Opinions on swing arm swap?

[Guest]

So I want to ditch the heavy steel swinger on my 79 GS1000 and go with an aluminum swing arm. My question is what would be the best bang for the buck swap? I know the GS1100 swing arm should be a bolt in mod, but was wondering if there is a better option that is not a TON of work too put in. Im very mechanically inclined and have access to lots of machining equipment if need be but i would prefer to do as little as I have to in order to swap swingers. Is anyone replacing the pivot bushings with bearings? Also wondering what size of tire I could stuff in the back without changing sprockets? Thanks in advance for any help!

[steve murdoch]

The GS1100 swingarm is plenty strong enough for even a hot rod GS1000.
Obviously tire size would depend on the wheel you are using. Lots of 160 rubber available for 4.5" Gixxer wheel.

[tkent02]

They already have bearings instead of bushings.

[Crankenstein]

Okay, I just assumed that they had bushings like all the other bikes I've worked on. If I went with a GSXR wheel what all would I need to change, and what year of bike would I need to get parts off of?

[gs11ezrydr]

Stock swingarm

I have a used swing arm approx. 4.5 inches over looks stock on the bike. with new bearings, 150$ arm and 60$ bearings. Bolts right on. Brake arm needs extending is all. Strong, straight and true polished.

[Danb4563]

Gs1100 is an easy swap if you are a machinist. All you need to do is machine new spacers that fit between the bearing and the stock pivot bolt. Pull the spacer from the 1100 swinger and measure the outside diameter, that is the outside diameter you need, then pull the spacer from the stock swinger to get the inside dimension. Make sure the material is case hardened. Once you have new spacers it is a straight bolt on swap using the stock pivot bolt, no frame mods required. I'm not sure about the gsxr wheel though.

[Steve]

So I want to ditch the heavy steel swinger on my 79 GS1000 and go with an aluminum swing arm.

OK, I am just going to ask a question out of pure ignorance here, but "expriing minds want to know".

How much does a "heavy steel swinger" on a '79 GS1000 actually weigh?

How much does an aluminum swing arm weigh?

Yeah, I realize that a bunch of that weight loss will be unsprung weight, but really, you are saving ... what?? about 4 or 5 pounds?

Not trying to knock your project, I just see the question posed rather often and have wondered how much weight is really lost in the process.

.

[Danb4563]

OK, I am just going to ask a question out of pure ignorance here, but "expriing minds want to know".

How much does a "heavy steel swinger" on a '79 GS1000 actually weigh?

How much does an aluminum swing arm weigh?

Yeah, I realize that a bunch of that weight loss will be unsprung weight, but really, you are saving ... what?? about 4 or 5 pounds?

Not trying to knock your project, I just see the question posed rather often and have wondered how much weight is really lost in the process.

.

I did this swap a while back. I never actually scaled the two swingarm a to see the actual difference, but I don't remember it being huge. The aluminum is thicker than the steel. What I can say is, it pushes the rear wheel back a bit. It not enough to be noticeable with the naked eye, but it is enough to require a new chain. It may be that most guys swap the sprockets and chain due to this, and they pick up the weight saving there. It does look nice though.

[posplayr]

If you are so inspired the Bandit 1200 swing arms represent the best(stiffest) upgrade without going exotic. There are also GSXR swingers but (IIRC) I think they generally need to be cut down. The Bandit is narrower than the GS so it needs top hat spacers without any changes to the bearings. You coudl still go mono with either I guess, but the bandit is usually prefered with twin shock for resto-mods.

I'm sure you could do a seach and find plenty. I have on on my bike.

[Big T]

Gs1100 is an easy swap if you are a machinist. All you need to do is machine new spacers that fit between the bearing and the stock pivot bolt. Pull the spacer from the 1100 swinger and measure the outside diameter, that is the outside diameter you need, then pull the spacer from the stock swinger to get the inside dimension. Make sure the material is case hardened. Once you have new spacers it is a straight bolt on swap using the stock pivot bolt, no frame mods required. I'm not sure about the gsxr wheel though.

Actually, it bolts right in with the stock spacers. You'll probably need new spacers, as the old ones take a pounding and get loose. I've done it to both my 1000s. You'll have to machine some spacers/adapters for a GSX or GSXR wheel, as the axle size is smaller. You can go up o 160 width, you'll have to get an offset front sprocket and maybe shave the rear carrier a bit

[chucksuki]

I did the swap 2 years ago and I remember it being a 7lb difference. I did notice a difference personally. plus it looks great

[John Kat]

That's correct it's between 6 and 7 pounds lighter.
Here's mine fitted with GSXR 1100 first gen wheels.

http://www.thegsresources.com/_forum/showthread.php?215140-GS-1000-ST-weight-saving-program&highlight=

[posplayr]

The article say almost 3 lbs that is less than 1.5kg. I suspect the aluminum is stiffer though as it has a larger cross sectional moment of inertia.

[chucksuki]

I saw that in the article too, I actually did a scaled comparison during the swap and it was 7 lbs

[posplayr]

I saw that in the article too, I actually did a scaled comparison during the swap and it was 7 lbs

So it might be a typeo where lbs was substituted for kgs.