new member from Europe

[Guest]

Hello,
I am from Slovenia. My father used to ride a GS850G, with me on the back. With time he collected a few (I think three) spare engines for it (one is probably a 750), and a GS1000 frame and other parts. I plan on dropping one of the engines in the 1000cc frame (probably the 750 with chain drive, but perhaps fit the 850 top end). I know the old 850 was by no means a light bike, but I would love to achieve this with my build (or, at least as much as possible).
Here's a photo of my father's GS:


This was taken on some island down in Croatia.
It's an early model, kick start, old slide carbs and points ignition. As simple as it gets. This bike always had some electric issues (probably a bad stator), and mainly because of that, it's been staying in the garage for years now. It is fairly original, with the nice small fairing, similar to the one the GS1000S had. I'd rather preserve this one and build up a bike from the spare parts that I have. I had lots of bikes, but out of Suzuki only a few old GS550's and GS500's (basically the same, but the 500 was only made for some European markets for much cheaper registration), three GT550's and currently I also work on a late model GT750. Currently, I have quite a few projects (Moto Guzzi T5, Honda CB450, Ducati Pantah, Moto Morini, BMW GS... never gets boring), so this'll probably still have to wait a bit.


My plan for the bike would be to use the Suzuki frame and engine, but not much else (mainly because I also do not have the correct parts either). I'd fit some Italian suspension (f.e. late model Guzzi cartridge forks with modern bitubo dampers are really good and if I polish them the'd look really classic, and that would allow me to use Brembo calipers and cast steel discs too (in my opinion far better than any old stainless disc). I have a few sets of Marzocchi Strada shocks for the rear, that'd probably also fit and work nicely. For the carbs, I would really prefer to use some slide carbs (I really dislike old Mikuni CV's). Being close to Italy, perhaps I could find a set of Dellortos from old Benelli fours, or just set up four independent ones with four cables (they're all basically the same either way, but if I use four independent ones without a linkage, the throttle becomes really hard to pull - the old Guzzi Le Mans had massive 40mm Dellortos with special mechanisms on top that made the throttle really short, but really hard to pull). I'd also try removing some weight wherever possible, but I know the basic frame and engine are quite heavy to begin with... My 350 Morini has under 150kg, which is wonderful, but if I could get the GS under 200, I would probably be very happy. I do not know quite where to start removing weight. The cast wheels were probably heavy, as well as the forks.


EDIT:
Also, a photo of my fathers GT550. More or less completely original (the engine covers were polished, and we also have the correct handlebar and front mudguard parts now, but this photo is a bit old). Only about 20000km. Quite a monster to ride, it feels like it revs instantly. And you soon figure out the brakes are a joke any way.

[roeme]

Welcome to the forum.

Looking forward to read about your progress. Looks like you already know your way around wrenching on bikes.

It does sound like your father's 850G only needs a new stator, battery, carb cleaning and fluids.

As for the "FrankenSuzi" you're planning to build; it's nice that there are still countries where you can get those road legal...no chance of that here

The cast wheels are heavy, but at the same time, much more rigid - I have no idea if this is noticeable outside of a racing track though.

I think most of the weight on these bikes is in the engine and frame, like you said. Though, if one goes through the whole thing bit by bit, there are quite a few places where a bit of weight can be shaved off by replacing them with alternatives: Airbox, Instrumentation, some electrics, lights, indicators, chainguard, fenders, rear bodywork...

Still, not sure if you can get below 200kg, since the dry weight of a 550 with spoked wheels already clocks in at 195kg.

[GSXR7ED]

Welcome!

Glad you're here and posting beautiful background pictures!


Ed

[pikl]

We still start my fathers 850 every year and go on a short trip to warm it up well. But my father collected bikes for decades, and me as well, for as far as I can remember. However, maintaining them becomes expensive, so we only register a couple.

Yeah, technically, such things should not be legal here either. But the frame I have is not listed in any record (I've checked). In my country, that means I can get papers for a "lost historic vehicle without any owner". Even if all the parts are not original, the "homologation" has to be made for the whole bike (the approval that it can be used on the road). They take photos of the bike, and in this case, they may write into the homologation something like "restorated/rebuilt with non-original parts that are road legal". Once I have that paper, with the photos of the bike as it is, it is completely legal. But the persons who inspect the bike and take the photos for the papers will of course not allow just anything on the road (needs to look proper, not just something thrown together). I've registered a few bikes this way (although I prefer to keep my bikes more or less completely stock, so that's not even an issue). I doubt the laws will stay like this for long, I know in many countries (such as Italy) a bike without papers is practically worthless (and there's lots of 70's bikes in Italy that should have been salvaged back then, but someone thought it would be a shame and they stayed in some shed for years without any documents).


Cast wheels can be lighter than spoked ones, but I do not think that was the case with the early Japanese ones. I think I have a pair of 7-spoke cast Grimeca wheels stored somewhere, and I think those should be an improvement (they were used mostly by Laverda and Moto Morini, but also as aftermarket). Although, I definitely have some spare (more enduro) Akront spoked wheels for the Morini Kanguro. I think the bike would look better on spokes, and with aluminium rims they are not too heavy either. But then I'd probably need a 19' or 18' rim for the front (I doubt a 4-cylinder GS is the ideal choice for a dual sport bike )

Edit: A few more photos of my (other) bikes:


My 73' Honda CB360, and my 77' Moto Morini 350. Both have similar performance, but the Morini is so light and has far superior frame and suspension. Few bikes handle Like a Morini, but it is a lot more like riding on a horse, than the Honda (where you simply press the start button and take off like a gentleman).



Another Morini 350. Actually, I've recently had to rebuild the engine, and turned it into a 400 (also changed the cam for more lift). The 70's road model does perhaps about 170kmh, while this one is geared for only about 140kmh. It really jumps, and is fast up to 100kmh. Also very light, and I even prefer the handling of the enduro.



My ol' 77' V35 Guzzi. Unfortunately I've sold this one. It was a really early model, with lots of extra chrome, polished aluminium, two-colour wheels... These bikes were really low, and their frames were really good because the V allowed the tubes to go in the middle(unlike most bikes, where the frame goes over the engine, this kind of goes directly through it). It was also a really reliable bike - not in the maintenance-free way like most GS Suzukis, though. I rode with it a lot, and I'd say it handles even better than the Morini twins (even though it was much cheaper when new). Just overall great design. But the engine performance was really uninspiring.



These were very similar, but V50III models from the early 80's. They solved most of the gimmics of the very early models (the electronic ignition advance curve was really bad on those, the engine felt really dead under 3000rpm). The III models used the same engine as the sporty V50 Monza, but with classic styling. These were great bikes, had awesome handling (even the suspension was air-adjustable on the front and back), brembo integrated brakes, and enough power to really move.



My CB450 that I have recently bought. It did not have the correct seat, and I bought an original later - but it kind of does not fit well on the photo, because it was not bolted up yet. The 450 had an awesome design. Completely another league from the 360. It has the first CV carbs on a motorcycle, and they are really simple to work on, and the aluminium membrane does not tear with age like a rubber one. The float bowl is held on with a clip, and I've cut the gaskets for the carbs with scissors. A really reliable bike, but also designed to be intentionally easy to do repairs on. They are hard to ruin, but it's "achilles' heel" is revving it when cold - the oil pump was not that good and needs about a minute to build up enough pressure (afterwards, it does not matter if you constantly keep it at the redline). SOHC models usually have a "bath" of oil under the camshaft, so it's not too bad if you rev it cold, but DOHC over-valve design cannot be like that. And I really love that candy gold colour. In front is a 70's Guzzi V35 Imola (a sporty mini-Le Mans model, basically the same as a V50 Monza but smaller).



This was a BMW R100RT, that I modified into a CS. I was not really persuaded by German engineering - I think many things could be made much better. I sold it, although it was truly a nice bike to look at. I also have a 90's monolever RT, and I've worked on R90S models, but unfortunately BMW just does not do it for me (also an ancient frame design for the 70's, but it was the same through the 80's and 90's, weird forks with sheet metal triple tree, bad brakes...).



I got lots of other bikes too, but no good photos, and this is a GS forum after all

[Sasquatch]

Welcome to the forum. Lots of good info here!

[steve murdoch]

Welcome to the site, Pikl.
Some great looking bikes in your stable.
There was a red 3-1/2 near me that i would see about twice a summer. I remember that the stock exhaust had a lovely tone.

[pikl]

There was a red 3-1/2 near me that i would see about twice a summer. I remember that the stock exhaust had a lovely tone.

They do make a nice sound. Mine also has the correct mufflers now (on the photo, there were some really loud Italian aftermarket exhausts). It is really interesting how much power they were able to pull out of those tiny valves. But they proved big valves by no means necessarily equal more performance. The tiny valves and the flat heron head (combustion chamber in the pistons) made the fuel mixture flow into the cylinder at a very high speed, and created lots of swirls and turbulence (which makes the fuel burn faster). The piston had a big squish band, and most of the fuel was squished directly under the spark plug. That made a lot of power (probably the most powerful pushrod OHV 350, the sport model had about 40HP stock), and they were still very efficient. I know a few people who use them on classic motorcycle races (a friend actually modified Yamaha R1 pistons to make a high compression, high-revving 500cc engine, and he just flies past most other classic racing bikes on the track). Similarly, using a larger carburetor will not necessarily make the engine more powerful...

[Gorminrider]

Wow, pikl-very nice bikes! a good read!

[Burque73]

I got lots of other bikes too, but no good photos, and this is a GS forum after all

Very cool! Thank you for taking the time to share all those pics, GS or not, and great info!