BretIPC

Thank you for all this information. I have basically all my stuff ordered, and confident that most of it will work. I went with Wiseco 73.5mm pistons for the GS1000. Only 1.5mm oversized, but was all I could really find for a 2 valve piston. I did look briefly at some of the Kawasaki stuff, and I don't remember at this moment if there was more options there. I know this was a safe bet. The compression will be higher so that will help and the customer was happy with it. I went with Kibblewhite valve train parts. All were for the GS1000 as the OEM part numbers were all the same to the 1100. Kibblewhite had all the lifter conversion parts, springs and guides. Not 100% sure if their guides are shorter than stock, but from my experience their stuff usually is. I can modify if needed. They didn't have a listing for the valves though. I went with Kawasaki Model J valves as they seem to be pretty much identical and their tech was pretty confident they would work. I believe the intake 0.5mm bigger than the GS. I would have liked to go +1mm on both valves, but the customer didn't really want to get into custom stuff. I will be doing some minor porting work along with that. Once I figured out the 1000 and 1100 have the same exact cams, that was a pretty easy pick. I sent them out to Web Camshafts to be hard welded and ground. I was able to get APE stuff kits and some other upgrade parts from them including clutch pack. I didn't upgrade the basket.l though. I don't have the carbs. The customer just dropped me off the long block. He is sending me the new intake boots he got so I can see how they line up with the intake ports and make changes if needed when porting.

I talked to LA Sleeve directly. They used to make sleeves for this engine to go bigger than 75mm. They stopped producing them due lack of need in the market. They can still produce them for me if I want to go 76-80mm. I am not going to go that far with it. I am going to stick with boring out the stock cylinders a bit and doing some top end work.

I'm not looking to get into a pissing match here. I wasn't asking for anyone to tell me what parts to buy or how to build the engine. I started with a simple question of what the limit was for the stock cylinders to be bored out to. Then it morphed into where to find parts for this not-so-popular engine. I wasn't looking for advice on how to build it, or what combination of parts to use to get the most power. Sure, I could guess and spend thousands of dollars in parts and hours and hours of time test fitting, modifying, and trying different things. But why not use the resources we have at hand in this modern day and age to make the process faster, easier and cheaper by inquiring with people who already know the answers? Isn't that basically what the service manual is? Someone with more information and more knowledge wrote that so we didn't have to put all the time and trial and error into figuring it all out. Just because forums and the internet weren't an option 35+ years ago, doesn't make it an invalid source of help and information to streamline a process.

Isn't the whole purpose of these forums to share information and help people who may not have as much knowledge as others? I've been building engines my whole life. Everything from single-cylinder bikes to modern sportbikes to V-8s to diesel truck engines. A few months ago, I built a 900cc 3-cyl Can-Am engine that with the right turbo will hold up and put out 450hp (I only built the long block and I don't think he has enough turbo to make that, but it was too much for the stock engine). I have a full cylinder head machine shop and am direct with a lot of big-name manufacturers. To me, an engine is an engine. They all operate on the same principles. Yes, I don't have experience with these old Suzukis, that's why I came here. If it was a 16-valve engine I could go to any of my suppliers and just pick parts directly out of their catalogs and be fine. This one ended up being an oddball and there weren't direct parts listings. Even MTC and Webcams told me that they never heard of an 8-valve GS1100 and they are big names in this industry. I didn't want to just order a bunch of parts, hoping I could make them work then have to deal with returning them, or even worse not be able to return them because the were special ordered or made. I have pretty much figured it all out at this point between the information I learned on here and from talking to Kibblewhite, Webcams, and APE. I took the options that I found available and talked to the owner and decided the route to go. Just have to locate a few small things still to finalize the parts list. Thank you all for your input!

APE doesn't sell the OS cylinder kits for this. They mostly deal with just the 16-valve stuff. I am assuming I can still re-sleeve this one if I want to go bigger. Can anyone confirm that there are sleeves for this that would achieve this? Are the 16-valve engine sleeves compatible with the 8-valve cylinders? I know the p/n of the cylinder assembly is different. Also, does anyone know about options for valves and valvetrainparts? Kibblewhite seems to have everything listed under GS1000 except for the valves. They said I could probably use KZ1000J valves, but they weren't 100% sure. I see APE makes valves for the 8-valve, but they are quite a bit oversized. Is there anything to gain with larger valves with only slightly larger pistons? If not, at what displacement should the valves be oversized? As a disclaimer, this is not my engine. I have a motorcycle shop. I mostly work on dirtbikes and ATVs from within the last 20 years or so. I also specialize in cylinder head machining. I don't turn away from much, but I am not familiar with these older street bikes. The customer brought me the engine and wants to build it to the street/strip bike. I think it was assumed that with the availability of parts listed as GS1100, this would be a simple process with lots of options. Thanks to the help of this forum and also conversations with suppliers I am narrowing it down, but it still isn't simple.

I'm in talks with APE now. They seem to have knowledge and experience with these engines and can supply some of the parts. Still going back and forth with them to see what all the available options are.

Thank you. I reached out to them 4-6 weeks out to get, but available. Does anyone know of a source for valves? I already talked to Web about a cam. I would have to have it welded and custom ground, but again it can be done. I'm sure I could get custom valves made somewhere, but wondering if there is a source for them currently.

Got it

The product you linked to was for a 1000. Will those pistons fit in an 1100? I'm going to head to the garage soon and take a bunch of measurements so I can check and compare things.

2-Valve

I called MTC and they don't make anything for the 2-valve. I also called Webcams about camshafts and they don't make anything. Both of them said they were not aware that a 2-valve GS1100 even existed.

I'll have to give MTC a call. At first glance, it all seems to be for 4-valve

Does anyone know of a good source for pistons for a 2-valve? Alternatively, can a 4-valve head be swapped out?

I am not sure if I was looking at the correct pistons. I just started doing some research and most pistons come up as just GS11000, they don't specify which sub-model. I didn't get as far as measuring the pistons or wrist pins or anything yet. I just started looking around at things. I know the stock size is 72mm, and most of the pistons I see are 74mm and up.

I have been looking for parts for an engine build on. 1982 GS1100G. There are a lot of piston options out there in both size and compression. I am trying to figure out how big can we go on the stock cylinder/sleeve before needing to resleeve. I'm not saying I am going to just hog it out to the max, I just want to know what my limits are so I can weigh the costs of different options. Thank you.