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Racetech valves

danny sparks

Can anyone tell me what the air gap is on a 1988 gtr1000 race tech valves in.front forks. Preferably fully extended. Thanks chaps


According to RT :

That is 150mm or 5.9 inches compressed with emulator in.

If you want to set by Kawasaki manual for 88 it is 355mm or 13.78 inches fully extended adding with emulator

I spoke to RT by phone and their recommendation is 150mm compressed for all years about two or so years ago.

Please if you would allow on a controversial note. I have done it both ways on my 87 with emulators. The procedures will
end in the same result with about 330 ml of oil from tube on draining. Some have argued this finding but such has been
my experience.

From their suspension bible, RT also recommends individual tuning by adding 10cc/ml at a time to tune for last third of fork travel to control break dive to your preference. Few go to this trouble.

Hope this helps as more than you asked.
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Oh bye de bye! According to Clymer's there is only 9 ml difference in early and late fork oil capacity empty and none on refill.
That from pg 351, Table 1.

Please forgive the detail. While working my way through college I was an Audio Visual librarian and also assisted students with citing paper references. In the days before internet no less. Just soooooo you all understand. It is a trained reaction to a question!


In the 1986 to 1993 the Kawasaki Spec is 355 mm / 13.97" with the fork extended, spring removed.
In the 1994 to 2007 the Kawasaki Spec is 171 mm / 6.73" with the fork compressed, spring removed.

NOTE: The earlier specs were done with the fork extended because of the location of the "crossover tube".
ie; At 355mm / 13.97" the crossover is above the oil level.

I've found that the later model {1994 to 2007} Kawasaki Spec works fine on all models and is easier to measure.
Because (at 171 mm / 6.73") the crossover is below the oil level, it will allow oil to flow between the 2 tubes as you set the level.
To overcome the issue. Allow the oil time to settle after you set each fork, and then re-check the level a second time.

(As Mercer said) RaceTech uses the Later model method to service the forks.
Using that method, they decreased the Oil Level from 171 mm / 6.73" to 150 mm / 5.90" with the fork compressed, spring removed.
(The Oil Level is higher to prevent Brake Dive).

If you prefer to use the earlier method, (My guess is) the (Race tech) oil level would be 334 mm/ 13.15" with the fork extended, spring removed.
I suggest (after servicing) you confirm the Oil Level is approx. 150 mm / 5.90" with the fork compressed, spring removed.

Ride safe, Ted
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