1980 kz750 twin fork oil capacity

I'm trying to figure out how many cc's of fork oil to put in my kz750 front end. I just disassembled them, and cleaned everything and changed the fork seals, now I can't for the life of me find out how much fork oil to put in them. Any help would be greatly appreciated.

You need to get a hold the Kawasaki Service Manual for your bike (you may even be able to find a free PDF version online). The volume of the fork oil is just a rough estimate. You actually measure the fork oil level by inserting a rod in the tube with the forks on the bike; the front end off the ground and the forks fully extended. You use the rod to measure from the top of the fork tube to the oil level, similar to checking the motor oil on a car. The manual will show you the correct distance from top of tube to oil, and it will show whether the springs should be in or out because some measurements are done with them in; some with them out depending of the model and the manual. After you measure and fill to the correct level you ride the bike for a while and check again and adjust as needed. This is because air can get trapped in the nooks and crannies and riding tends to push it to the top of the forks. Be sure to use the manual for your exact year/model because they may not all be the same. Ed

The following links may be used for help with downloading an FSM (which will contain the fork oil volume).

Later, when satisfied that the volume is correct, would use a thin wood dowel to fab a dip-stick whereby levels may more easily be maintained in the future.

FSM might provide measured level distance from top of tube, but sometimes a manual provides only the correct volume -- wet refill volume and/or dry refill volume -- without mention of the resultant measured level.

kz750twins.com/?p=15

biquetoast.com/cgi-bin/750ManualList.cgi

Good Fortune!

140mm from the top of the tube, springs out, forks fully compressed, 10 weight (15 if you are over 220lbs). If there is too much brake dive add 10mm of fluid and try it again. Fresh springs?

80B4 wrote: ... springs out, forks fully compressed....

Removing and replacing oily springs is a messy exercise that can be avoided when the correct level at full extension with spring left in is also known.

IMO, all the manuals ought to also provide the measure of fork oil level from top of the tube with the springs left in. But some don't. And that's where the wood dowel dip-stick again comes in handy, marked for use with springs left in.

Changing fork oil (flushing and re-filling) -- remove drain screws; wrap rags around fork legs at drain screw levels to catch emerging filthy oil; vigorously pump forks; replace drain screws; support front end at full extension (tire off floor) so it won't collapse when suspension is removed (a support and/or jack under the engine should work just fine); remove fork caps; fill each fork to level easily determined by dip-stick without removing springs; replace fork caps; lower front end onto normal suspension.

Good Fortune!

80B4 wrote: 140mm from the top of the tube, springs out, forks fully compressed, 10 weight (15 if you are over 220lbs). If there is too much brake dive add 10mm of fluid and try it again. Fresh springs?

Fully compressed??? I don't think so. Don't you mean fully extended? I've never seen specs where you fully compress the forks. Ed

Patton wrote: ...Changing fork oil (flushing and re-filling) -- remove drain screws; wrap rags around fork legs at drain screw levels to catch emerging filthy oil;

I used to make "deflector curtains" out of a couple of folded paper towels and tape them to each fork tube so the squirting oil would hit them and drop down. Otherwise it shoots about eight feet across the floor. :ohmy:

Fully compressed??? I don't think so. Don't you mean fully extended? I've never seen specs where you fully compress the forks. Ed[/quote]

Yes, fully compressed. 140mm from the top of the tube, spring out, fully compressed. Every fork tuner I use ( race-tech, traxxion and others) specs that way. Do some research, you will see.

buffalowinger wrote: I'm trying to figure out how many cc's of fork oil to put in my kz750 front end. I just disassembled them, and cleaned everything and changed the fork seals, now I can't for the life of me find out how much fork oil to put in them. Any help would be greatly appreciated.

I copied the pages from my 1979 750 twin factory manual. Probably similar for yours, no guarantees. You do put the front end up on a jack to clear the front wheel then check oil level with a dipstick method.

Second page showing level check:

650ed wrote:

80B4 wrote:

80B4 wrote: 140mm from the top of the tube, springs out, forks fully compressed, 10 weight (15 if you are over 220lbs). If there is too much brake dive add 10mm of fluid and try it again. Fresh springs?

650ed wrote: Fully compressed??? I don't think so. Don't you mean fully extended? I've never seen specs where you fully compress the forks. Ed

80B4 wrote: Yes, fully compressed. 140mm from the top of the tube, spring out, fully compressed. Every fork tuner I use ( race-tech, traxxion and others) specs that way. Do some research, you will see.

You're simply wrong - see examples below. Show me a Kawasaki manual that does NOT say measure with the front wheel off the ground. - I'll wait for it. Do your own research and get back to me. But don't give me that old "I know a guy who knew a guy who had an uncle who went to races and a guy there told him he once talked to a tuner who knew a guy......" Show me the printed words from the manufacturer that gives the specifications for the 1980 KZ750 twin. :laugh: :laugh: :laugh: Ed

"I know a guy who knew a guy who had an uncle who went to races and a guy there told him he once talked to a tuner who knew a guy......"

:laugh: :laugh: