suzuki intruder 1500 1998

[DavisJim]

Hello, need help in how to replace front fork fliud? Do i need to remove the coil spring when filling then pump it a few times? Can the fliud just be drawn in though the little hole on top inside of shocks?..................jim

[DrBob]

If you have a fork oil syphon pump you can suck the fluid out the top after you remove the fork caps. But I prefer to remove them from the bike and use the 'dump and pump' method, then rinse them with a little fresh fluid, dumping and pumping again before putting in new fluid. It only takes five minutes longer to remove the front wheel and fender, and you know for sure that you got all the old fluid and any crud out of the forks.
While you have them off anyways, it is a good time to install Progressive brand fork springs for a radical improvement in ride quality. Best $68 I ever spent.

[omegajim]

I've read this needs to be done on regular basis. How crucial do you think this is?

......and the progressive fork springs, do they consist of two sets of springs or one spring with a variable spring rate?

[DrBob]

The Progressive springs are single springs that are progressively wound, so they give more that the stock springs over the small bumps but are stiffer than stock springs over the bigger bumps. They are also longer than the factory springs (you just use a hacksaw to cut the factory spacer to the correct length). You get a smoother ride, less bottoming, and better handling.

There is no factory interval for the fork oil, as in theory as long as the fork seals and dust seals are not leaking the oil never needs to be changed. But I like to change the oil and dust seals every couple years, as the dust seals deteriorate over time and you'll get some water leaking into the forks, which causes the oil to deteriorate. My fork seals seems to last several times longer when I keep the oil and dust seals fresh. I also like to play with the fork oil to get the best ride- the factory uses 10 weight, but I find 15 or 20 weight slows down the fork dampening a bit and is a great way to fine tune the front end for the riding you do.

[omegajim]

All very interesting, but I'll need a newer bike to consider this change. An old Yamaha isn't worth that level of effort. An old Yamaha is only worth the amount of effort to keep it running smoothly.

I only had to ask about the springs as I recall seeing dual spring suspension somewhere. It may have been in a specialty car shock, now that I think of it.