Side to side play in swing arm 81 KZ305

I took the swing arm off of my bike to check the condition of the bearings and noticed that about 6 or 8 (3 or 4 on each side) paper thin metal washers came out with it. When I put it back together with out them (since they were in pretty bad shape) there is almost 2mm of side to side play in the swing arm. I checked the parts breakdown for that bike and it doesn't show those washers and all the other parts appear to be there and appear to be in decent shape. It's almost as if the swing arm is the incorrect size but everything appears to be stock. I made sure the bolt was torqued to spec but the play is still there. Does anyone have any experience with this sort of thing or have any suggestions on what may be happening?

If those shims aren't noted in the parts diagram I could only assume someone put them in there to tighten things up a bit. It could be the end caps or other parts were worn and the previous owner didn't want to replace them. Are end caps on the sides of the swingarm? I am just guessing because I am not familiar with this bike. In any event it certainly doesn't sound right, but I am sure others will chime in. Do you have a service manual for the bike? I would be surprised if this was some sort of suggested repair to tighten the swing arm up but one never knows. It couldn't have been very easy forcing the shims in place.
Rick H.

Yeah, I'm guessing someone put them there to tighten everything up, it just seemed a little strange to have to do that. There are no end caps. The other style of 305 calls for the end caps which are the same as what is on my kz440 but when I tried to put them on the 305 everything was too wide to fit at that point. I don't have a service manual but I'll look around the interwebs to see if I can find one. Great suggestion!

Here is the KZ305 Service manual: kzrider.com/modules/ServiceManuals/Kawas...0KZ250%20-%20305.pdf

It is often necessary to shim the swing-arm pivot. factory tolerances were poor back then and the easiest way to rectify this was to shim the swingarm. Often these shims do not show up on parts fiches, but the factories were doing it themselves. I have personally found a 2mm difference on KZ650 pivot tubes, one of which was NOS, that needed to be shimmed.

With out the shocks on and the pivot torqued the swing-arm should fall freely with no resistance. Any lateral play or resistance will show up as poor handling. Ideally this is with caps on. It can be a bear to get the swing-arm in there when its setup nice and tight.

On page 153 of the service manual it shows end caps in figure J38 (#7), so I don't understand how your bike would not have them. Ed

Thanks for the info. I guess my next step is to look for some shims!

650ed, it looks like the one they are showing in that pic is a different swing arm/model than what I have. Mine doesn't have the grease fitting or the end caps.

Well for once in my life I went chasing information on something that I don't own. There clearly were 2 types of swing arms made for the KZ305. One had caps on the ends of the swingarm and one did not. They were different but very similar models. The OP has the type with no end caps on the swing arm. Interestingly enough there is almost no information regarding the swing arms in the factory service manual. Nothing is noted about shimming either, not a word. There is something different between the "capped" swing arm and the "non-capped" swing arm as they have different part numbers. My first thought was for the OP to get the end caps and try to install them without the shims and see what the result was, but he claims to have tried to install some end caps from another bike, but he couldn't install the swing arm. My only question in this attempt is what were those caps from and are they the same thickness as the ones in the A2 model? Years ago I had an English bike that required the swing arm be shimmed to fit and it was nothing short of a b***h to get the shims in. They were quite thin and would fold up or wrinkle when trying to put them in. We had to loosen up the engine mounts to get the swing arm in and use a jackscrew arrangement to open up the frame to accept the swing arm. It was an ugly time consuming process and finding the correct shims was next to impossible, but I found some in England. It was a long process to find these as it was before the Internet days. The shims for that bike had to be divided equally between sides too.

Anyway, I would like to know how thick the shim pack was in the OP's bike for starters. At that point one can try to find a solid shim versus multiple shims and make installation much easier. My other thought would be to order one end cap from Partzilla as they claim to have them and see how thick they are see if there is a possibility they will work in the KZ305A1 application. The caps are only 10 bucks apiece so it's not a terrible expense to try one. Granted two end caps should be used but at least having one will give you an idea of their thickness compared to the shim stack that was in the bike. I am pretty surprised there isn't more information in the service manual for the swing arm on this bike. It is almost as if they thought no one would have this bike long enough to worry about wearing out any parts.
Rick H.

Rick,
For the end caps, I looked at the part number that was listed on the parts breakdown for the KZ305 swing arm (the one with end caps) and looked at the part number from the parts break down on the KZ440. Both part numbers were the same. That's not to say that the ones on the KZ440 weren't changed at some point. However, it might be worth the $10 to order one from Partszilla to compare the two to see if they are in fact original. But, unless there is a significant difference in the thickness they will more than likely be too thick to fit inside the frame.
I was surprised by the lack of info on the swing arm in the service manual as well. There was no mention,(that I saw anyway) of any kind of tolerance for side to side movement or what to do if there was. Finding shims seems like it is going to be quite a challenge as well. I haven't dug too deep into yet but the little searching I did yesterday was pretty fruitless. I see that the KZ550 came with shims but I'm not sure if they will be the right fit for my bike. Oh well, I guess this is all part of the fun right? Right, at least that's what I'm going to keep telling myself :laugh:

I guess a lot of what I said you already know so forgive me. I think the "easiest" thing to do is find a cap that will work on each end of the swingarm, but that may not be too easy to figure out. If the cap idea won't work then a single wide shim on each side would be workable instead of trying to stack shims on each side. I am just guessing because I don't have a KZ 305 in front of me. You might want to see what DoctoRot used for shims on the ones he worked on. Is it possible to get a picture of the shims you took out and a total thickness measurement on them? Is each shim the same thickness? I do recall we used a jackscrew on the English bike we had to shim to try and open up the area where the swingarm fit in the frame. Otherwise the shims were damaged when trying to insert them in place. At first the jackscrew didn't do anything but then it dawned on me to loosen the engine mount bolts which gave us the needed flex in the frame to install the swingarm.
Rick H.

P.S. I looked at the shim for the KZ-550 (92025-1228) and the dimension given is 34 mm X .5 mm. Does this sound like it might work in your bike? I am guessing the 34 mm measurement is the O.D. Partzilla doesn't have them, but there are some sources on Ebay. If they are a workable size you might have an option here too.

These are the shims that I took out of the swing arm. There was about 8 of them. I don't remember because there was at least one that was half gone and probably another one that I've since lost. I've ordered some shims from McMaster Carr that should be at the house when I get home. They seem to be very close in size to these and a little thicker so I can hopefully get away with just using one on each side. With any luck this problem will be solved and I can move on the 387 other issues that need to be dealt with. :laugh: