The Big Sue resto-mod thread

MaxPete

Lucille, Betty, Demi, Gretel & Big Sue money pits.
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Howdy all!

I know it's not an XS650 but I do like this group of folks so I am going to share the story of my resto-mod resurrection of my "new" 1979 GS850G with you.

The Suzuki GS-Series of Four-Stroke Bikes
The GS850G was the fourth in the early four-stroke GS-series bikes from Suzuki. These were all eight-valve engines and most were chain-driven. The first GS models were the GS750 and the GS400 which were introduced in 1977 as plain-jane wire-spoked bikes. The GS400 was a twin and a direct competitor to the Honda CB400T Hawk and the two similar bikes from Kawasaki (KZ400) and Yamaha (XS400). I'd guess the twin-cylinder end of the market is a pretty tough place to make money as there were a lot of bikes and the people who bought them were extremely cost-conscious being teeny-boppers, students, and el-cheapo commuters. The Suzuki 400 was eventually bored out to a 425 and then a 450 - as were several of the others. The companies used them to attract new riders to their part of the market in the hopes of selling them something more substantial.

The four-cylinder GS750 was an entirely different class of bike however and of the 750-900cc models on offer from the J-4 in the mid-late '70s, the Suzuki was generally agreed to be the best handling and one of the nicest to ride with a good seat, decent ergonomics and a very reliable and very strong engine that used a roller bearing crank (unlike the Honda CB750) and plain cam-bearings. The roller bearing was likely a hold-over from the two-stroke days of Suzuki and I'd guess they were going for supreme reliability after the RE5 Wankel engine debacle which nearly killed the company.

The GS750 frame was particularly sturdy and all of the GS bikes were known as very steady handlers and usually won "Best in Class" from the big magazines. The smaller GS550 and the one-litre GS1000 were added as 1978 models and made hits in their segments as well. Later, each size became available as a pseudo-cruiser. Suzuki called them "L" models which stood for some sort of marketing sh!t like "Low Slinger" or something like that and they had longer fork tubes with leading axles, buckhorn bars and two-level "king-queen" seats, as were found on the contemporary Yamaha "Specials".

The GS850G - Shaft-Drive Bike....ahhhhhhhh:heart:
In 1979, Suzuki did something a little unique when they went to the parts bin and developed a very nicely engineered shaft drive system which led to the GS850G (the last "G" indicated a shaft-driven model). I think I read at the time that the GS850G used the GS750 crankshaft with a GS1000 cylinder barrel and top end - but that may not be correct at all.

The basic layout is very similar to the XS750 triple which spawned the XS850 and the mighty four-cylinder XS11 / XS1100. I really wanted a shaft-drive bike and looked long and hard at the XS750 when I was shopping in 1980, but the first reports of transmission problems were starting to emerge on the XS750 and so I steered toward the Suzuki.

The '79 GS850G had a points ignition and a kick-starter (both were omitted on the 1980 models) as well as the usual Suzuki gear indicator (very handy on a smooth bike) and a pretty accurate fuel gauge. It also had a really good self-cancelling turn signal system that worked flawlessly (in my experience) and they introduced an even better seat with two grades of foam. All of the testers lauded the GS850G (in particular the "standard" model with its long, broad flat seat) - as having one of the best seats in motorcycling and I can certainly agree with that. It was MUCH more comfortable than anything on any other brand that most magazines tested and believe me, I read them all very carefully before choosing a snazzy red 1979 GS850G as my very first brand-new vehicle.

In the late autumn of 1980, I was in the 4th and final year of my mechanical engineering degree and I had already nailed down a job in the oil field working for Schlumberger Wireline Services in Paris France. Thus, I knew that I was about to experience a major upswing in economic status so I traded in my treasured 1975 XS650B on a left-over, but brand-new 1979 Suzuki GS850G and was the proudest kid in town on that big red machine.

I rode that bike all over North America for more than 12 years and it never gave me one single mechanical or electrical problem in more than 100,000 km (about 62,000 miles). All I ever did was change the tires and early on, each valve needed a shim - once - but not after that. Oh - and I changed the brake pads at about 85,000 km, a few light bulbs, and the battery a couple of times. As I said, the gear indicator, fuel gauge and self-cancelling turn signal systems never missed a beat the whole time.
1979_GS850G_Day-One.JPG


Suzuki built several shaft-drive GS models - the 850cc variant that I had, a very nice GS650G (@Skull has one of these - lucky dog), a big-bore GS1000G and a later GS1100G - both of which usually came as full-dressers with Suzuki-branded Vetter fairings and bags. The 850 was generally felt to be a tad heavy at a little over 600 lbs (about 275 kg) but they handled very well and were steady at high speeds. The performance and durability of the Suzuki engines and driveline were impeccable and while they weren't the most powerful bikes in their class, the people who had them really liked them (I sure did).

I drilled the discs and eventually put a colour-matched Hannigan Sport Tourer fairing on her and we went everywhere - 500-1000 mile days were done without hesitation and in complete comfort. I think I was one of the first people in my town to use a tank bag, although I had to make the harness myself and have it sewn at a tack shop - where you get horse riding stuff. A set of cheap saddlebags and an audio system I rigged up with a Sony Walkman tape player (in the "mickey pocket" of my leather jacket) and a set of earphones built into my black Simpson "Darth Vader" helmet - and I was a sport-touring machine.
17. Peter at cottage with the bike - Suzuki 850 - Aug. 1982.JPG


In the winter of 1990-91, I came to feel that my riding days were over (kids, education, mortgage, etc.) and so I stupidly sold the GS850G for not much money (DUMB DUMB DUMB) and got out of bikes for about 25 years....until the bug bit again in 2015.

My "New" 1979 GS850G
Forum member and my good friend @lakeview was on the hunt for another XS650 and he found one in the small town of Innerkip near London, ON. During the conversation, the seller mentioned that he also had a 1979 GS850G - and would Lakeview be interested in that bike as well? My buddy recalled that I liked GS850Gs and so while it not would be a bike for him, he pointed me at it....and.....wah-lah!

This GS850G is black (or it is now...) and it is only a few serial numbers different from my first one bought back in 1980. They likely were shipmates coming over from Japan in 1979. When we buy a used vehicle in Ontario, we get a complete read-out on the ownership history of it. My first bike went to Tony's Cycle in Kingston, ON where I went to school and this new one was initially sold in London, ON near where I live now.

I met @lakeview at the P/O's home and bought the bike - and Lakeview brought it home for me in his big blue GMC Savanna van. The photos below were taken on Saturday morning when @lakeview and @totalfool came down in the van to drop off the bike - which I call Big Sue.

The new 850 doesn't run at present as the P/O had removed the coils to test them before he stopped riding it around 20 years ago. He told me that the bike was becoming hard to start - but I'd guess that the carbs needed to be cleaned or the points may be out of whack. I am not concerned and will nail it all down and get her going again. The folks on the GS Resources.com web forum tell me that the valve clearances tend to close up a little over time and so I will check all of that before I start the bike. The valve adjustments are shim-on-bucket type but new shims are still available ($5.25 USD each) and since they are hardened right through, you can adjust their size on a surface grinder without causing any harm.

The engine is free, her old tires hold air and the brakes even work...a little. She is complete and pretty much undamaged, but as noted earlier, the paint is badly faded and there is a small dent in the tank just under the "K" in Suzuki on the left side.

Anyhow, here she is....

1979 GS850G - Black-03.jpg

1979 GS850G - Black-04.jpg

1979 GS850G - Black-05.jpg


The nice looking Suzuki dashpad is missing and the front turn signals and chrome Suzuki fork badge under the headlight have been muntered (the bike came with an el-cheapo Vetter WIndjammer knock-off and some hideous fibreglas saddlebags (free to a good home!!) but otherwise, she's all there.
1979 GS850G - Black-06.jpg
 
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Good start, does look complete. I took on this GS a few years back. Not the easiest to restore as some engine parts were impossible to find. Mine was the GL model so I got rid of the hump seat and pull back bars. You mentioned that the shims can be ground on a surface grinder. That is normally not a good idea, and most builder frown on that, your better off buying the correct shim.
This bike will be sold this year. It has a Wisco 1134 kit because you cannot buy oversize pistons for it, NLA
hagerty photo.jpeg
 
Future Plans for Big Sue
I am not in any hurry on this project as I am still working full-time (dumb) and I have two other bikes in line before this one (the two XS650s - Demi and the re-do of the dreaded Lucille :yikes: ) - but I hope that my employment status changes soon and I can get back to what I want to do every day.

On Big Sue, I want to go over everything on the bike before starting it and, given the slightly dodgy reputation of late 1970s Suzuki electrical systems, I will power it up very carefully. I will pull off the clutch cover and check in there, remove the valve cover and check all the clearances, change the oil and read-end lube etc., and put a new battery and tires on her. Depending on the condition of the engine I may install new rings and gaskets up top - but with only 54,700 km on her - I doubt this is necessary.

The hard starting reported by the P/O is likely a carb issue - as the bike was more than 20 years old when he last rode it and so I will go over the Mikunis carefully as well. The inside of the tank is pretty clean but I will likely tumble it, have the dent fixed, and then have it painted. I have already priced a stripe kit (available from Diablo Cycle in London, ON) and I will scrounge anything else I need on the GS Resources forum and the web. As always, Partzilla has all the parts fiches and a good deal of stuff is still available plus I am pretty good at searching for OEM parts on the web.

Cheers,

Pete

Stay tuned for more - watch this space!
 
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Check you drive splines, View attachment 262172 hope they dont look like mine did

YIKES! I haven't checked anything yet - except that the engine is free.

On the matter of grinding shims - there is a bit of a debate on the GS Resources forum about that. One guy says that since they are through-hardened, it should be OK to grind them as long as the surface finish is good (or at least, as good as a new shim) while others say that it is a baaaaad thing to do.

Frankly, for $5.25 / shim, I will just buy new ones. A whole set would only cost about $42.00.

P
 
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I'm sure you already know, but even if the reg/rec is fine and/or you're wanting to keep it in Concourse condition, switch that rascal out for a unit from a Honda CB250N. I don't know of a single GS back in England that hasn't had this done. When i worked in the shop back there (shit, 30 years ago!) we always changed them out for the Honda part. I don't recall the wiring sequence off the top of my head (30yrs.......) but I'm sure it's Googleable. It solved a ton of potential future starting, running & charging issues & protects the rotor & stator from cooking.

FYI, the 850 shares pretty much everything from the case mouths up with the 750. The liners are different (obviously) but pressed into the same block body & the head is the same as the Thou. Also also, if you want a performance kick (😉) GSXR1100G flatside carbs will fit if you remove the airbox. That REALLY wakes the old girl up! 😁

My avatar pic is my old 750, with an 850 cylinder block installed, along with a very well ported 750 head. Silly high compression pistons to match the smaller combustion chamber top & carbs from a GS1100 (I couldn't afford Gixer numbers back then!)
 
I'm sure you already know, but even if the reg/rec is fine and/or you're wanting to keep it in Concourse condition, switch that rascal out for a unit from a Honda CB250N. I don't know of a single GS back in England that hasn't had this done. When i worked in the shop back there (shit, 30 years ago!) we always changed them out for the Honda part. I don't recall the wiring sequence off the top of my head (30yrs.......) but I'm sure it's Googleable. It solved a ton of potential future starting, running & charging issues & protects the rotor & stator from cooking.


Pete, if that's an excited field alternator (NOT PMA), the homemade ones it TECH will likely work just fine. Upgrading it to an automotive duty system would cut off any problems before they pop their ugly little heads up.
 
Pete, if that's an excited field alternator (NOT PMA), the homemade ones it TECH will likely work just fine. Upgrading it to an automotive duty system would cut off any problems before they pop their ugly little heads up.
It's PMA - even worse, it's a miserable 12-pole PMA on the 79. Barely enough to keep 'er lit.
A Shindengen SH-775 is the recommended one for these oldies. Sure, there are later ones that can handle higher loads, but no point in that.
The aforementioned Honda reg-rec was a fairly useful fix for a few years, but even they don't cure the problem, merely postpone it.
 
I talked to the shop about shims for a Honda and the shop had a leave the old shim with some cash get the replacement
Policy
I did not change it since it was a big job and had tight OK clearances I believed they got tighter with wear but don't know

Is not 54 000 Km on the high ( danger ) side ? depending on Maintenance or am i Wrong again ?
With oil changes and warm up one thing -- But not all back then did that
Lets se what happens.
 
Great looking project @MaxPete , can wait to see your progress on this one. On my Supra, the valve train runs on shims too. Within our community, we try to swap shims for the proper thicknesses. We tried to establish a central bank of shims where people could swap them one for one but the idea didnt work out. Congrats on the new ride!

@cra-z1 , that’s an awesome looking Suzuki you have there. Would love to own something like that.
 
You probably already know but I had a ‘78 XS750 and I loved that shaft drive, still do!
:agree: I enjoyed the shaft drive era as well.
I believe it was the manufacturing expenses that ended the common jap shaft drive and not the performance characteristics criticism.

Go GSPete ! What would be your ideal fairing to find?
 
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