using E/E shock mount instead of E/C for 80 GS1100ET any problem?

[don_gibb6512]

I installed a set of Progressive 1202 shocks on my '80 GS1100ET using a 3/8 SS bolt as the bottom mount because the 1202 is Eye/Eye instead of the Eye/Clevis, which is the standard mount for this swingarm. I'm no physics expert but will the force applied to that bolt be any problem for it? This bolt is slightly smaller than the stud mount on the G swingarm. I'm thinking it should be ok but I'd rather have that confirmed with the consensus of this group. For clarity, when the E/C type mount is used the bottom of the shock rests on the top surface of the swingarm instead of hanging off the outer side like the way I installed it.

Thanks.

ps. I'm using an SAE sized bolt because I couldn't find a metric in SS in the size that I needed at the time.

[Billy Ricks]

Shouldn't be any problem. If you want a little extra strength get Grade 8 bolts.

[don_gibb6512]

Shouldn't be any problem. If you want a little extra strength get Grade 8 bolts.

Thanks for the quick reply Billy. Makes me feel more relaxed knowing that I didn't screw up, again. I'll check the grade. They might be 8's. I really didn't want to spend another $250 if I didn't have to, just to get a different type of mount.

[Nessism]

I don't understand how you mounted the shocks. The swingarm is designed to accept a clevis type shock and you are using an eye type shock instead? How is the shock mounted? Did you lay the shock outboard of the swingarm eyelet and run a long bolt through both? A photo would be helpful.

[Billy Ricks]

I don't understand how you mounted the shocks. The swingarm is designed to accept a clevis type shock and you are using an eye type shock instead? How is the shock mounted? Did you lay the shock outboard of the swingarm eyelet and run a long bolt through both? A photo would be helpful.

Sounds like that's what he did. If it were me I'd have tabs welded to the swingarm to allow proper mounting, but he is probably fine as is as long as the offset isn't too great.

[Nessism]

Sounds like that's what he did. If it were me I'd have tabs welded to the swingarm to allow proper mounting, but he is probably fine as is as long as the offset isn't too great.

Too much offset; it will cause a side load on the shocks which will put stress on the shaft and mounting points. Not good.

[don_gibb6512]

Too much offset; it will cause a side load on the shocks which will put stress on the shaft and mounting points. Not good.

Yes, the way it was re-described is exactly what I've done. The point you make about putting too much stress on the shaft and mounting points was why I asked in the first place but it doesn't really make much sense since that's exactly the way it's mounted on the G models. May be that since the G has a steel swingarm and the extra girth of the drive shaft spline makes that a stronger mount? I'd like to know the reason for the clevis mount in the first place. I've never seen the OEM pipes but I'm thinking one of the reasons was for clearance and that this was a more practical way to mount the bottom of the shock to this particular swingarm. I'm not fully convinced that it would be for any excess stresses induced on any of the components involved. It is obviously a stronger mount using a clevis in this case but the fact is I don't have that type of shock to install right now and I've already ridden it with these shocks mounted without any adverse effects that I can tell. But if there are any long term stresses involved that would create a hazard, I would definitely want to avoid that. I may buy a new set of shocks in the Spring, if nothing else just for peace of mind.

Thanks for the input.

[don_gibb6512]

How is the shock mounted? Did you lay the shock outboard of the swingarm eyelet and run a long bolt through both?

This is exactly what I've done. I'll try to get a photo posted but I think you guys get the picture. As far as an offset goes, the shocks mounted almost perfectly vertical, better actually than they did on my G, so I'm not worried about any off angle forces because of that.

[Nessism]

Problem with mounting the shocks as you did is that the lower mount is outboard of where it is supposed to be thus the shock will not be laying in the same plane as origional. In effect, the lower mount is moved away from the center line of the bike, and where the shocks should mount. The shocks are now forced to work through an angle and the shaft will experience more of a side load. The mounting eyelets in the shocks will also experience more of a load since they will not be in plane with each other.

Hope this is clear.

[chef1366]

I'd like to see a pic also. You're saying the shock is at an angle going outside the clevis mount? How did you get the shock to angle? You didn't install the bushings in the upper eye??
Sounds more like a strut now than a shock.

[don_gibb6512]

Nessism, yes it is clear and thank you. Chef, no the shock is not mounted at an angle. It is almost perfectly vertical to the top mount point and is mounted flush with the outside edge of the bushing where the clevis would go over. This is the Progressive 12-1202B shock and the bottom eye is offset from the top eye so as to fit the G and GL models. I will try to get a picture tomorrow and get it posted. Thanks for all the input.

[don_gibb6512]

pics of the shock and bottom mount

http://i241.photobucket.com/albums/ff312/GSgibb/LSShockfull.jpg

http://i241.photobucket.com/albums/ff312/GSgibb/LSShockbottommountclose.jpg

That should make it clear what I've done. I've ridden it a couple more times since I posted last, at a pretty good pace too and I haven't noticed any adverse effects.

[Nessism]

Hey Don,

Your photos show that the lower shock mount is about ½” outboard of where it was before – which might cause the shock to wear out faster since there will be a side load on the shaft. Of more importance though is the integrity of the lower mount strength. The lower bolt is under a lot of stress since it has to be almost twice as long as stock and is cantilevered with the shock loads feeding in from one side. If you decide to keep these shocks, I strongly suggest you use a high grade bolt, along with a locking nut of some sort. The bolt should fit tightly in both the swingarm anchor hole and the shock eyelet – slop will cause impact loads to feed into the bolt. Check the bolt for tightness on a regular basis also.

I know I’m being kind of a weenie on this point but safety is nothing to take lightly.

[don_gibb6512]

"If you decide to keep these shocks, I strongly suggest you use a high grade bolt, along with a locking nut of some sort. The bolt should fit tightly in both the swingarm anchor hole and the shock eyelet – slop will cause impact loads to feed into the bolt. Check the bolt for tightness on a regular basis also."


I have used a high grade SS bolt and locking nut, along with plenty of LockTite. I used a bolt size that fit snug in the bushing, hoping to reduce any wear on the bushing itself. I will be checking for tightness regularly.

"I know I’m being kind of a weenie on this point but safety is nothing to take lightly."

Not at all and I thank you for your input. This is exactly why I posted here in the first place. I'm all for safety first, especially mechanically. I'm the first to admit that I'm no expert mechanic and if anything can go wrong, I'm sure to be the one to do it that way. I doubt I'm keeping these shocks in the long term. I'll probably buy the 12-1204B set from Progressive in the Spring but I just wanted to be able to get by with these until I get some other issues worked out with this bike. I keep dumping $$$ in to it and I want to be completely sure it's going to pay off.

Thanks again.

[chef1366]

I wouldn't run the bike like that. All the weight of the bike is on the bolt alone. Buy the right shocks. IMHO.
I'm not trying to argue or start an argument. I am just thinking about your safety.