GS650 Project bike ('82)

[elmocide]

I recently got this project bike that's frustrating the hell out of me.

IF it starts, it only fires up 1&4.

The carbs are spotless and the both coils tested as fine. There's compression on all the cyls, and the plugs are all giving a good spark.

The plugs are all brand new, the middle two are perfectly clean with a little bit of "soot" on the outer two.

I did the coil swap trick and the same outer cyls were still the only ones that fired up.


I'm waiting on the clymer manual hoping for ideas I havent tried yet, but wanted to check on here for things I may have missed.

[sloppydawg123]

Chances are it's the CDI/Igniter Unit. You can check the signal generator. The resistance between the signal generator wires (Blue and Green) should be 250-360ohms. If that's fine check you're connections, but it sounds like you have the same problem I do, I'm watching a few dyna systems on ebay, they replace the CDI and signal generator, and supposebly do wonders for an old bike, plus they are a lot cheaped than OEM parts. If i get it working I'll do a writeup on here, because I know you have to do some tweaking and fabbing to get it on there. If you email me, hilljason@comcast.net i'll send you a PDF service manual

[amateur]

I have a project pile of parts.

Potentially I have a GS650GLZ. A kid bought a running bike and tore it down to rebuild it better than it was. Thankfully he did not take down the tranny or carbs, but I too have a summer project.

Good luck on yours, I will need it for mine.

Amateur

[Suzuki_Don]

I don't think its the coils or the ignition since you swapped the plug leads around and it still only ran on the original cylinders. Check that the two problem cylinders are getting fuel to their carbs. Remove drain plugs from the two carbs concerned and turn fuel tap to prime and make sure plenty of fuel runs out of each carb. If no petrol then it could be stuck float needles/valves, a fuel blockage between carb feeds. Check valve clearances. I know you said you had good compression but still something to check. If you have good spark, fuel and compression then all cylinders should fire. One of these items must be missing.
Cheers
Don

[elmocide]

Check that the two problem cylinders are getting fuel to their carbs. Remove drain plugs from the two carbs concerned and turn fuel tap to prime and make sure plenty of fuel runs out of each carb. If no petrol then it could be stuck float needles/valves, a fuel blockage between carb feeds.
Cheers
Don

If there was a blockage in the feed, would both outside cyls still be firing?

The carbs themselves are spotless, but I havent checked (didnt even think of it) to see if fuel was getting to the two inner carbs.

If the two inner carbs arent getting fuel (under the feed blockage theory), how do I remedy that?

[mighty13d]

You said the inner spark plugs were clean.. clean and wet, or clean and dry? easiest way to tell if there's fuel.

[elmocide]

You said the inner spark plugs were clean.. clean and wet, or clean and dry? easiest way to tell if there's fuel.

Clean and dry, but theres gas coming out of the drain plugs for all four carbs, just checked.

Compression is fine on all 4 cyls, spark is fine on all 4, and gas is getting to the 4 carbs, but it's still not starting/running.

it started for 2 seconds using starter fluid/carb cleaner, but quickly died off and I couldnt get her to start up again...

I have the back boot/airbox disconnected while working on it, but it would start that way before. Pretty much lost at this point. The carbs seem to be fine, the plugs, and cyls as well. Completely out of ideas now.

[BassCliff]

Hee Haw Howdy!

Hi Mr. elmocide,

I'm sorry to hear of your troubles. Visit my website and download a manual. The troubleshooting section may help. These bikes do like their intake systems sealed. While you have the airbox off, tie a shop rag over the carb intakes temporarily. For more information, here is my traditional mega-welcome! \\/

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)!

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************
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

***********************************
Every GS850 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.
***************************************
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 cover gaskets, I recommend Real Gaskets (reusable silicon):
http://www.realgaskets.com
The Rice Paddy (salvage/used)
http://www.ricepaddymotorcycles.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
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

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)

[elmocide]

partial success

The bike will fire up now, granted with a bunch of sputtering and some smoke (white).

I kicked it into gear and did a quick loop to see what I was working with. She's bogging down bad in first, slightly less in second, almost choking herself completely out.

Would this be a spark or a fuel issue? If it's sputtering, it's getting too rich a mixture, right?

The help so far has been great, and I will post pictures of it when I get it running right (and the paint job finished).

Joe
\\/