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Dear fellow GS rider,

Let it be known that on this day you are cordially and formally welcomed to the GSR Forum as a Junior Member in good standing with all the rights and privileges thereof. Further let it be known that your good standing can be improved with pictures (not you, your bike)!  I'm not kidding!

Perhaps you've already seen these, but I like to remind all the new members. In addition to the 
CV Carb Rebuild Series (by John Bloemer), the Mikuni BS(CV) Carburetor Rebuild Tutorial (by Ed Ness), the VM Carb Rebuild Guide (by Paul Musser), I recommend visiting the In The Garage section via the GSR Homepage and check out the Stator Papers. There's also a lot of great information in the Old Q&A section. I have some documentation on my little BikeCliff website to help get you familiar with doing routine maintenance tasks (note that it is 850G-specific but many tasks are common to all GS bikes). Other "user contributed" informational sites include those of Mr. bwringer, Mr. tfb and Mr. robertbarr.  And if your bike uses shims for valve adjustments, send an email to Mr. Steve requesting a copy of his Excel spreadsheet that helps you keep track of clearances, shim sizes and other service work.

These are some edited quotes from one of our dear beloved gurus,
Mr. bwringer, with ideas on basic needs (depending on initial condition), parts, and accessories.

***********Quoted from Mr. bwringer************

Every GS850 [and most other models] has (or had) a set of well-known issues that MUST be addressed before you have a solid baseline for further troubleshooting. It's a vintage bike, and it's quite common (as in, every single GS850 I have had contact with) that there are multiple problems that have crept up and slowly gotten worse over the years. It's not like a newer vehicle, where there's generally one problem at a time.

These common issues are:

1. Intake O-rings (install NEW OEM or Viton only - common nitrile O-rings will quickly deteriorate from heat)
2. Intake Boots (install NEW -- these cannot be repaired)
3. Valve clearances (more important than most people think)
4. Carb/airbox boots
5. Airbox sealing
6. Air filter sealing
7. Petcock (install a NEW one)
8. On '79 models, install new points or Dyna electronic ignition (or at least verify that the old points are working correctly)
9. On all models, it's fairly common to have problems with the spark plug caps. These are $3 or $4 each, and often worth replacing if you're keeping the stock coils/wires.
10. Stock exhaust with NO leaks or holes -- good seals at the head and at the junctions underneath.

What I have noticed at the rallies is that very, very few 850Gs are actually running right. Make VERY sure it's actually running the way it's supposed to before busting out the modifications.

Brian's E-Z and fun plan for GS850 happiness:

1) Seal the airbox and air filter with weatherstripping.

2) Ensure no intake leaks. Spraying WD-40 or water doesn't tell you much, since very small air leaks can cause problems even though they won't suck in enough WD-40 to make a difference. Replace your intake boot o-rings and boots if needed, and seriously consider spending the lousy $28 for new airbox/carb boots.

3) Ensure clean carbs with correct settings, new o-rings, and original OEM jets. No, not just squirted with something. I mean completely disassembled.

4) Check/adjust valve clearances (Manual calls for every 4,000 miles. This is not optional.)

5) Ensure healthy electrical system.

6) Seriously consider upgrading coils and plug wires.

7) Install new, stock NGK B8-ES plugs gapped to .031".

8 ) Fine-tune float height and idle mixture screw to ensure best off-idle transition.

9) Clean air filter and reinstall with only the lightest oil mist -- over-oiling and/or letting the filter get dirty is a common and critical mistake, and will make the bike run funny at low speeds and run rich. This may take a few tries.

10) Make sure the exhaust seals are sealing.

11) Ooh, much better now, huh? You're gonna need upgraded suspension - Progressive or better fork springs and shocks. Set suspension sag appropriately.

12) Upgrade brakes with new pads and stainless lines to deal with all that extra speed.

13) Install new petcock, since I'm going to head to the roof with a rifle if I have to read about yet another #2 plug fouling and failed hillbilly attempts to rebuild the petcock and/or deny there's a problem.

14) Oh yeah -- check compression somewhere in there to ensure the valves and rings are reasonably healthy.

15) You'll probably need new OEM clutch springs -- the clutches last forever, but the springs get tired after 20 years or so under pressure. E-Z and cheap.

Carburetor maintenance:

Replace the intake boot o-rings, and possibly the intake boots. Here's the procedure:
Here's an overview of what happens with this particular problem:
You'll also want to examine the boots between the carbs and the airbox. There's a good chance these are OK, but check them over.
And finally, if things still aren't exactly right, you'll want to order a set of o-rings for BS carbs from the GS owner's best friend, Robert Barr:
Once you receive these rare rings of delight, then you'll want to thoroughly clean and rebuild your carburetors. Here are step-by-step instructions that make this simple: (for CV carbs)

Or for VM carbs:

OEM Parts/Online Fiches:

I would definitely double and triple the recommendations to use
Cycle Recycle II and Z1 Enterprises as much as possible. These guys are priceless resources. Z1 tends to have slightly better prices, CRC2 has a wider range of goodies available. If you're near Indy and can bring in an old part to match, CRC2 has a vast inventory of used parts. - Put in your bike model and see what they have. - seems to be up and down as far as reliability. Use as a last resort. (Check their Closeout section for good deals.) - Decent parts prices. Spendy shipping. Don't give you part numbers at all. Useful cross-reference if you obtain a part number elsewhere. Efficient service. - Fastest. Middlin' prices. Uses their own parts numbering system to obfuscate price comparisons -- can be very confusing for large orders. Cheapest shipping, so total cost usually isn't too bad. (formerly - Sometimes slow. Cheapest parts prices, average shipping costs. Don't expect progress updates or much communication. Real Suzuki part numbers. (Note: Chris@flatout is a member of the GSR forum.  He has worked hard to improve communication and delivery speed/cost.  Lately the reviews have been very favorable.) - Exorbitant parts prices. Different type of fiche interface that's quite useful at times, especially with superceded part numbers. Real parts numbers. Shipping cost and speed unknown due to insane, unholy pricing.

Stainless Bolts, Viton o-rings, metric taps, dies, assorted hard-to-find supplies and materials, etc: - Fast, cheap shipping, good prices. No order minimum, but many items like bolts come in packs of 25 or 50. Excellent resource. - Great quality, perfect fit (on original seat foam), and available for pretty much every bike ever made. Avoid the textured vinyl -- it's perforated. - You DO have riding gear, don't you? Great clearances, always outstanding prices and impeccable service.
***************End Quote**********************

And now, a few words about fork springs and rear shocks, from Mr. Griffin.  (Comments in parentheses are mine.)

**********Quoted from Mr. Griffin**********

For suspension upgrades, the front end is pretty simple: Progressive brand springs and fresh 15W fork oil. ( has pretty good prices on Progressive products.)

(If you need extra heavy spring rate for your forks (for bigger riders or heavy loads) try Sonic Fork Springs. There's an online tool for calculating the proper spring rate according to your bike, weight, riding style, etc.)

The rear end isn't so simple.

Most of these brands are available in 'eye to eye' and 'eye to clevis' configurations, in different lengths for twin shock GS models. The options are arranged in order of price, low to high.

1. $65-$90 Emgo/MDI: Found all over ebay, and at about every vendor on the internet. General consensus of users seems to be that they are ok quality, but very stiffly sprung. Essentially the bare minimum option from stock. (For example, see:

2. $120 Redwing: Evidently no longer made, they are still available at (and I've not been able to find anyone who's actually used them, but they appear to be of halfway decent quality.

3. $210-$230 Progressive 12 Series: Lots of information here and all over the web about them. Most people seem happy with them, several different spring weights available. Available at most online retailers. is a vendor I have had great luck with over the years.

4. $218-$270 Hagon Type A: Seem very similar to Progressive 12 series as far as owner satisfaction, quality of construction, and price. Available in the USA at

5. $320-$400+ Ikon 76 Series: Generally pretty highly regarded, lots of options available. From what I've read on the internet, they do seem to be more highly regarded than Progressive. Can be found at

6. $419-$589 Works Performance Steel Tracker: Very highly regarded, lots of positive reviews around the internet of Works Performance in general. Customer service (including rebuilding any brand of shock) is very highly rated. More info at

There are other options available that can be more expensive, including offerings from Works, Ikon, Ohlins. White Brothers, once a powerhouse in the motorcycle industry, has ceased operations.

(Note from BassCliff: Also check out YSS Suspension at

**********End Quote**********

A Few Words About Oil

I'll tell you what I use and why. I use Rotella-T Heavy Duty 15w40 oil. It is actually diesel engine oil and contains more anti-wear additives, phosphorous and zinc, that these older high-revving engines love. At about $12 a gallon from Wal-Mart, it's less than half the price of many motorcycle-specific oils, and is the best "bang for your buck" value. The synthetic Rotella-T is just fine too, it won't hurt your clutch. If you like, continue reading the links below for everything you ever wanted to know about oil but were afraid to ask.

Here's a great article on motorcycle-specific oil in general.

Here's a 2nd great article, also on motorcycle-specific oil.

Sport Rider Magazine ran a feature awhile back on motorcycle oils as well, and included some testing with detailed results provided. Well worth the read!

Sport Rider "Oil's Well That Ends Well" Part 1

Sport Rider "Oil's Well That Ends Well" Part 2

Richard Wildman (of Richard's Corvair) explains in layman's terms all about grades, viscosity, shear, additives, specs, etc.

Richard's Corvair - Selection of the Right Motor Oil for the Corvair and Other Engines

And, of course, Bob the Oil Guy is a fountain of information.


Additional parts/info links:

New electrical parts: or - Stators, r/r units, etc. - Stators, r/r units, etc. - Stators, r/r units, etc. - Starters, etc. - Batteries, etc. - Big Crank Batteries
- Batteries, etc.
- power all kinds of motorcycle accessories. - allows simple and easy installation of electrical components.
A source for "vintage" electrical connector parts:

New Exhaust Systems:
Vance and Hines -
Mac -
SuperTrapp/Kerker -
Laser/Jama -

The Image Works - Old, new, vintage, obsolete, rare graphics and stickers.
Reproduction Decals - Specializing in 
obsolete and unobtainable decals for vintage motorcycles.
Valve cover and breather gaskets, I recommend Real Gaskets (reusable silicon):
Brake Lines - Stainless steel lines, stock kits, custom kits
Sudco International
- Carburetor parts,
Classic & Late Model Replacement & Performance Parts, etc.
Jets R Us - Carburetor parts, filters, gauges, etc.
Parts'n'More - Classic UJM parts (i.e. gasket sets): $35 minimum, $5 shipping to lower 48
Motorcycle Accessory Warehouse (Searching by mfg. part#? Leave out the hyphen '-')
Motorcycle Superstore - tires, accessories, apparel
(Located in Oregon, fast shipping to the West Coast, free shipping over $75)
Fly-N-Cycle Motorsports - parts, accessories, apparel
All Balls Racing
- bearings and seals
Boulevard Suzuki
Cycle Parts Nation
G&S Suzuki
Carolina Cycle
Ron Ayers Motorsports
MR Cycles
CMS-Parts - Parts fiches for non-US bikes
Moto Grid
Full Throttle Motorsports
Paint Codes - 
Use this chart to cross-reference the Color-Rite color codes to Suzuki factory codes.
Motorcycle Shipping
If all else fails, try this:
Used bike buying checklists:
Lots of good information/pictures here:
The Motorbike Archives - Online motorcycle magazine articles, tests, features, competitions, etc
Motorcycle Info and Accessories - TONS of good info here
Suzuki Engine and Frame Numbers
VIN Decoder (17 digits) for Suzuki Bikes
Basic motorcycle maintenance/repair:
Beginner's Guide To Motorcycle Wiring:
Suspension Tips and Tuning:
Online Clymer manuals: Look in the "Small Engine Repair Resource Center" for "Motorcycles" and you will find online Clymer manuals for many bikes.  See your city library or school library for access to the EBSCO databases.
International Title Service - Does your bike need paperwork?
Parts Cross-Refernce:
Put your part number in Babbit's search engine and find out what bikes use the same part (Use the "Quick Lookup").
Other Repair/Tips Links: - Repair the broken posts on your sidecovers. - The art of extracting snapped bolts. - Everything you always wanted to know about motorcycle chains; replacement, maintenance, etc.

Thanks for joining us. Keep us informed of your progress. There's lots of good folk with good experience here.

Thank you for your indulgence,

(The unofficial GSR greeter)

Welcome! Come and get your healthcare!

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