1980 GS850GL Front wheel change- and front brake question

[msy3]

If I recall correctly, the 80, GS850GL has a 19" rim. I'm looking to change this to at least an 18" wheel to open up tire choices a bit and quicken up the front end a bit. I'm also planning on rebuilding the front forks (new oil- preload, possibly progressive springs) as well as potentially raising the forks 1/2 through the triple tree to change the stance a bit.

Are there any choices as far as a direct replacement for the front wheel?

Second, I replaced my front master cylinder (original couldn't be rebuilt) and have rebuilt the calipers and replaced the brake lines with SS. Front brake lever is still softer than I would like it. It's been bled a couple of times with no air coming out. Any tips or are they just a bit soft (used to my wifes, SV650, my MV Agusta F4 and my '86 GSX-R750).

Any help would be great as I'm fairly new to the GS850. Just got mine a couple months ago. (pics and profile setup coming)

msy3

 

[Steve]

Rather ambitious project there, but I think you are headed the wrong direction.

I think the only bikes that came with an 18" front were 450s, maybe the 550, I don't know. The problem there is that it might not be wide enough to properly support the tire you will need on the 850.

The 850 happens to be the HEAVIEST GS that was made, with the exception of the fully-equipped 1100GK. Yes, the 850 is heavier than the 1000G and the 1100G, both of them by several pounds.

You may see some ribbing about having an "L" bike, but don't worry, the steering geometry is virtually identical to the "G" bikes. Stick to the standard 100/90-19, it will be about as responsive and as stable as possible.

When you replaced the master cylinder, did you get one of the proper size for twin disks? If you happened to get one for a single disk, it will feel a bit mushy or vague, simply because it has to travel more to move two pistons. Also, did you prime the master cylinder before hooking up the brake line? Because of the construction, it is common to have an air bubble trapped in the top corner of the bore. Remove the handle, remove the brake line. Cover the outlet with a finger, but be ready to relieve a little bit of pressure. Use a dowel or a Phillips screwdriver to push the piston in as far as it will go. This is farther than the piston can push it, so it is more likely to remove that pesky bubble. Cover the outlet tightly, release the screwdriver. Repeat once or twice, then put the brake line back on and finish a "normal" bleeding session.

These are good bikes (look in my sig, you will see three 850s and two other GSes), but they are not quite up to the standards of newer hardware.

.

 

[msy3]

I did replace the master cylinder with a twin disk cylinder. It is working much better than the OEM one. I'll take a look at the MS and try your suggestion in case there is a small air bubble in the cylinder itself. Regarding the wheel, thanks for your suggestion. I'll stick with the 19. I'm sure by fixing/upgrading the front suspension a bit, it'll certainly help...and maybe get new tires as I have no idea how old the tires are that are on it now...but I'm guessing they have been around the block a few times.

I've seen some threads on modifying the seat as the double hump seat pretty much sucks as far as I'm concerned. Do the G models seats fit on the L? That would be easier than redoing the foam/upholstery. Finally, my tach isn't working so I'm thinking of replacing that and the speedo, is there anything I need to know regarding a replacement (gonna put different gauges on as I'm not all that thrilled with the dash as it sits now. Just a thought.

msy3

 

[msy3]

sorry, one more thing. I've been reading about this "GS Shim club"....what is that all about?

PS- I'll be emailing you about the spreadsheet once I'm near my computer (with email) as valves are going to be next on my list, along with carb sync.

now my brain is going...I have a mercury sync for the carbs, but no fittings on the end of the tubing. I see the allen screws on the intakes, where i assume I plug into for syncing. Any idea where I can get a fitting that will connect the tubing to the intake manifolds? I was thinking of a small banjo fitting with an 1/8" barb, but haven't found any yet.

 

[bwringer]

One thing I can't understand is why on earth you think you'd have better tire selection with an 18" front. Quite the opposite, actually. Maybe you're thinking of the rear tires, but there are tons and tons of options for your 16" rear as well.

You can get the adapters for carb synchronizing (and many other tasty goodies besides) at Z1 Enterprises.

You need the 5mm adapters for Suzukis:
http://www.z1enterprises.com/ItemDetails.aspx?item=MP08-0013

That's excellent advice on the front wheel -- stick with the stock 19", put some good sticky tires on there (Avon RoadRiders are my fave, Shinko 230 are good and cheap as well) and get the front suspension sorted out with fresh fluid and Sonic springs.

Get some good rear shocks as well. The stockers were dangerous crap 30 years ago. Z1 offers a few different options, or you can call up Dave Quinn for a set of Hagons.

Get the stock brakes working right, and they're surprisingly good. You'll need stainless lines, good modern pads (EBC or Vesrah) and OEM Suzuki rebuild kits for the calipers and master cylinder.

Overall, one common mistake is to start swapping parts around before you get the stock stuff working correctly. Your GS is capable of outstanding handling and braking in mostly stock form with modern tires in the correct sizes (100/90-19 front, 130/90-16 out back) a few suspension upgrades, and a refreshed braking system.

Suzuki started making great-handling bikes years before anyone else figured out some of their secrets of frame geometry and construction. A capable rider on a well-prepped GS850 can hustle down a twisty road at a shocking pace.

 

[Dogma]

... Maybe you're thinking of the rear tires, but there are tons and tons of options for your 16" rear as well.
...

One note here, and not to disagree with the thrust of the post at all, but the '80 850GL has a 17" rear. Many of the other L models have a 16" wheel, but not this one.

 

[bwringer]

One note here, and not to disagree with the thrust of the post at all, but the '80 850GL has a 17" rear. Many of the other L models have a 16" wheel, but not this one.

Good point!

Also, you reminded me that if stock braking is still deemed inadequate, there's a "twin pot" caliper upgrade bracket available. IIRC, you are quite happy with your upgrade.

 

[Dogma]

Good point!

Also, you reminded me that if stock braking is still deemed inadequate, there's a "twin pot" caliper upgrade bracket available. IIRC, you are quite happy with your upgrade.

Rather! Even though I recently experienced HH pads in the wet for the first time, I still prefer the new setup overall.

 

[msy3]

Thanks for the information. Turns out there are quite a few places to get the parts I'm looking for. That is a relief... Regarding the springs on Sonic, there are three spring weights available for the GS. Not sure what the base spring rate that is closest to OEM would be, but I'm about 225 lbs and ride fairly aggressively. Not sure what spring rate I would need. Any advice on that?

Also, I looked at the Hagon site and it looks like a good way to go. What are you running on your bike and is there any shortcomings that you've had with them (as well as the sonic springs)?

Starting to get the fall/winter list of parts and such together now so I can get ready to do some updates and stuff.

msy3

One thing I can't understand is why on earth you think you'd have better tire selection with an 18" front. Quite the opposite, actually. Maybe you're thinking of the rear tires, but there are tons and tons of options for your 16" rear as well.

You can get the adapters for carb synchronizing (and many other tasty goodies besides) at Z1 Enterprises.

You need the 5mm adapters for Suzukis:
http://www.z1enterprises.com/ItemDetails.aspx?item=MP08-0013

That's excellent advice on the front wheel -- stick with the stock 19", put some good sticky tires on there (Avon RoadRiders are my fave, Shinko 230 are good and cheap as well) and get the front suspension sorted out with fresh fluid and Sonic springs.

Get some good rear shocks as well. The stockers were dangerous crap 30 years ago. Z1 offers a few different options, or you can call up Dave Quinn for a set of Hagons.

Get the stock brakes working right, and they're surprisingly good. You'll need stainless lines, good modern pads (EBC or Vesrah) and OEM Suzuki rebuild kits for the calipers and master cylinder.

Overall, one common mistake is to start swapping parts around before you get the stock stuff working correctly. Your GS is capable of outstanding handling and braking in mostly stock form with modern tires in the correct sizes (100/90-19 front, 130/90-16 out back) a few suspension upgrades, and a refreshed braking system.

Suzuki started making great-handling bikes years before anyone else figured out some of their secrets of frame geometry and construction. A capable rider on a well-prepped GS850 can hustle down a twisty road at a shocking pace.

 

[bwringer]

I am about 280 pounds and my usual pace might be described as "bat outta hell". So I have the Sonic 1.1 springs on my GS850. There's a calculator on the Sonic site that should help you decide whether you need 1.0 or 1.1.

You don't want anything anywhere near the pillow-soft original springs... for 50 years (they're still doing this) Suzuki has been delivering bikes to the US with suspension suited for their 110 pound Japanese teenage anorexic test riders instead of normal humanoids.


As for the rear, my bike is wearing Progressive 12 series shocks with 120/170 springs. Progressive's usual "heavy duty" listing for a GS850 is laughably soft, so if you're 220 or more, just look for the springs listed for a Kawasaki Voyager.

Or, just call up Dave Quinn at Hagon, and he'll choose shock bodies with appropriate damping rates and springs with the correct sproingitude for your mass and riding style. This is also slightly cheaper than Progressives, and Dave is a nice guy.

Z1 Enterprises also sells Ikon shocks, which are a large cut above the Progressives and Hagons in quality -- and price. But well worth the added cash, I hear. I've never regretted a penny I've spent on suspension -- it's by far the best money you can spend as far as the increase in riding enjoyment and safety.