1982 GS1100G 37 mm fork oil weight and volume.

[RichDesmond]

Yep, no air, it's not needed.

[mmattockx]

So installed a set of sonic's 1 kg springs . Cut the preloads as to sonic's directions with 1/2" preload , filled forks to 12lb psi and 8.6 oz 10 weight each side. Ride is 100% better.

You don't run any air pressure with the Sonic springs, let it all out.


Mark

So installed a set of sonic's 1 kg springs . Cut the preloads as to sonic's directions with 1/2" preload , filled forks to 12lb psi and 8.6 oz 10 weight each side. Ride is 100% better.

[mmattockx]

in the maunual it talks about flushing the forks . what product to use is not mentioned.

I use kerosene, it doesn't damage seals and works great for removing the crud. As Rich says, dump old oil, fill with kerosene and stroke the fork for a bit, then dump out and let drain fully.


Mark

[RichDesmond]

All great stuff. . . messed with a couple.differnt lengths of spacers and the fresh 15 weight i had on hand. Front end still sucks . So going to order up a set of the 1.0 springs.Thanks again for the link. Seals are still good . in the maunual it talks about flushing the forks . what product to use is not mentioned. Mineral spirits ? Then blow it out. I got the long weekend to mess with it ... Figure 10 days with the 4th before new springs show up and i will get to bolt everything toghere. It looked to be 35 year old fork oil when i did the initial drain.

Some ATF works well to flush. Pump the old oil out (fork leg inverted) put some ATF in, cycle the forks through their travel a few times and pump it out.

All great stuff. . . messed with a couple.differnt lengths of spacers and the fresh 15 weight i had on hand. Front end still sucks . So going to order up a set of the 1.0 springs.Thanks again for the link. Seals are still good . in the maunual it talks about flushing the forks . what product to use is not mentioned. Mineral spirits ? Then blow it out. I got the long weekend to mess with it ... Figure 10 days with the 4th before new springs show up and i will get to bolt everything toghere. It looked to be 35 year old fork oil when i did the initial drain.

[RichDesmond]

aH Hah!..... so I'm not on the wrong planet after all

I pull the emulators out with my pully tool as well, but I have my calibrated suction stick (piece of tape) that I recheck oil levels after.
I change oil every couple of years as well, (when I do brake fluid). nice to have drain plugs in the forks, newer bikes don't.

Even on bikes that have drain plugs I rarely use them. I do fork oil changes when I put a new front tire on. At that point I have the wheel off (and on some bikes the fender too) so it's just a few more bolts to loosen and the forks are in my hand. Actually faster and easier to do it that way than waiting for it to dribble out of the drain hole.

[derwood]

If I was just changing the level a little I probably wouldn't pull forks off. If doing a full change to change weight, I would. No need to mess with oil at all when adjusting emulator (I use one of those 4 prong grabbers to pull the emulator out, and pulling the spring out slowly doesn't lose enough oil to worry about) so no need to pull forks there either.
Doesn't matter what kind of springs you have.

aH Hah!..... so I'm not on the wrong planet after all

I pull the emulators out with my pully tool as well, but I have my calibrated suction stick (piece of tape) that I recheck oil levels after.
I change oil every couple of years as well, (when I do brake fluid). nice to have drain plugs in the forks, newer bikes don't.

[RichDesmond]

so if I want to see how 20mm higher fork oil level is going to behave you are suggesting I take off the front wheel pull the forks out and ad oil, reassemble. Or if I want less rebound damping say so I go to 10w instead of 15w same drill?
how about when I pull the emulator to ad a turn, or back off 1/2 a turn? gotta take out the spring, going to lose a little oil.
it ads more than 10 minutes, I still don't see the point, I could do the trigonometry instead.

I can see the argument if I was changing seals anyways, ( i would check again after installation for a base line. then again after a good ride because sometimes the oil level drops after complete overhaul) but for playing around ...... for me, no way.
still think its a little ridiculous but then I don't have Sonic Springs...

If I was just changing the level a little I probably wouldn't pull forks off. If doing a full change to change weight, I would. No need to mess with oil at all when adjusting emulator (I use one of those 4 prong grabbers to pull the emulator out, and pulling the spring out slowly doesn't lose enough oil to worry about) so no need to pull forks there either.
Doesn't matter what kind of springs you have.

[derwood]

It's not ridiculous, it's the best and most accurate way to do the job. It's also very easy. You can have the tubes off the bike in 10 minutes.

so if I want to see how 20mm higher fork oil level is going to behave you are suggesting I take off the front wheel pull the forks out and ad oil, reassemble. Or if I want less rebound damping say so I go to 10w instead of 15w same drill?
how about when I pull the emulator to ad a turn, or back off 1/2 a turn? gotta take out the spring, going to lose a little oil.
it ads more than 10 minutes, I still don't see the point, I could do the trigonometry instead.

I can see the argument if I was changing seals anyways, ( i would check again after installation for a base line. then again after a good ride because sometimes the oil level drops after complete overhaul) but for playing around ...... for me, no way.
still think its a little ridiculous but then I don't have Sonic Springs...

[RichDesmond]

there is no way you have to pull the fork tubes off the bike to check and / or adjust the oil level. or even change it for that matter...

proper way or not that would be ridiculous.

?? I thought I was on your ignore list??

It's not ridiculous, it's the best and most accurate way to do the job. It's also very easy. You can have the tubes off the bike in 10 minutes.

[cowboyup3371]

there is no way you have to pull the fork tubes off the bike to check and / or adjust the oil level. or even change it for that matter...

proper way or not that would be ridiculous.

?? I thought I was on your ignore list??

Unless you are going to change the seals which means you have to change the fluid at the same time

[bwringer]

held vertically? you've got to be kidding....

If you don't want to remove the forks, then just be careful about where you slurp the oil from. On my fork oil level tool, the tubing is zip-tied to a stiff wire so I can be somewhat precise about where I draw the oil from. Slurp from the middle and it's the same as if you're holding the fork leg vertical. Subtract a few mm and slurp from the back.

[derwood]

Since the proper way to do this involves removing the fork tube from the bike, it's really rather easy to hold it vertically.

I will second bwringer's recommendation on Sonic springs and 10w oil. Since the 850 is a few pounds heavier than your 1100, and I have added a bunch more weight to the front (frame-mounted fairing), I also went with the 1.1 rate springs. Brian (bwringer) needs the stiffer springs due to riding style, I need them for the additional weight on the bike. The 10w oil is great.

I also agree that it is the LEVEL that is more important than the amount. Some will say that the level needs to be within 1mm or so from side to side, I'm not so sure it needs to be quite that precise, but certainly as close as you can get them.

.

there is no way you have to pull the fork tubes off the bike to check and / or adjust the oil level. or even change it for that matter...

proper way or not that would be ridiculous.

?? I thought I was on your ignore list??

[RichDesmond]

... Some will say that the level needs to be within 1mm or so from side to side, I'm not so sure it needs to be quite that precise, but certainly as close as you can get them..

You're right, anything within 3-4mm is fine.