gs850 air forks question

[swisherred]

so I have yet another bike....1982 gs850G. I think the forks are low on oil, maybe blown seals..aside from the obvious taking them apart...what ride characteristics would I notice if the forks had blown seals or low/uneven amounts of fluid in them? it seems to ride low for one, and when stopped the forks dont seem to open back up after the forward force of stopping...until I pull up on the bars and then they slide right up with no noticeable drag like I would expect from dampeners. these are air assisted forks by the way. I use springers normally...not tubes, so i dont know a whole lot about them. any thoughts would be appreciated.
thanks

 

[rustybronco]

s it seems to ride low for one, and when stopped the forks dont seem to open back up after the forward force of stopping...until I pull up on the bars and then they slide right up with no noticeable drag like I would expect from dampeners.

you need to take them apart and examine them for that reason alone.
why are they sticking, no oil?
loosen the drain screws near the lower end of the outside of the forks and measure how much comes out of each side.

 

[BassCliff]

Hey Howdy Hey!

Hey Howdy Hey!

Hi Mr. swisherred,

You'll notice a mushy, wobbly ride, especially if you hit a bump in a corner. I would also suggest biting the bullet and fixing up your forks correctly the first time. Disassemble, replace oil, seals, check springs for wear, etc. Maybe even install some new Progressive fork springs. Then you can forget about using air pressure for preload. There's lots of 850G lovin' on my website. The link is below, here in your mega-welcome! :dancing:

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)![FONT=Arial, sans-serif] [/FONT]

Perhaps you've already seen these, but I like to remind all the new members. In addition to the carb rebuild series, 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.

Carburetor maintenance:

Replace the intake boot o-rings, and possibly the intake boots. Here's the procedure:
http://bwringer.com/gs/intakeorings.html
Here's an overview of what happens with this particular problem:
http://cycleorings.com/intake.html
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:
http://cycleorings.com
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:
http://thegsresources.com/gs_carbrebuild.htm

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.
http://denniskirk.com - Put in your bike model and see what they have.
http://oldbikebarn.com - seems to be slowly regaining a decent reputation, but it's still caveat emptor. They don't have anything you can't get elsewhere at a better price anyway.
http://www.babbittsonline.com/ - 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.
http://bikebandit.com - 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.
http://flatoutmotorcycles.com - Slow. Cheapest parts prices, crazy shipping costs. Don't expect progress updates or much communication. Real Suzuki part numbers.
http://alpha-sports.com - 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:

http://mcmaster.com - Fast, cheap shipping, good prices. No order minimum, but many items like bolts come in packs of 25 or 50. Excellent resource.
http://motorcycleseatcovers.com - Great quality, perfect fit (on original seat foam), and available for pretty much every bike ever made. Avoid the textured vinyl -- it's perforated.
http://newenough.com - You DO have riding gear, don't you? Great clearances, always outstanding prices and impeccable service.
***************End Quote**********************

Additional parts/info links:

GSR Forum member Mr. duaneage has great used upgraded Honda regulator/rectifiers for our bikes. Send him a PM.
New electrical parts:
http://stores.ebay.com/RMSTATOR or http://www.rmstator.com/
http://www.ricksmotorsportelectrics.com/index.php
http://www.electrosport.com/
For valve cover and breather gaskets, I recommend Real Gaskets (reusable silicon):
http://www.realgaskets.com
Carolina Cycle
http://www.carolinacycle.com
Ron Ayers Motorsports
http://www.ronayers.com
MR Cycles
http://www.mrcycles.com
Moto Grid
http://www.motogrid.com
Salvage/Used
http://www.ricepaddymotorcycles.com
http://www.ozpowersports.com/
If all else fails, try this:
http://www.used-motorcycle-parts.org/
Used bike buying checklists:
http://www.amadirectlink.com/roadride/Riderresc/checklist.asp
http://www.clarity.net/~adam/buying-bike.html
Lots of good info/pictures here:
http://www.suzukicycles.org
http://www.cyclechaos.com/wiki/Motorcycle_Wiki
http://www.bikepics.com
Basic motorcycle maintenance/repair:
http://www.dansmc.com/mc_repaircourse.htm
Online Clymer manuals:
http://search.ebscohost.com/ Click on "Small Engine Repair" then "Motorcycles". User=library, password=library. Note: This link may not work if you are on a school campus.


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,

BassCliff
(The unofficial GSR greeter)

Click here to visit BikeCliff's website.

 

[swisherred]

pics and such

pics and such

ok thanks for the welcome... looks like I have several things to look into. it runs pretty good for sitting for 8 years (PO) I rebuilt the carbs with the kit offered by someone here...cant remember who...viton parts..runs very well, but with a slight valve tick on the left bank..need to check the clearances there. The bike does exactly what you say on the forks and its ride...I dont see any oil, so i dont think the seals are blown, just no air...I rode it for awhile and things loosened up quite a bit so it all moves freely now, but it is deffinately out of air. I will post more in the newbie section on the bike. will order new seals anyway though and dig into the forks soon. thanks

 

[pbunyan850L]

Like Basscliff said though the fork tubes are not just air supported there are springs and oil as well. I think the big allen in the bottom is a 19mm and you need a long extension to reach it. Good luck!

 

[BassCliff]

Hi Mr. swisherred,

To stiffen up your forks, you can try running 10-15psi of air in the forks. Make sure both forks are equal. It's very easy to over-fill your air forks using an air pump at a gas station. It doesn't take much. A bicycle pump would be better. You'll also need a low pressure air gage. The air valves are on top of the forks, under the fork caps.

You could also try using longer spacers on top of the springs. But new Progressive fork springs are the way to go, when you get the chance.


Thank you for your indulgence,

BassCliff