COG listserv faq, rear shock

The care and feeding of the:

Rear Shock
	From Mark Cipriano: Hey everybody! If you've changed the oil in your rear shock, please e-mail me or reply to the digest telling how much oil you used! Here's why - I changed mine, and got 8 oz out. Of course, the K manual says nothing about changing it, when and how, or how much oil it takes. Changing it is simple - I wish changing the engine oil was as easy (of course, once you get the rear wheel off; I did mine in conjunction with a rear tire replacement, so no loss). Anyway, a friend changed his and got about 3 ounces out. As we discussed possibilities as to why the difference (he had no visible leaks)... one of which was Big K's use of QC... anyway, I found he used Doug Freemans method of inverting the shock and removing the shrader valve from the air hose. I, on the other hand, removed the air hose from the shock. Now we wonder if maybe he got an air lock that kept the fluid from flowing. As the hose is much smaller in diameter - especially at the metal fitting that goes into the shock, its a good possibility. As I removed the hose, I had about a 3/8" hole for the fluid to flow from. Anyway, he's going to try my method and see if he gets more out. He mentioned he runs his rear air pressure at 40 psi, while I run mine at 7 psi. Could be he's making up for having less fluid! Let me know! This will make a good input for Guy to use in the Concourier, so I'll keep him informed. Mark Cipriano COG #1586 / Safety Director AMA 458655 From Mark Cipriano: >Dan Pritts wrote: "did you get any replies to the amount of rear shock oil >you are supposed to use?" Dan; Just did an hour ago! Sam Ellington "re-did" his. He was the one who only got 3 ounces out of his, mine was 8 oz. Well, he retackled it. This time he unbolted the air hose from the shock housing, and inverted it. He did get 8 ounces out! And quite dirty, no less. He says he noticed a nice difference in riding on it. Be sure to bleed the air before disconnecting the hose. Also, it's a lot less work to do it when removing the rear rim for a tire change... then it's a simple 20 minute job. Otherwise, as in Sam's case, it was a comfortable 2 hours. I used 10 weight (Belray) "racing suspension fluid" It comes in 5, 10, 15 and 20. I don't think fork oil is the same stuff. As I usually ride alone (wife has a dysfunctional disorder about motorcycles not doing anything for her...shhhh.), and weigh 130 pounds wet, I went thin weight. Good luck. It helps to have a second pair of hands to raise the swingarm to reconnect the shock (not required though), but be sure to get the shock installed before putting the rear rim back on! Imagine that's not fun! Mark Cipriano COG#1586 / Safety Director From John O'Keefe: >Sam Ellington "re-did" his. He was the one who only got 3 ounces out of his, mine was 8 oz. >Well, he retackled it. This time he unbolted the air hose from the shock >housing, and inverted it. He did get 8 ounces out! And quite dirty, no less. I did this twice on my 86 and found it helpful to also hang the shock inverted and warm it up a bit with a hair drier. You will get more complete drainage if you let it hang for a couple of hours AFTER you think you got it all. This may yield another ounce. Just a suggestion. >I used 10 weight (Belray) "racing suspension fluid" It comes in 5, 10, 15 >and 20. I don't think fork oil is the same stuff. Bel Ray specifically recommends the RSF for use in shocks rather than their fork oil for best results. > and weigh 130 pounds wet, I went thin weight. As a point of reference for the other list members, I weigh 170 and found the 15 wt worked well for me. >Good luck. It helps to have a second pair of hands to raise the swingarm to >reconnect the shock Try a small hydraulic jack to gently compress every thing into position for reinserting the bolts. If you are working without "extra hands" it makes the job much easier. Remember the upper shock mounting bolt gets torqued to 29 ft lbs John O'Keefe 95 Concours 94 Vulcan

Rear Shock

From Mark Cipriano:

Hey everybody! If you've changed the oil in your rear shock, please e-mail me or reply to the digest telling how much oil you used!

Here's why - I changed mine, and got 8 oz out. Of course, the K manual says nothing about changing it, when and how, or how much oil it takes. Changing it is simple - I wish changing the engine oil was as easy (of course, once you get the rear wheel off; I did mine in conjunction with a rear tire replacement, so no loss).

Anyway, a friend changed his and got about 3 ounces out. As we discussed possibilities as to why the difference (he had no visible leaks)... one of which was Big K's use of QC... anyway, I found he used Doug Freemans method of inverting the shock and removing the shrader valve from the air hose. I, on the other hand, removed the air hose from the shock. Now we wonder if maybe he got an air lock that kept the fluid from flowing. As the hose is much smaller in diameter - especially at the metal fitting that goes into the shock, its a good possibility. As I removed the hose, I had about a 3/8" hole for the fluid to flow from.

Anyway, he's going to try my method and see if he gets more out. He mentioned he runs his rear air pressure at 40 psi, while I run mine at 7 psi. Could be he's making up for having less fluid!

Let me know! This will make a good input for Guy to use in the Concourier, so I'll keep him informed.

Mark Cipriano COG #1586 / Safety Director AMA 458655

From Mark Cipriano:

>Dan Pritts wrote: "did you get any replies to the amount of rear shock oil
>you are supposed to use?"

Dan;

Just did an hour ago! Sam Ellington "re-did" his. He was the one who only got 3 ounces out of his, mine was 8 oz.

Well, he retackled it. This time he unbolted the air hose from the shock housing, and inverted it. He did get 8 ounces out! And quite dirty, no less. He says he noticed a nice difference in riding on it.

Be sure to bleed the air before disconnecting the hose. Also, it's a lot less work to do it when removing the rear rim for a tire change... then it's a simple 20 minute job. Otherwise, as in Sam's case, it was a comfortable 2 hours.

I used 10 weight (Belray) "racing suspension fluid" It comes in 5, 10, 15 and 20. I don't think fork oil is the same stuff. As I usually ride alone (wife has a dysfunctional disorder about motorcycles not doing anything for her...shhhh.), and weigh 130 pounds wet, I went thin weight.

Good luck. It helps to have a second pair of hands to raise the swingarm to reconnect the shock (not required though), but be sure to get the shock installed before putting the rear rim back on! Imagine that's not fun!

Mark Cipriano COG#1586 / Safety Director

From John O'Keefe:

>Sam Ellington "re-did" his. He was the one who only got 3 ounces out of his, mine was 8 oz.
>Well, he retackled it. This time he unbolted the air hose from the shock
>housing, and inverted it. He did get 8 ounces out! And quite dirty, no less.

I did this twice on my 86 and found it helpful to also hang the shock inverted and warm it up a bit with a hair drier. You will get more complete drainage if you let it hang for a couple of hours AFTER you think you got it all. This may yield another ounce. Just a suggestion.

>I used 10 weight (Belray) "racing suspension fluid" It comes in 5, 10, 15
>and 20. I don't think fork oil is the same stuff.

Bel Ray specifically recommends the RSF for use in shocks rather than their fork oil for best results.

> and weigh 130 pounds wet, I went thin weight.

As a point of reference for the other list members, I weigh 170 and found the 15 wt worked well for me.

>Good luck. It helps to have a second pair of hands to raise the swingarm to
>reconnect the shock

Try a small hydraulic jack to gently compress every thing into position for reinserting the bolts. If you are working without "extra hands" it makes the job much easier. Remember the upper shock mounting bolt gets torqued to 29 ft lbs

John O'Keefe
95 Concours
94 Vulcan

Back to the List FAQ page

Comments, problems to: Rick, or webmaster@concours.org