR125RW-6 ~ '00 Honda CBR600F-Y ~ '07 Honda CBR600RR-7 ~ Bikeless
'53 Ford Ka 1.3 ~ '03 Vauxhall Astra SRi 1.8 ~ '52 Vauxhall Astra SRi 2.2 ~ '53 Vauxhall Astra GSi

[hmmmnz]

[temeluchus]

I had a GPz750R which has the same antidive. to test its working ok, roll the bike back and forth and as you roll it forward apply the brakes. If the forks stiffen up thats a good sign.

At a stand still compress the forks, then try again with the brakes applied. With the brakes applied try again, the forks should be nearly rigid.

The units can be bypassed but it needs a special plate-you cant just blank them off as this ruins the damping circuit in the forks.
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Some shite cruiser. Now with guns and FREEDOM!

[virus]

[Noxious89123]

Roger roger!

Won't be replacing the suspension on it, as the bike only cost £200.
____________________
'06 Honda CBR125RW-6 ~ '00 Honda CBR600F-Y ~ '07 Honda CBR600RR-7 ~ Bikeless
'53 Ford Ka 1.3 ~ '03 Vauxhall Astra SRi 1.8 ~ '52 Vauxhall Astra SRi 2.2 ~ '53 Vauxhall Astra GSi

[Noxious89123]

[hmmmnz]

no no, blank it off wont make it rock solid.
it needs brake pressure to push the piston into the fork,
with out that pressure, the piston isnt pushed into the fork and the forks will act as normal forks do
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the humans are dead
I kick arse for the lord
Wiring Diagrams BIDNIP it bitches

[temeluchus]

The Kawasaki Anti dive requires a special plate to replace the units as MOST of the damping oil goes through the unit. If you were to remove the unit and fit a flat plate, effectively you would remove allmost all the oilway through the damper.

The end result will be forks that are almost rigid until the fork seals blew.

You can disable the unit by running a brake line direct to the caliper, but make sure to bung up the hole where the banjo went with another bolt or some sort of plug. But leave the unit in place.

Every other antidive ive seen, ie any of the suzuki ones, dont affect the damping nearly so much-so can be banked off without harm. This is NOT true with the GPz ones.
____________________
Some shite cruiser. Now with guns and FREEDOM!

[Noxious89123]