81 Gs750e Power Cutout

[alamohydroseed]

First Off, I Had No Idea There Were This Many Fellow Gs Ers Out There...great Site For All Things Gs.thanks

Anyway, Just Revived This Monster After 13 Years Of Sitting.went Through Most Everything And Got It Running Pretty Well. My Problem Is That When It First Starts It Is Great, Super Quick And Responsive, But After A Few Minutes It Cuts Out And Runs At What Feels Like Half Power. Still Runs Ok But Not Like When It Is Freshly Statred. After Which It Sounds Rough, Not Zippy. Its Sooo Close To Being There...but Not Quite.

[twistedwankel]

First Off, I Had No Idea There Were This Many Fellow Gs Ers Out There...great Site For All Things Gs.thanks

Anyway, Just Revived This Monster After 13 Years Of Sitting.went Through Most Everything And Got It Running Pretty Well. My Problem Is That When It First Starts It Is Great, Super Quick And Responsive, But After A Few Minutes It Cuts Out And Runs At What Feels Like Half Power. Still Runs Ok But Not Like When It Is Freshly Statred. After Which It Sounds Rough, Not Zippy. Its Sooo Close To Being There...but Not Quite.

Avoid my issue and drain/flush out the carb bowls until clean and examine the bolt tips for rust. That drove me nuts until I found it. Put inline fuel filter on and run a 1/2 can of Sea Foam thru the carbs in one tank of gas. Make sure battery has a very full charge as ignition needs more volts than the starter does.

Compression test WOT then Adjust valves (if needed) and then get carbs syncronized. At least then you will know where you are at. Maybe you will get lucky like me and not have to tear the carbs apart Then ride all day and nite.

Good luck.

[alamohydroseed]

81 Gs750e Power Cutout

Took It Out Today And Got Sporatic Bursts Of Power From The Engine. I Am Beginning To Think This Is A Valve Issue More And More. I Noticed A Broken Exhaust Bolt Where The Header Mounts To The Eng. And I Know There Are No Exhaust Seals On That Header. Could These Be My Problem? Kind Of Rattly On The Left Side Of The Valves Today. Thats Where The Broken Bolt Is. Also Lokking For A Stator So That I Dont Have To Keep It On The Charger.

[psyguy]

excuse me sir, but how exactly did you go "through most everything" if you have no header bolt, no header gaskets and dont know about the valves clearances :???:

these are some of the basics and unless you have these sorted you may end up chasing your tail

the list of possible causes is long so it would help troubleshooting if you could list the work done so far

however, the minimum for a good running engine is:
compression test
valve adjustment
no air leaks in the intake/exhaust system
carb clean, adjust, cync
good spark

keep us posted

[alamohydroseed]

Ok Ok I Get Your Point. I Still Have A Long Way To Go. Where Can I Get A Good Copy Of Some Valve Adjusting Literature? Im Going To Get Gaskets Today...and Work On That Bolt.

[psyguy]

valve adjustment

http://members.dslextreme.com/users/bikecliff/

[BassCliff]

Hee Haw Howdy!

Hi Mr. alamohydroseed,

These links/info should get you going in the right direction. It's your very own 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 (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.
***************************************
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

Basic motorcycle maintenance/repair:

http://www.dansmc.com/mc_repaircourse.htm

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)

[Griffin]

Intermittent issues are generally more electrical related than mechanical. If valves were bad, compression was low, or fuel starvation was the problem, then the bike would consistently exhibit the same symptoms under the same circumstances.

Oftentimes electrical issues only show up once a component gets hot, or vibration wiggles something out of place, and then it wiggles back. You mentioned the battery doesn't charge, that is the first place to start. Get a new battery, then check the charging system per the stator papers. Check spark on all cylinders, and check primary and secondary resistance of the coils, as well as plug caps.