Well, I have a 1987 1000f. It has 24,xxx miles on it and I don't think the fork oil has ever been changed. I have tried to use the air preload and the air slowly leaks out over the course of 3-4 days. However, I like the ride without any air in it, but I think a heavier of thicker oil may make it handle the horrible bumps a little more here in Arkansas.

What oil do you suggest for the forks?

What should I replace while in the process o changing the oil?

What would should be replaced to fix the slow leak of the preload air?

Could anyone post a brief "walkthrough" of changing the oil? I know about the drain bolt in the bottom, but how do i go about refilling the forks?

Any help you offer is much appreciated!!! Thank you all in advance!!!

Alex

 

The best Fork Oil IMHO is Motorex Synthetic.

The standard oil for CBR is actually listed at ATF Fluid which is around 7wt. Just about everyones finds this too soft. I would use a 10wt if you are average size and a 15wt if you are a Bargeass.

Never worked on Air assisted forks, but it would probably be fork seals.

As for a walkthrough, I cant be arsed as its midnight. But if what you say is corrent and the fork oil has never been changed. One thing to remember is that fork oil has been in your bike picking up crap for 19 years. When I first got my bike (and it was only 8 years old at the time) my forks were pulled apart and the insides were like wet cement. Just a ****load of sludge in the bottom. Sure you could put new oil in but It would get all the crap out.

For about 3 hours labour plus a pair of seals a mechanic can pull them apart and clean out all the internals. By all means pull the forks off, but leave the rest to them and you wont need to touch it for a long time.

Cheers
Rob

 

My advice is if it aint boken dont fix it.
The above advice is overkill on a -87 bike.
Drain the oil, fill in new oil by simply pulling the top nut stretching the spring and pour the new oil where it is a gap.

 

A, Hmmmm, I couldn't sleep at night if I had leaky seals and didn't change 'em... and the slider wipers, and check the bushings by grabing the top and bottom of the alum slider, and rocking it back and forth,against each hand, and flushing out the crap in the bottom of the slider(it's there...) good quality fork oil has "stiction reducer propertys too. Get dirt or street fork oil, whch ever is cheapest

For me, when it comes to suspension, it may save your life... Had a speed wobble at 105, thought it was stearing stem bearings... turned out to be total sloppy slider bushes from long term trash oil. scarry !!!!!!!!!!!

I feel "older suspension needs a compleat inspection, when problems start showing up... Good hygiene!!!
Slider wipper looses tension, dirt gets in, seals fail, cant air up preload, low dirty oil, gives bad compresion and rebound dampning and eats seals/ bushings, not flushing, leaves the worst of contaminates to continue decay/ trashing new parts. ARRRRGH !!!!!!!!!!!! my 84 vf1000f and gsx 1100ez forks are now, like new. cbr next... Clean and free, Ripp'n PS. IMHO, the wooosh sound, feel and peace of mind, are worth the time and investment!!!!!!!!!!!!