TOPIC:

Going to replace the fork oil and seals. I have a KZ750 B1 but the forks are from a KZ750 H (not sure of the year-'80 or '81). What is the best oil to use for these? And how much? Thanks in advance for any suggestions.

This should answer your question

Thanks for this!

Here is mine with 05 gsxr1000 front with cognito front hub and KZ hoop. I haven’t had an issue with ground clearance. Zrx1100 swingarm and a 180 rear tire

The manual says to use 10W fork oil, but some guys go with 15W. I use Bel-Ray fork oil. The 750-4 pdf manual has the fork free spring length spec. To pull the seals I use an off-the-shelf seal puller from the auto parts store & use milk jug plastic to protect the fork tube lowers. A small scrap of wood could be used, but the plastic works better. Be sure to use a hardened allen socket or brake caliper socket to remove the bottom allen bolts. a cheap tool could twist & damage the bolts.

1981 KZ650-CSR forks. the 750H forks should be the same.



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martin_csr wrote: The manual says to use 10W fork oil, but some guys go with 15W. I use Bel-Ray fork oil. The 750-4 pdf manual has the fork free spring length spec. To pull the seals I use an off-the-shelf seal puller from the auto parts store & use milk jug plastic to protect the fork tube lowers. A small scrap of wood could be used, but the plastic works better. Be sure to use a hardened allen socket or brake caliper socket to remove the bottom allen bolts. a cheap tool could twist & damage the bolts.

1981 KZ650-CSR forks. the 750H forks should be the same.

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Where can I get the inertool from?

gordone it´s the screw with the two nuts threaded in the socket

Where can I get the innertool from?

Note: that homemade fork tool does not fit all forks. Assuming your forks are the same:
It is very simple >> Left-hand reverse threaded bolt w nuts. plus masking tape so it fits tight inside of a socket wrench.
The head of the inner cylinder is the same as a 19mm 12-pt socket wrench. use whatever fits that size socket. so get a bolt with 19mm head.
Someone else used a long bolt w a nut welded to the end of the bolt (see new pic. welded nut not shown).
In the USA. I used a 1/2 inch SAE bolt. a 3/4 inch wrench fits the bolt head. 3/4 inch = 19mm (approximate).
Note: bolts are sized by the diameter of the shaft, not the head of the bolt.


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I used a broom handle and that worked for me.

I've had success using just an impact wrench too.

What is these part, make the spring more stiffer ?
I don`t have it...

Fork spring spacer. It adds tension to the fork springs. When installing the fork caps, you should feel the spring tension.
You'll have to decide if the spacers are needed. Someone may have installed longer springs or something. ???



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martin_csr wrote: Fork spring spacer. It adds tension to the fork springs. When installing the fork caps, you should feel the spring tension.
You'll have to decide if the spacers are needed. Someone may have installed longer springs or something. ???...

The spacers are definitely required, they were there from the factory on the 750 LTD models. They shared the spring with other models with shorter forks, and therefore needed the spacer for the longer forks of this model.

Just re-read gordone's question and martin_csr's answer again. martin_csr is right, you'll just need to see how much tension is on the spring. If it's the original spring you'll need to make something up to replace it.