Swingarm swap and cleanup:

[MK3Brent]

So, I decided to clean up the rear of the bike a little.
I would prefer to have some wire-spoke wheels over these, but I will keep these for a little longer.
I swapped the swinger for an 1100E aluminum version.

I stripped and wire-wheel prepped the wheel, and them masked the tires off with index cards.

Comparison to the GS750 swinger on the left, and 1100E on the right.

Every component I took off in the rear I cleaned or re-painted.
I removed the rust from the springs, and re-painted with enamel.
Each bolt I cleaned, and it really shows when you look at the bike... overall I'm pretty happy with it.

 

[hampshirehog]

Looking good. Which way did you go to make the 1100 swinger fit?

 

[MK3Brent]

This one was the exact same, minus the pivot bolt diameter.

I was under the impression they were between 2-3" longer, however this part measures 20.25" center to center.

Unless there's another style, it was the same length as my 750's.

 

[TheCafeKid]

He means what did you do to make the pivot work? You can't put that smaller 750 pivot through that arm, the bearings are too large. It'll be sloppy mess.
I simply drilled out the frame bosses when I did mine.

 

[MK3Brent]

That should be fairly straight forward.
I don't think anyone is dumb enough to put the smaller bolt through the larger bearings.

Use a screw clearance for 5/8" bolt. (Ream to: 0.6562in)
Use a factory pivot bolt for that swing-arm.
I opted for 5/8-11 socket-head cap screw bolt myself.

 

[TheCafeKid]

That should be fairly straight forward.
I don't think anyone is dumb enough to put the smaller bolt through the larger bearings.

Use a screw clearance for 5/8" bolt. (Ream to: 0.6562in)
Use a factory pivot bolt for that swing-arm.
I opted for 5/8-11 socket-head cap screw bolt myself.

You'd be very surprised... Many people with hacksaws shouldnt be allowed to use em.
Those same guys who'd stuff a smaller pivot through large bearings are the same ones who run no front brake on a bike at all, and slap pod filters on their carbs with a pipe and then wonder why it runs like total ass.
"But it looks soooo cool!!"

There are a lot of people out there who have zero business modifying a spoon, let alone a motorcycle. But that never stops em

 

[hampshirehog]

Last time I tried modifying a spoon it turned in to a fork. Ever tried getting soup from the bowl in to your mouth using a fork.....?

Thanks for the measurements, even though I confess to being a metric-only feller when it gets to decimal points of an inch; I'll be able to work it out though.

You did yours with modded bushes didn't you Josh? I can't find the thread, must be searching for the wrong thing.

 

[JEEPRUSTY]

Nice work on the de-lousing and dis-infecting.

I like the paint work.

 

[MK3Brent]

Thank-you.

I gotta do something about the seat...
Perhaps a banana seat off a Huffy or something... I dunno.

 

[T8erbug]

Did you machine your bushings to get that conversion to work? I'm in the process of the exact same swap and do not want to drill the frame out to fit the larger pivot. . I just don't trust I can find a way to bore the hole so that it is truly concentric. SO, any info on how you did your swap would be greatly appreciated. Thanks!

 

[Guest]

He means what did you do to make the pivot work? You can't put that smaller 750 pivot through that arm, the bearings are too large. It'll be sloppy mess.
I simply drilled out the frame bosses when I did mine.

I tried that as well (drilling them out, oh god what a mistake) on my my 750E to 1100E swing arm conversion. Turned into a bloody mess it did. Had to cut out the frame swing arm bushings, had two new bushings made and welded them in. The next problem was the 1100E bolt is 1 1/4 too short (that was because of the foot peg mounts are different between the 750 and 1100). So had a new new made. Though from your pic you didn't seem have that same problem since you didn't use the stock foot peg mount. Now it's all together and looks great. Here is a pic of it with the wheel mounted.

 

[Guest]

Here is pic of it installed.

 

[MK3Brent]

Did you machine your bushings to get that conversion to work? I'm in the process of the exact same swap and do not want to drill the frame out to fit the larger pivot. . I just don't trust I can find a way to bore the hole so that it is truly concentric. SO, any info on how you did your swap would be greatly appreciated. Thanks!

No, just drill and ream.
Fits fine, works fine.

Just size everything correctly.

 

[Chuck78]

750 vs 1100 swing arm length

750 vs 1100 swing arm length

See my attached thumbnail pic, My 77 GS750 measures 18-1/2" from center of the pivot to the very front of the axle slot, and the GS1100 swinger I have to install on it is DEFINITELY much longer, see pic. With the axle slammed all the way forward, the 77 GS750 swinger is about 1-1/8" or 1-3/16" shorter than the 1100 swing arm. Not sure what year 1100 it was off of. I am thinking that maybe the newer 16 valve 750's also had a longer wheelbase?
The photo posted with the tape measure looks confusing, like the tape measure is coming from the front of the bike but indicating the stated measurement center to center of the swing arm.

This one was the exact same, minus the pivot bolt diameter.

I was under the impression they were between 2-3" longer, however this part measures 20.25" center to center.

Unless there's another style, it was the same length as my 750's.

 

[MK3Brent]

The dimension above is center to center.

From the rear axle center +/- .50" to the pivot bolt center.

 

[Guest]

Aaah one thing I forgot to mention, since the 1100 swing arm uses larger bearings, the front part of the swing arm is going to sit a lot closer to the back of your motor. When I saw it, I just said to myself, wow that is close lol. I had to route my drain hose from the air box around the swing arm rather then in between the swing arm and engine case. The 80-81 GS750E and 1100E have the same wheel base, and yes it is a bit longer then the 77 models.

 

[MK3Brent]

Aaah one thing I forgot to mention, since the 1100 swing arm uses larger bearings, the front part of the swing arm is going to sit a lot closer to the back of your motor. When I saw it, I just said to myself, wow that is close lol. I had to route my drain hose from the air box around the swing arm rather then in between the swing arm and engine case. The 80-81 GS750E and 1100E have the same wheel base, and yes it is a bit longer then the 77 models.

It is close, 1/32" clearance.

Good thing that part doesn't shift.

 

[Guest]

It is close, 1/32" clearance.

Good thing that part doesn't shift.

For sure...

 

[allojohn]

See my attached thumbnail pic, My 77 GS750 measures 18-1/2" from center of the pivot to the very front of the axle slot, and the GS1100 swinger I have to install on it is DEFINITELY much longer, see pic.

Yep, so you'll need a longer chain. I did the '82 1100E swing arm and 530 conversion - forgot to take that onto account. Doh!

 

[MK3Brent]

Must be a difference in the years.

My bike is an 82'.

Was kind of a surprise it was a direct swap, minus the pivot bolt.

I had new chain/sprockets ready to go.