squishy forks

martin_csr wrote:

650ed wrote:

martin_csr wrote: You can get some Progressive springs. I've seen fork springs at Z1Enterprises.com but can't seem to locate them.
If you get new springs, it might be a good idea to upgrade the rear shock absorbers as well. Otherwise, you may end up with a firm front end & a mushy rear.

I rebuilt the forks on my 81 650 & used the specified 10W fork oil. The springs were well within the service limit. I'll use 15W next time, but the bike probably needs a suspension upgrade.

I read this and thought - I just checked the genuine Kawasaki KZ650 manual this morning and verified that it specified 15W fork oil before posting my answer in this thread, so why would Martin say "specified 10W fork oil?" Was he using a Clymer or Haynes manual? Then I though - just for once, before I shoot my big mouth off disputing someone's information let me do a bit more research. Here's what I found. The Kawasaki KZ650 manuals are all over the place regarding the fork oil weight. In them I found multiple places where SAE 10W; SAE 10W20; and SAE 15W were specified. So Martin's assertion of "specified" is also true. Personally, I've always used 15W Bel Ray fork oil and have been very please with the results. Ed

The "specified" comment was in regards to the 81 KZ650 - as mentioned in the reply. And the info is from the genuine Kawasaki factory service manual - it says to use SAE 10W (pg 2-21 Table 2-12). Next time I'm using 15W.