Replace fork fluid 95 Nighthawk.

[bortustortus]

Hello, I'm diagnosing a "squirrely" CB750 Nighthawk. Front end bearings have no play. The front forks seem soft and I'd like to change the fork fluid. I cannot find guides online or in my manual for changing the front fork fluid, only showing the fluid filling process while replacing or rebuilding the forks. I can find generic videos online but they all remove the fork from the bike. The seals seem to be in good condition and I feel like there should be some way of draining the fluid and refilling without removing from the bike. The manual shows a drain bolt located on the lower side of the slider. Could I just crack open the drain bolt, fork cap, and compress the forks until it's drained? How would I go about measuring the level of fork fluid while adding new fluid? Will those syringe fork fluid tools work for this? Thanks all.

 

[Biebs]

Yes drain fluid and refill from the top. Do not remove both fork caps at the same time as front end will drop.
Or you can support front end from ceiling joist.

I have a 4 inch pvc spacer in my 92 nighthawk forks stiffens up the front forks.
350 to 400cc of fork oil or measure what you drain.

I use ATF in my fork dextron 3 you can also use ford type F ATF.

ATF is the correct fluid


Do not need to spend big money on special fork fluid.

Correction : fork fluid amount 200cc. 6 to 8 ounces

 

[bortustortus]

Hi and thanks for the quick response. Got it, do one fork at a time. Do I need to remove the fork cap while draining to let the fluid out, or remove it after drained to refill it? Previous owner said front forks were rebuilt, I question if he put the correct amount of fluid in it. Could I measure total fluid in fork while still assembled and on the bike? Most guides I find show adding and measuring fluid with fork removed.

 

[brettp]

Doesn't matter. As long as you're doing one fork at a time.

 

[BIKERDAD]

Watching this as I need to do my forks as one is leaking also iv taken them right off as I'm having them powerd coated to match the frame . (As cos there snowy affect pitted lol ) .

 

[bortustortus]

Hello, the Clymer manual does show how to change the fork fluid, it's listed under maintenance instead of steering/front suspension. I've got new fluid in my forks and the ride feels better, but unfortunately did not fix my wobble. The bike wobbles over 20mph when I remove my hands and it drifts to the right. I've aligned my wheels following online videos, although maybe I should do it again after changing the fork fluid. I can't tell if my front tire is cupping or if I'm just trying to find an issue with it. I've attached a picture of it. This is the front wheel viewed from the front, the tire is only two years old and the bike has 17k miles total so I don't think it's had much on it. I've checked the air pressure as well. Thanks all, you guys reply quicker than any forum I've ever used!

 

[BIKERDAD]

Hi m8 I can't help on this one .as I can't see much wrong with it but if you feel the tyre you should feel bumps. If it's been sitting a long time mabye it sitting damaged the tyre not been used much ??