Dr_Jim wrote on 12/31/69 at 16:00:10:BTW -
It is possible to drain the front forks on the bike ...
There's an 8mm hex bolt at the bottom of the fork, but it's underneath the front axle, so the front wheel and axle have to be removed first.
Since I'd already jacked up the bike and pulled the wheel off to fit a Kenda 761 tire, I decided to drop the 8mm bolts and see what happened.
I attacked the right fork first with my trusty 8mm Tee-wrench - the bolt was torqued fairly well, and took some grunt to loosen, but it unthreaded easily once I'd broken it free.
Glorp! out poured a bunch of really nasty-looking fork oil, looks like you can drain these forks after all....
The left side turned out to be somewhat more of a problem, since the piece that the 8mm hex bolt was threaded into kept turning inside the fork, and the 8mm impact driver bit I had was too wide to fit into the fork, and it's hex part too short reach up inside.
No problem, time for "Instant Bubba Wrench... Using only hand tools commonly found in any workshop, you too can easily create a little piece of Arkansas in the privacy of your own garage!"
I used a 3' long aluminum pipe as a cheater bar on the 8mm Tee-handle wrench, and then as Wife Katherine dubiously held the wrench and cheater in place, wailed on it with a 2 Lb top-maul - "Whap! Whap! Whappity-WHAP! Ting!"
"What did you break, Honey?"
"The bolt free, Darling. Sorry to disappoint you ..."
The left fork drained as well as the right one, so I now had two empty forks to refill - removed the upper fork caps, and discovered that with low risers you have to unbolt the handle bars and move them back an inch or two to get the spacer tubes and springs out.
I followed the Clymer's instructions to "fully compress the forks before filling," but could not get more than about 200ml of oil in before the fork overflowed.
Mutter, mutter, mutter
Removed most of the excess oil with a Turkey Baster, then filled the forks the 'old school' way by putting in about two baster fulls (roughly 110 ml) in each side and working the forks up and down until the oil migrated into the lower part of the fork - it took 4 repetitions until the forks felt right, so I'm assuming that they have enough oil.
Yes, on a normal bike it's probably about as easy to just pull the forks off, but since I've got a steering damper, a fork brace, and a windshield (which was a total PITA to install) to fuss with, this seemed to be a little easier.
Cheers
Jim
Cheers Jim,
I'm somewhat curious here. I understand that with this method, that you used the fork springs to hold the slider in order to remove the 8 MM bolt. That also allows you to drain the oil.
You used a bunch of short cuts to avoid a more complex job. Got that.
I also understand the interference with the risers/handlebars because I have buckhorns. I just placed a mat on the tank and laid the bars back out of the way after removing the clamps.
But the manual states 441 ml in each fork and 75 mm from the top (with the tube compressed). Are you really content with only putting 1/2 the suggested oil in each fork?
BTW - I've decided that when I decide to replace seals or bushings and have the forks completely apart, that a nicely placed tapped hole in the bottom of the slider would be really nice. Then it will be like most of the older bikes that I work on anyway.