Rear shock replacement

my amazing 82 650 csr survivor bike.100% original until i recently had carbs gone through. I never rode a kz650 beforeits great.weight,performance and so forth.it has original 38 year old shocks.only 13,000 miles.there are lots of dips in the residential streets here.i didnt slow way down when i hit one and bam! The rear suspension bottomed out.it reminded me of a spportster i used to own.is that typical.only 13,000 on the bike.i figured z1 has replacements.i am going to change fork oil.book says about 285ccs each fork.is it worth it to change fork springs with such low mileage? I love this bike. My dreambike is rootbeer and orange 73 but i cant afford that.

The original shocks on my 1977 KZ650 wore out in less than 10,000 miles (I'm the original owner). I have Hagon shocks (see image below) on it and they work GREAT! I've had them on it for more than 17,000 miles and they still work like new.

Regarding the front forks - you need to measure from the top of the fork tubes down to the fork oil rather than relying on a specific quantity of oil. It is a MUCH more accurate method. Consult the Kawasaki Service Manual for the specific measurement for your model bike. Ed

Whatever shocks you get, can you report back? I need to change mine as well. Thanks.
You probably ought to replace the fork springs at the same time as the shocks.
Nessism has mentioned the Sonic Springs. Progressive brand are another option, but the sonics are possibly better.

Fork specs. 1981-82 KZ650 FSM. 650-H2 = ~260cc Fork oil change. 280cc +/- 4 cc after disassembly & forks are completely dry. There's also measurements, but I just add the correct amount. I take apart the forks instead of just changing the oil. The manual specifies 10W, but you can probably go with 15W which is what I plan on doing.

Fork tools. Bottom allen bolt: use a hardened 8mm allen socket wrench or brake caliper socket. The head of the inner cylinder looks just like a 12-pt 19mm socket wrench, so you can use whatever fits that. I use a LH-threaded 1/2" bolt w nuts (the head of the bolt is 3/4" which is ~19mm). Some guys weld a nut to the threaded end of a long bolt.

martin_csr wrote: ................ you can probably go with 15W which is what I plan on doing.

Agree. I have always used 15w Bel-Ray fork oil in my KZ650 forks and it works great. Ed

650ed wrote:

martin_csr wrote: ................ you can probably go with 15W which is what I plan on doing.

Agree. I have always used 15w Bel-Ray fork oil in my KZ650 forks and it works great. Ed

+1, I use the same fork oil

Shocks could be work out at 13k miles, patiently search ebay every week for nos pair.

If possible do some research on what spring rates will work with your weight to give you the proper sag numbers for your bike.
Here's a video on a stock zx-10 from 2008 showing how different weight riders load the suspension differently.

Or contact Restocycle who has a ad at the top of each page here on KZRider
He is a IKON dealer
Dave