Bottoming out.

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I just recently rebuilt my rear shocks...took about an hour.......followed the manual instructions (80 - 81 Service Manual) added the recomended fluid and reassembled and installed...now rides better I add about 35 lbs air......whe I used to race dirt bikes in the early years (before air was added to shocks by manufacturers we used to mod the fornt shocks by drilling and adding a schrader valve to the top cap so air could be added. Adding air to the shocks did only one thing for preformance.... it helped the shock rebound faster which helped handle the rough terrain... the shocks would extend faster so that they would be ready for the next bump, rut or log.... Bottoming out was usualy an oil problen... (low, too thin or too thick) we used to play with these factors to compensate for terrain...
 
My shock compressor worked! Wow, suprised the heck out of me. I don't have metal workign tools or welders, but I do have wood tools. I made two end pieces of about 4 inch square pieces of 3/4" plywood. I drilled 4 holes in the corners through each one. Then I used a hole saw to drill a 2 1/8" hole through on eof them. 2 3/16" is probably more correct, but this worked. Then I put 4 pieces of all thread 3/8" dia each about 2 foot long. I put a pipe clamp in the other end to hold the bottom of the shock in place. Just a U shaped bolt through the bottom piece. This worked like a charm. I bought a cheap racheting box end wrench from Harbor Freight which worked just fine. A socket wouldn't work because the all thread sticks out as it compresses, and I didn't want to keep moving a regular box or open end wrench.

There was a big black chunk of goo around the center shaft. It was stuck to teh center shaft and drags as the shaft goes into the damper. I will clean that as much as possible. It looks like the damper is pressed in, so there's no taking it apart. I assume the black goo was my bumper that has been dissolved by the oil. Definitely oil, not tranny fluid. I see that Joel replaced this in his. I don't understand how you did that. Did anybody else replace their bumper? I wouldn't know what to use that wouldn't just dissolve also. Is it a big deal if I leave that out? Nobody lists that as a replacement part that I've found.

My Progressive springs and seals are supposed to arrive tomorrow. Come on UPS! Then I will get this one back together and start on the other side.

Thanks,

Dennis
 
Dennis, I used some nylon bushings I have in my toolbox for the "bumpers". The one's I used are actually shifter grommets for older Cadillacs...they stand up pretty well for that, so I figured, what the heck?

Glad you were able to engineer a tool to do the shocks! :clapping: Watch out for that black "goo"...that stuff sticks to everything, and is a pita to get off/clean!
 
I second that, would love to see a pic. will help me when I build one to do the same job.
with me and the wife on the "plus" side, the progressive springs sound like the trick.

think this will be a winter or early spring job.

LOL
 
OK, here are some pictures. It worked pretty well. It would probably work with 2 just as well. Most of the time I was just tightening the opposite sides and then finger tightening the other two. I wasn't sure if just 2 would have been strong enough.






The opening at the top on mine was right at 2 1/8", but that was a bit too tight. When I wen tto pry the top cap off the shock it took some of the plywood with it. 2 3/16" should be just about right. It would also be a good idea to round out the opening a little bit. When I took the cap off, there wasn't anything holding the shock air box in the clamp, since the hole was smaller than the top fo the air box. Maybe if it was just a little bigger it would center it. I may put a slight bevel on this before I put it back together. I will need to compress the springs before I can put the cap back on, and it needs to stay centered or I won't be able to put the top back into the hole at the top of the air box.

I also made some headway into finding a "shock bottom out bumper". I did some research as to what type of rubber to use. Neoprene and natural rubber will disolve in ATF. On eof the types that is supposed to be good for ATF and brake fluid an dfuel is somethign called Buna-N or Nitrile. In my search I found this.

https://www.polyperformance.com/shop/Fox-Shock-Bottom-Out-Bumper-p-834.html

I will probably go ahead and order 2 or 4 of these on Friday (payday). It looks like just what I was looking for?

Dennis
 
Sweet rig!! :good: That's the way to "fabricate"!! :clapping: :clapping:

Not sure if those bumpers will work or not. They may be to large. You can certainly grind the outer diameter down, but I wonder what size the actual hole in them is? Of course, I have no idea how tall the originals are either. The grommet I used is about 3/8" thick, and fit the shock shaft nice and snug. Seems like if the bumper is too thick, the shocks will "bottom" sooner than normal, but it wouldn't be as harsh! :headscratch:
Good luck with the rebuild. I'm betting you'll love the new ride!!
 
The center of the bumper is 0.625" or 5/8". I think that's a little too big. So it will probably sit at the bottom, unless I glue it up top with soem gasket cement or something. I don't think it really matters where it sits as long as it can move when the damper moves it. I bought 4 of them because I was pretty sure the original bumper was pretty thick. I will be searching the websites for a picture of the shock with the bumpers intact. They should be here Monday and I will be on vacation all next week. So it will be a week or so before I can get this thing back together. It will give me a chance to make the improvements to my shock press. I'm anxious to ride it!

Take care,

Dennis
 
I finally got my shocks done! I went on vacation, then when I got back we had a couple fo busy weekends. This last Saturday I finally got back on it. Everything went fine, except I had to modify the wooden tool I made. The end that you put the top of the shock into needs to eoither be big enough to allow the top of the shock to come through it, or in my case I made a little square spot for it to ass through. It's larger on the side where the air fill hose goes into it, so you need to make sure that will allow the top to pass through when you screw it back on.

The second shock looked about the same as the first. It had the rubber bump stop disolved into the oil. It went a lot faster than the first one, except I had to blow the guide bushing for the shock out twice. After I relieved the pressure on the shock with the new springs inside I could get the guide bushin gto drop out. I tapped it on the bench a bunch of times and it wouldnt make it past the lip of the outer shock housing. So I got the air compressor out and blew it out just like I did the seal in the first place. I had to put the wire clip in first. Then I put the guide back in and relaized I had forgotten to put the ATF in the shock. So I had to blow it out again.

I discovered that if you hold the shock upside down and shake it up and down vigorously that you can pretty easily get all the oil out of the shock. If you just tip it over, a little will drain out, but once the it builds up a vacum it stop flowing. By shaking it you get the air and oil to keep taking turns and in a few minutes the oil was almost all out an dit wasn't too messy when I blew it out.

I forgot to use the Locktite on the threads of the shock on the first one. I hope it's OK.

The only other problem I had was when I tried to thread the top on the the shock shaft. I guess there was thread lock left from the first time. I had a hard time unscrewing it, but I just used a wrench on the locking not and it held the shaft. However when I tried to screw it back on it got hard to turn an dit just turned the shock shaft. Hodling the locknut didn't help because it would just unscrew up the shaft. I ended up using a pliers to hold the shaft. I figured that was up where my bump stop was anyway. I did use the Locktite this time, but this one probably didn't even need it.

The bump stops will probably be OK. The holes were a little too large so it just slid down the shaft. So as the shocj goes up and down it will rub against the bump stop. I firgured it would be OK, since there isn't any pressure on it, and it will be immersed in ATF the whole time, so there shouldn't be much friction.

It was too late last night when I finished so I didn't test ride it yet. I will do that tonight. It seems to move a lot easier than before. I think that disolved rubber was gumming up the shock shaft. I put 30 psi in there and it seems to stay put, but I will check it tonight before I ride to make sure it is holding it.

Thanks for the help all,

Dennis
 
:clapping: :builder: :clapping:
Good Deal, Denny!!!
I'll bet you wind up letting some of that air out after you ride it a while...it maybe a little stiff/harsh now that everything is in working order again. I run about 10-12 psi in mine, and it rides just great, but it still doesn't bottom out, even on the BIG bumps/dips.
Glad ya got it done!!! :clapping: :good:
 
Well I finally took the bike out for a short ride with my wife. I am very happy to report that the Progressive Kit has cured the bottoming out problem. We went over some really bad bumps, pwrse than the ones that it was bottoming on last time, and I don't think it ever bottomed out. It felt OK too, not really stiff or anything. It rides liek you expect it to, and I really didn't have to worry about it. I think in the spring I will do the same for the front fork springs. They don't bottom out, but I think they aren't as free as they should be.

Another satisfied Progressive Suspension customer.

Take care all,

Dennis
 
I have been reading all these posts.....and as always some of this seems to be over my head. :swoon: ......the front of my Wing when I stop at a light, kinda stays down, till I start to pull out , and then it will raise ..... I bet mine needs ATF in the Forks. . . . from what I have read a 1980 should have 7.4 oz. of ATF in each side . . . but my question is ... are the Progressive springs 1 spring ( Inside ) another .... or is it a spring that kinda looks like it has been streched on the end ??? and did any Wings come out with Progressive springs factory ??? or was they all special orders... and , is there anyway to tell if a bike has them without taking them out and looking at them ????
 
The rear springs are two springs, one inside the other. The stock spring and the Progressive springs were both built that way. The progressive springs were just a little thicker, and they did get closer together at one end.

My front forks act the same way as what you describe, but maybe that is just how they are?

Progressive is a brand name, not a descripton of how the springs behave, but they were clever with picking the name, because they do behave that way.

If they replaced the entire shock/spring assembly then it would look different from the outside. If they bottom out on you, then I doubt that they are Progressive Suspension replacements. I've never heard anyway say the Progressive Springs still bottom out.
 
There's no way to tell for sure if the fronts are Progressive's springs without taking the caps off.
Stock are 2 springs, Progressives are one long spring tighter wound at the one end.

Do you run any air in the front's? Try 15 lbs or so. That might make them return to top after a stop.
If not you could try new 20 wt fork oil. If still a problem then the springs are just tired.
 
yes I have put Air in my Front Forks..... but.......didn't really change anything.....BUT , I have never checked to see how much Oil is in them.... But, I will very soon. . . Thanks for the answers.
 
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