81 750ltd swingarm swap advice needed

I got a '93 ZX7 swingarm a couple of month ago to swap into my 81 750LTD, well I finally decided to do, it was too much fun riding... and I was working on my other project, a naked 83 GL1100 Goldwing

Anyways I was thinking about drilling out the holes for the pivot bolt, but I don't think I could drill them straight and would most likely mess things up.

So I was reading in older posts how some got a sleave made to use the KZ bolt in the new swingarm, I think this is how I want to go about it. What would be a fair pricerange to have a sleave made and what material should be used ?

And I want to keep the dualshock setup what would be a fair pricerange to have the shockmounts made and welded onto the swingarm ?

I already checked to make sure the chain will clear the frame and I know I'll need an offset 530 sprocket/chain.

Anything else I'm not thinking of?

Thanks for any advice.

Link to project Link: Link

Can't give you exact numbers, but if you go to a machine shop and ask them to make you the appropriate sleeve, It will probably cost you $100-$150.
Since the bearings ride on the sleeve, it probably should be hardened, I think case hardening will probably work, since you just need the surface hardened where the bearings ride.

The diameter of your original pivot bolt is 16mm. what diameter is the new one?

I'm putting a GPz750 swingarm on my 80 KZ750E, and the KZ750E has a 16mm pivot bolt also, while the GPz750 has a 17mm pivot bolt. I have a 17mm drill, and although we used it on GPzInfested's KZ650/GPz750 swingarm, I don't like the results so I'm not doing mine that way.

I'm making a boring bar that uses HSS cutting bits that will be 16mm on the end (to fit in stock size and be a guide) and then stepping it up to 17mm, so that part will act as a guide after the hole has been enlarged. The boring bar will be 1/2" on one end to fit in a 1/2" drill motor.
Since I have to widen the frame about 1/8" between the pivot bolt holes, I am also putting another place for a bit on the 17mm section to act as a facing cutter to cut the face of the bolt holes 1/16" on each side.

It's harder to make it and describe it than it is to use it, and It's really a limited use tool (not a big call for it).

I was in the shop till 3 am this morning working on it, turning a hot rolled steel bar down to .667 and .627 22" long between centers is virtually impossible without a follower rest, or at least a steady rest, and I have neither. And turning hot rolled steel really sucks, that stuff is nasty to work with, I'm thinking about looking for a piece of cold rolled round bar, maybe 1018.

The pivot bolt is quite large with a 25mm diameter, it's hollow... and the inside it too large 18mm or I might have been able to use the bolt as a sleeve... would have been to o easy.. :laugh:

Yeah boring bar makes sense, sure is nice to have the tools to make one, and the skills.

With a 100 to 150 bucks the sleeve would be the second most expensive item I bought for the bike :woohoo: , guess I'll have to fork over the cash, at least the swingarm was only $10.

Edit: I was just googling 18mm outside and 16mm inside diameter and got a result that says 1/2 inch waterpipe has actually these dimensions :huh: ?? Is this something I could work with?

I had my local welding/machine shop make my sleeve. I gave them the stock swingarm bolt and the swingarm. I simply told them to make a sleeve that will fit nicely into the swingarm, with a hole hollowed out down the middle that will tightly fit this swingarm bolt. Cost me exactly $98. I was very satisfied with the outcome, and it worked great.

KZPens wrote:

The pivot bolt is quite large with a 25mm diameter, it's hollow... and the inside it too large 18mm or I might have been able to use the bolt as a sleeve... would have been to o easy.. :laugh:


Edit: I was just googling 18mm outside and 16mm inside diameter and got a result that says 1/2 inch waterpipe has actually these dimensions :huh: ?? Is this something I could work with?

Using your existing 25mm pivot bolt as a sleeve may work. I would make 2 short sleeves instead of making one long one, using the 18mm OD and 16mm id. Then cut the 25mm pivot bolt to the same length as the width of the new swing arm and and slide the sleeves in each end and have them welded in.

As for the water pipe, if it is precision tubing with 18mm OD and 1mm wall it may work if it is a material durable enough.

I'll drop by the hardware store in the afternoon and see what they have and how tight a fit it would be. If not a $100 doesn't sound too bad, then again I bought my other projectbike for that much.. :S

Thanks all.

I don't know what you mean by "water pipe", but if it's the iron pipe it's galvanized and has a wall thickness of 1/8" (little over 3mm).
Galvanized means it's zinc plated, and you don't want needle bearings riding on zinc plating, the zinc will flake off and destroy your bearings in a short time. Standard 1/2" iron water pipe is supposed to be approximately 12.5mm ID and 19mm OD. And after having just cut and threaded a bunch of 1", 3/4", and 1/2", iron pipe for the air lines in my shop (overkill, but it was free), I can assure you that the wall thickness is much more than 1mm