Front Suspension Refresh

[Turtleface]

Alright, finally got all the little annoying oil leaks (Woo hoo! No more oil on hot exhaust!) taken care of, with the exception of the valve cover gasket, which will be changed when I adjust the valves this weekend. Next project is going to be a front suspension refresh. First things first. How would I tell if my anti-dive is working correctly? When I brake, I get a nice steady feel at the lever, but the front end seems to bounce a bit while braking. Enough to make stopping a chore at times. It feels like the unit is switching back and forth between operating, and not operating. I can also dip the front end about 4-6 inches easily, if I grab a handful of lever. I planned on making block-off plates, with channels of course, and doing progressive springs with fresh oil, and proper adjustments. I was contemplating cartridge emulators, but I'm not terribly familiar with them, and frankly, have no idea what they do, or how they work, or why they might be desirable. Do they merely give you a greater degree of adjust ability? If so, I'll be all over it. Eventually, I'll be doing the GSXR front end conversion, but it's still many, many years away, and would like a bit of an improvement in the mean time.

It's hard to decide what I want to do to this thing more, wrench on it, or ride it.

[reddirtrider]

If the front is dipping that much it doesn't sound as if the anti-dive is working properly. This could be due to several factors among which could be your oil level. How long ago were the forks last looked at - 25+ years?

I've reused the anit-dive unints on the GS750ES I jsut rebuilt with no problems, however, there are those who do block them off and install heavier springs. It's really your choice.

Rebuilding the forks would probably be a good thing. You'll need oil and dust seals (I always replace the olkd dust seals as they are probably cracked at the sealing edge) along with fork oil. Not a difficult task.

There isn't much to really go wrong with the anti-dive units.

[Turtleface]

If the front is dipping that much it doesn't sound as if the anti-dive is working properly. This could be due to several factors among which could be your oil level. How long ago were the forks last looked at - 25+ years?

I've reused the anit-dive unints on the GS750ES I jsut rebuilt with no problems, however, there are those who do block them off and install heavier springs. It's really your choice.

Rebuilding the forks would probably be a good thing. You'll need oil and dust seals (I always replace the olkd dust seals as they are probably cracked at the sealing edge) along with fork oil. Not a difficult task.

There isn't much to really go wrong with the anti-dive units.

Yeah, I don't figure there's a whole lot that will physically go bad on it, mostly assumed it needed a good refresh. Bike sat in California for a few years before the PO bought it, and I know he didn't service the forks. Honestly, I doubt they've ever been opened up since Suzuki put them together. Dust seals are definitely seeping, nothing major, just wets the tubes a bit, doesn't run down the forks or anything, so I know they're shot. Looks like new oil and seals to start with, and see if that sorts it. Use the money I would spend on progressives to get started on stainless steel brake lines.

[reddirtrider]

Yeah, I don't figure there's a whole lot that will physically go bad on it, mostly assumed it needed a good refresh. Bike sat in California for a few years before the PO bought it, and I know he didn't service the forks. Honestly, I doubt they've ever been opened up since Suzuki put them together. Dust seals are definitely seeping, nothing major, just wets the tubes a bit, doesn't run down the forks or anything, so I know they're shot. Looks like new oil and seals to start with, and see if that sorts it. Use the money I would spend on progressives to get started on stainless steel brake lines.

Keep in mind if you do use the anti-dive units you'll need extra line (about 2 feet) and 4 more fittings if you're doing them yourself. Plus those things (anti-dives) are a bear to bleed. If found it easiest to remove the top half of the anti-dive unit and keep it vertical so the air will bleed out properly. This is even using a vacuum pump. Just a heads up.

[Billy Ricks]

There is also two sets of teflon bushing you should replace while you're doing this. You won't believe how nasty fork oil gets, probably the most overlooked maintenance on just about any bike.

The anti-dive works fairly similar to the way a wheel cylinder works on drum brakes. I did have one rust up enough at one time to where the piston wouldn't go down. I just had to clean it up to get it straightened out.