starting problem

[coop]

Newbie here got a 1979 GS750 just rebuilt her, renewed everything, new points, condensors and plugs. She will not fire up tries and then dies. Blew carbs out she fired up on direct feed replaced tank no joy! Will not fire up with direct feed now totally baffled

[chef1366]

If it fired with a work tank I'd check into fuel flow from the petcock and also the fuel cap vent.

[coop]

Need to quantify a bit post too vague. The fuel line and petcock are fine, the whole bike is sweet just will not start been riding bikes for over 30 years and always worked on my own, never had this problem before. Wondering if it is a carb problem just tried again will not fire up even with fuel direct in to them.

[BassCliff]

Hee Haw Howdy!

Hi Mr. coop,

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************
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 cover 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)

[coop]

Cheers and thanks for the welcome all the above have been renewed during rebuild and rechecked since the problem arose. Will put pictures up, doing this bike to sell on to get funds to rebuild my GS 1000 chop, will have another look tomorrow

[Hoges]

Don't suppose you've checked your float level? You could always remove the float bowls and make sure fuel is coming down and push the float back up to make sure its shutting off with the needle valve. Any fuel line kinks under the tank when it's put on is another check maybe. It can't be much thats for sure. Bloody frustrating type problem. Keep going with it and you'll get it.

[coop]

Finally got the bike running found some petrol residue deep inside the carbs replaced all o rings (thanks to cycle o rings). Left bike last night gone in to garage today to find fuel all over the bike!!(ruining new paintwork) New petrol tap and all seals but for some reason it will not seat properly has anyone else had this problem? No leak until I put in half a tank of fuel. Finding this rebuild very frustrating it seems to be 1 step forward 3 steps back

[Suzuki mad]

You haven't got the fuel tap on prime by any chance?

If not it possibly a stuck needle valve. Give the float bowls a gentle tap to see if it stops it.

Suzuki mad

[Headphase]

Is it leaking from the tank/tap or the carbs, sorry , doesn't seem clear to me.
If it is the tank/tap then...

I've got a spare tank and a petrol tap off a , errm , I canny remember, but a gs750 of some year or other.
I'm not far down the road from you if you want to try and see if the tap fits your tank , or even the tank fits your bike.

[coop]

It's leaking from the petrol tap it had a leak replaced seals seemed to do the job but now petrol everywhere

[Headphase]

well you're welcome to try this petrol tap I have lying around.
I'm only down the road in Mansfield Woodhouse.

[coop]

Thanks for the offer I tried a new tap got a few GS bits, found the problem, the seal is not sealing properly just need to find a way round it

[Headphase]

I got a pingel, and it came with some blue hylomar type stuff, I dunno if something like that would do it, it depends whether it is the tap itself or the seal between the tap and the tank I suppose.
Hope you get sorted out anyway, need a hand or that, gimme a shout. I have no idea what I am doing, but that can often be an advantage , hehe

[Suzuki mad]

There are two bolts that hold the tap on. If you reused the old ones they can perish. The newer ones sold here in the UK are part steel part rubber and once used the rubber part leaks.

The rubber seal that fits around the top of the tap and the tank base are still avaliable if its leaking there. If the tap is leaking from either the on/off lever or from the base then either NRP (www.nrp-carbs.co.uk 0161 832 8646) or Allens. (I can't find a link yet.)

Suzuki mad

[coop]

finally finished and promised pic

finally got the bike sorted passed MOT today but discovered a strange noise somewhere between a whine and a rubbing noise can't pinpoint it ( any suggestions welcome)looks like it's back in to my workshop