petcock broke - kickstart ok, electric not?

[sthchen]

Hi,

I'm new to both riding and GSs, so sorry for any dumb questions.

I just got a 77 gs550 as my first bike, and it seems to have a broken petcock. When I put it on 'on' or 'reserve,' the bike sputters out on me after a few blocks of riding, as if it's not getting any gas, so what I've been doing (and what the guy who "fixed" it before me had been doing) is leaving it on 'prime' to run the bike, which works. I also turn it back onto 'on' when the engine is off so that the fuel isn't constantly going into the carbs, which from what I read here is bad (plus, the gas seems to leak a bit from the overflows if I leave it on 'prime,' which from what I read here is doubly bad).

I know that I should follow some of the excellent directions on here about rebuilding carbs and putting in a new petcock, but my question for now is this: with this tactic of mine, it seems to me that I can only kickstart the bike after I move it to 'prime' to start it. The electric start doesn't work, even with the choke - or at least, it seems that way. I don't understand that - what's the diff. between the kick and the electric such that that might be true?

Thanks in advance for any help you could give a newbie.

[sthchen]

one more thing

i should add that the electric start was/is working fine when the bike was constantly on prime, and the lights, etc., work.

[80GS750]

it shouldnt matter what position the petcock is in, it should start with the kickstart or electric either way....

maybe on prime your getting some leakage into the cylinders and the starter just cant turn it over enough to pop it off, but that doesnt sound rational to me...

does it pop off on the first kick, or do you have to kick it for a second or two???

try starting it in "on" and then turning it to prime so it will stay running, there should constantly be enough in the bowls to start it with the motor

[80GS750]

my recommendation is to buy yourself a petcock and get the float valves fixed asap... then you wont have to worry about either one...

get ahold of Z1enterprises.com for a petcock and adapter plate, you wont be sorry

[BassCliff]

Hee Haw Howdy!

Hi Mr. sthchen,

Here is your 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
http://www.bikepics.com
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)

[SqDancerLynn1]

I would bet the petcock tank filter is missing & some crap got into petcock
THE #1 priority when getting a bike back on the road after years of neglect is to clean the fuel tank & repair/replace the petcock !!!

[sthchen]

Thanks for the replies! I know...gotta replace the petcock. I'm just not a mechanic at all, so I'm nervous about it. But I still don't understand why it would cause (if it is causing it) a diff between kicking and electric start, or else I promise I wouldn't have asked yet another question about getting a bike running with a faulty petcock... =)

80gs750 - I have to kick it roughly twice. I tried electric starting in 'on' and turning to prime. But it just doesn't (electric) start in 'on' (unless the engine has been running for a while already).

[tkent02]

Thanks for the replies! I know...gotta replace the petcock. I'm just not a mechanic at all, so I'm nervous about it. But I still don't understand why it would cause (if it is causing it) a diff between kicking and electric start, or else I promise I wouldn't have asked yet another question about getting a bike running with a faulty petcock... =)

80gs750 - I have to kick it roughly twice. I tried electric starting in 'on' and turning to prime. But it just doesn't (electric) start in 'on' (unless the engine has been running for a while already).

So the engine will crank over but not fire?
Sounds like not enough electrical power to run the ignition while the starter is cranking.
Go through the Stator Papers, get it charging correctly, small problems here can get big and expensive if neglected.

Maybe even think about doing the relay mod on the ignition.

[80GS750]

so when its cold, does the starter turn over at all? or it just wont start?

if its turning over and just not starting with the starter you have electrical problems, probably a drop in voltage when using the starter and not enough left to spark the plugs enough to get her fired up....

like stated, go over the stator papers, check your battery, etc.... i think that will fix your problem