I'm sure a few of you have done this already ;-)
The new springs from Progressive arrived today. I have drained the old oil and pulled the old springs, spacers and washers.
Now for the spacer cutting; The meassure 5.12 inches, is that like 5 inches and 12/100 of an inch? Is it a decimal meassure?
And for the new fork oil level; how is this meassured? Springs and spacers in or out? Fork compressed or fully extended? How exactly do I meassure the oil level?
Quote from: Cannon on March 28, 2009, 09:36:51 AM
I'm sure a few of you have done this already ;-)
The new springs from Progressive arrived today. I have drained the old oil and pulled the old springs, spacers and washers.
Now for the spacer cutting; The meassure 5.12 inches, is that like 5 inches and 12/100 of an inch? Is it a decimal meassure?
And for the new fork oil level; how is this meassured? Springs and spacers in or out? Fork compressed or fully extended? How exactly do I meassure the oil level?
5.12 is the same as 5 1/8 (actually is 5.125), doesn't have to be exact but should be close. At 5.12 I was unable to tell much change, dissatisfied so much I immediately went back and cut new spacers longer for more preload. I have my measurements somewhere if you do a search and I posted some under the FAQ section of this forum.
Fork oil is measured with the forks empty, no springs, spacers or washers and fork compressed. Measurement can be made with any device you have marked or a tape measure from the top of the fork opening to the fluid level.
I also went with heavier fluid, stock being 10, I used 15 weight.
Cannon, the point that flew right by me was that when they speak of "oil level", what they are really measuring is the air at the top of the oil -- from the top of the tube down to the oil.
I used a small, adjustable, carpenter's square to measure mine. Laid the short side of the square across the top of the tube, with the long part extended. By setting the length before, you can simply fill until the oil just reaches the bottom of the long member of the square. Mine would only fit in the tube in the center, so the ambiguity of measuring the level in a tilted tube was also solved.
Thanks to both of you. I will search for the meassurement from Terry.
Will longer spacers increase the hight of the front-end? And will heavier forkoil include more stress to the fork rubber bushings?
QuoteWill longer spacers increase the hight of the front-end? And will heavier forkoil include more stress to the fork rubber bushings?
Unless your stock springs are broke or sagging they should be sufficent to hold your forks at their full extention at rest so the longer spacer will have no effect on height. The fork oil weight shouldn't affect the seals because the pressure is actually below the piston, the heavier weight oil just helps stiffen up the fork travel.
The following is from the tips & tricks section. It states that the forks should be compressed when meassuring the fork oil-level.
"
Refill the tubes with fresh fork oil, Progressive Springs instructions states a maximum level of 5.5" measured from the top of the fork tube to the top of the oil with the forks compressed without springs or spacers installed. You can make a simple dipstick for this.
"
Terry says forks should be fully extended. Which one is it?
Cannon,
I was in the garage helping Robert do his as we speak when I realized I told you incorrectly.
Fork fluid level is with the forks Compressed. I did modify my previous post for those reading.
You beat me to the post Cannon! lol
when I replaced my springs a month ago I cut my spacers to 5.25 and went with the 15wt oil. Made a big difference in the way the bike rides and stopped.Much better than stock.(http://i595.photobucket.com/albums/tt33/tmds3/cc_thumbsup.gif)
Robert put in 15 weight and cut the spacers 5 3/8's inch, I cut mine 5 1/2 inchs, I do like the extra preload.
Thanks to all of you helping out here. I just made my testride with new steelbraided brakeline, Progressive fork springs, 5 3/8 spacers and 10 weight fork oil. Big difference when braking. Less frontend dive and a lot firmer brake lever. Maybe I will try 15 weight oil later. Thanks again :grin:
I added a little length to the spacers to overcome the weight of the magnum tank. I can tell a big difference of my front end, but I am thinking even if I had just went with the stock springs I would have seen a difference just not as much as the progressive, :lol: or as Terry puts it aggressive progressive springs.
In other words I think my spring where worn out.
Just out of curiosity; When the fork is fully compressed to the bottom, is that the spring itself that is fully compressed, or is there something else in the forks that stops the compression? If it is the spring itself that limits the compression, then the plastic spacers will be heavily loaded, yes? And added preload by adding longer spacers would stress the spacers even more?
No, Robert, the springs are not the only limit on travel. With the tops off the tubes, the springs have nothing to push against. The fork has limited travel, and the oil level is to be measured with the fork all the way against the stop. ("Compressed" may be a misnomer here, in that the only force you are "compressing" against in this case is gravity...)