Replacing fork seals

I'm replacing the seals on my 1985 Maxim and I have a few questions.
What is the amount of fork oil in each leg and/or height? Is the height with or without the springs in? Should the old fork oil (it has drain plugs) be drained first before dissembling?

Happy New Year to All, :lol: 2012

 

amount ? i don't know
most of these bikes are measured in OZ or CC, put the springs in before the oil, add a little oil pump the forks, add a little more.......
defiantly drain them, it might get messy, the little drain screw is easy to strip, the head and the threads, be careful

 

On my bikes. Progressive said to measure from the top five and 1/2 inches; no springs; forks collapsed.

 

only thing wrong with that is the spring better get to the bottom before the oil gets to the top

 

Welcome to the board....strongly suggest you buy a manual or get the XJ CD. Both of these will have the specs (fork oil qty) for your bike. Don't get too hung up on being one or two cc's out so long as both forks get the same amount.

 

so far I three answers for the fork oil capacity.
278 cc (9.4 US oz)
379 cc (12.8 US oz)
389 cc (13.2 US oz) a 1985 Maxim-X with progressive springs.
My bike has stock springs.

 

This is for stock springs

 

You can drain them when you take them apart, if you want to leave the drain-screws alone.

Whilst you're at it put in thicker oil (10W as chacal suggests).

To get better performance from your front end you could put some coins or similar on top of the springs (ie up the pre-load) before you put the caps/clips back on. (up to 1" of spacers/packing).

Just don't take your eye out on re-assembly.

You WILL need to obtain or make a special tool to get the internals out of the legs as there is an internal hex fitting in there.

Nige

 

Having just replaced seals and springs, I found the seals a real challenge to remove with out damaging/"buggaring" up the aluminum lower fork seal-seats and "rims".

I used heat -- as in a propane torch's application of heat -- to warm up the upper-lower fork around the seals, once "good and warm" -- like, nearly, but not quite too hot to the touch -- the seal gives up its old grip and it "prises" out much more easily...

However, this approach WILL "de-color" your clear coat, so only attempt this if you've don't have clear coat, or or gong to strip it anyway...

 

383cc's ~ 12.5 Oz.
10W --> (Or equivalent) Fork Oil

(I use Permatex Hydraulic Jack Oil)

Use an Impact Too and remove the Drain Screws.
Discard the Old Drain Screws.
(Replace with Stainless Cap Screws wrapped with Teflon Thread Wrap. Or,, ... Stainless Cap, Stainless Flat and O-ring.)

You can weld a 19mm BOLT to a Section of Steel Rod and fabricate a Fort Tool. (Nice to have)

You'll make less of a mess draining the forks before beginning work.

You have too be careful Pre-loading the Fork Springs.
There are some Adjustable Preloads that will fit the Yamaha Fine Threaded End-caps.

New ones are BIG-bucks.
But crazy kids are totaling their sporty bikes equipped with Adj-Preloads.
You can fill-out a Salvage Parts request.

Typical Adjustable Front Fork Spring Preload:

http://tyga-performance.com/site/produc ... ts_id=1142

 

That's excellent advice. When I'm doing forks in the shop I try to start them Friday afternoon. Get the wheel off, a pan under them, and let those suckers drain all weekend. Way less mess disassembling when they've had a lot of time to bleed out.

 

dmccoach...not sure what you're on about re seal difficulty? Having elevated the front end off the deck I unscrew the allen bolts that holds the lower fork sliders and the oil drains straight into a pan. The sliders then easily slide staright off leaving the seals and other bits on the upper forks....Am I missing the point?

PS You can lock two nuts together on the end of a piece of threaded rod to hold the damper internals (if you don't have access to a welder)

PPS lubricate the outside of the seal to help it seat into the fork slider. EBAY has plenty of seal drivers available by the way if you don't want to mess around with PVC pipe