Hi, new here with a question or two..

[nelsonic]

My dad got a GS550L X 1981 year.

When I took the carb set off, I found that someone had removed the main jets, and broke the float keepers..

So, I found another set that looked similar But they had slightly different spacing on them, so they didn't fit into the airbox, and manifold correctly.

Well, I took apart the middle two, and changed out the butterfly there, from the orginal set to the other ones. The bike did run with those before I changed the butterflys to make it fit better, but it never had any power to it.

I was hoping that changing the parts to make it line up better on the airbox and so forth, and cleaning the carbs (they were pretty bad inside, main jets almost fully plugged with gunk) I could get itto run better. Not knowing what the carbs came off of, I was going to check out the jets and stuff while I was at it, and set it up accordingly.

Now, I also got a bit confused about things when I looked at the specs here for carbs.

The type of carbs that are supposed to go on this bike according to the OEM specs I found on the sticky are 47160 (US) and 47170 (Can)..

Well, the first thing I noticed was that niether the ones that were on it to begin with, nor the ones I got are the same as this. The ones it came with are 47070, and the new ones I am putzing with are 45160.

I am not finding any luck identifying the differences between all of these.

The main jets on the new set are 115, according to the OEM spec it should be 92.5?

Another issue, I noticed that the throttle butterfly on the front of the carb has 130 stamped into the ones that the bike came with, and 140 on the new set I have.

According to the spec I saw, throttle valve should be 135, but niether of the two I have match this.

So, I am left with a serious question here.

SHould I just put them back on after cleaning them and see if they work better?

Should I get smaller main jets, and pilot jets, etc? Where do you find a diagram for these mikuni's that will also tell you the differences in model #'s?

I am also not sure if one of teh jets is actually a 115, I can't read it, the rest are 115's. How do I check to make sure they are the same?

I did wreck two of the float bowl gaskets. I found them for $12 each, is there a cheaper source?

Diaphragms look good, everything seems to work on these, I just need to have a few of these things clarified. I saw elsewhere on this site someone saying that main jets should be 115 for these. Maybe I should leave the jetting alone?

How easy would it be to find out what bike these were for originally?

Please advise..

Thank you,

 

[silverhorse47]

Could you say what the state of run was before you removed the carbs? Did it run when your dad bought it? If so, how well? Does the bike have original air intake and exhaust? Is there good spark to all the plugs? Is the air cleaner clean and sealed from leaks? Are the rubber boot connections between the air cleaner and the carbies leak free? Check them.

These will affect what you do with the carbs.

RE: the broken float flanges...you can JB weld them if you are careful, or use any quality epoxy that is rated to work with gasoline. Wax the pin to keep it from sticking to the epoxy, and be careful with alighnment. Use a dremel or riffler to remove any ooze-out. Perhaps the bike was sold because someone else got frustrated after putting on the wrong carbies?

It might be best to go back to the original carbs unless the differences between the new and old are very minor. I don't know about the numbers on the throttle plates and such, but I suspect that any real differences would be apparent if you look closely, ( ie is one larger/smaller?), and it sounds like you have. The numbers may just be production numbers or some such.

Make sure all the tiny passages are clear (see carb cleanup series) and replace all the o-rings and rubber plugs in the carbs. (Robert Barr).

Once you are certain that the carbs are whistle clean and you have reliable spark to all cylinders others will chip in.

Good luck!

S.

 

[nelsonic]

Bike was nonrunner when bought. Carbs were in pretty bad shape (missing floats/ main jets/ who knows what else) so I found this other set a guy had laying around, but he didn't know what they came off of. They looked very much alike, so we put them on the bike. The spacing was different on the middle two carbs (thus throwing it off for the rest too) but we manhandled it all onto the manifolds, but couldn't get a good seal on the airbox. Thing ran, and not too badly, a little weak, and sluggish, rpms kinda hovering when you let off the throttle, etc. Not bad for carbs just laying around shoved on just to see if the bike kicks over.

Well, My cousin (who is living with my dad, who also is doing most of the work on this thing til now) had been driving it like this, and I was worried that it was running lean due to the airbox leaks, and I didn't want him to put a hole in a piston or something. So I took the carbs off, and switched the parts out of the original set to make the things all line up properly with the airbox and manifold.

While I had it all apart, I decided to give them a good cleaning. Run wire through the passages etc (I've done this sort of thing before, but my problem comes in where I don't know if this carb set was ever set up for this size engine) and found that the pilot an mainjets were gummed up pretty badly, #3 wasn't firing, and I figured out that pilot and main jets were both gummed up completely on that one. One carb the float valve wasn't working, so it was dumping fuel everywhere all the time (another reason I didn't want my cousin driving it as is) So, now I am trying to figure out what jetting I should use for this 550, it looks like the type of carb I have is a BS34, used on the 850's from some research.

Should one change the jetting if you are going to a smaller motor? SHould you go leaner, or richer, since it is delivering more air volume too?

I know people who know what they are doing sometimes put a bigger carb on a smaller engine, and it works out, but I don't know what I am doing here.

I'd like to go ahead and use these carbs if possible, since they were free.

Any advice would be appreciated.

I was thinking of just putting it all back together, and seeing how it runs, but I thought if there was any obvious no brainer changes, I could make them from the get go.

Otherwise, I was going to attempt a synch, and adjustments to the jets to improve drivability after I put them all back on.

So far, I need to buy two bowl gaskets, and at least one rebuild kit. Everything else seems to work on these. I figured if anyone had jetting advice, I could go ahead and buy the jets and stuff while I was at it.

I know, sometimes I just make more work for myself, right?:?

 

[Guest]

Get a rack of BS32SS carbs off Ebay. Clean them and put in the right jets and ride.

 

[robertbarr]

Get a rack of BS32SS carbs off Ebay. Clean them and put in the right jets and ride.

Probably the best idea. You could put a lot of money and work into your current carbs and still never get it right.

The spacing between carbs should be a function of the gangplate that holds them together as a bank. You haven't moved the 'new' carbs to the 'original' gangplate, have you? That involves separating the carbs from each other and (at least) using the 'original' interconnecting fuel and vent tubes. Headaches...

These bikes are also very sensitive to upstream conditions, i.e. airbox & filter. If those won't fit right, it'll never run the way it could.

The more horsing around it adds up to, the more sense it makes to find a good set of carbs from a 550, clean 'em up, and go from there.

 

[BassCliff]

Hee Haw Howdy!

Hee Haw Howdy!

Hi Mr. nelsonic,

This will also help get you started on your quest to bring your GS back to life. 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)![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************
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)

 

[nelsonic]

Well, thank you Basscliff for the welcome (and the deluge of info, I will have reading to do for a few days I see)

As to the other responses, I am not ready to buy another set of carbs yet.

I am still not convinced these are BS34s yet. They look exactly IDENTICAL to the ones that were on the bike to begin with. I even put the faces up against each other and the holes are exactly the same size.

The only reason I had my doubts about them were from the numbers on the side that I looked up on this forum, where someone said they were off an 850, and that they were BS34 size. Upon further looking into this, I find that 850's also came with BS 32's as well.

I have changed all the brackets and linkage to the carbs that are in better shape, they didn't fit well before, and there was clearly leaks fromt he airbox, since they didn't line up at all with the holes in it. I changed the linkage, and butterfly actuators to the new (to the bike) carbs, and now they should fit and line up and be happy so far as the leaky air stuff is concerned.

The boots for the intake are new, with new orings. That part was ok, we were able to bend those enough to make them fit, and like I said, it ran in spite of having the jet's all plugged, the airbox not fitting right, and so forth.

Now, I have cleaned out the jets and so forth, following the directions for the CV carbs found on this site. I was going to buy orings, bowl gaskets and that sort of thing, and was figuring I should maybe get the right jet sizes. UNfortunately, I saw in the OEM specs section that niether the carb set that was on the bike originally (WHich I have no reason to suspect was anything other than the stock carbs) nor the identical looking ones I took apart to make work match in part #'s. So, I am scratching my head trying to figure this out.

What if I buy another carb set from ebay for this bike and it doesn't match part #'s either? Where am I supposed to go with that? So, I am thinking I will just put them on, and if it runs rich with the 115's, I'll drop them down to the 92.5's, and pilot jet too. Does this sound like a better plan than just buying them form the get go?

I cannot find the original jets that were in the bike. That would have made this job WAY too easy, right?

Thank you for any help you give, I will peruse more of that info given, but I am sure it will take some time.

ANother question I have for anyone here..

Why is it when I type in Mikuni BS32 in Google, I get ZERO useful hits, but when I type in BS34, I get diagrams, exploded views, and all sorts of handy info, covering carbs that look just like what I have?

If indeed these are BS 34's I am thinking I should leave the jetting alone,a nd see how it runs first when I have the airbox sealing, and the jets clean etc. Right?

I am trying to avoid just throwing parts at this thing, I am fairly convinced this will go with what I have, it was running very well considering the other issues it had before. It wasn't firing on #3 at all due to severe clogging of all the jets, and the air box had visible gaps in it, sucking air right in. In spite of this, my cousin claims to have gotten it to go 70mph, I got it to go 55, but didn't want to push it too hard like that, so, maybe it is set up for pods already!

Anyhow, Thank you guys I will be posting further questions I am sure. Maybe even giving an update on this. Anyone want to start a pool to see if I end up buying some carbs from Ebay?:?

 

[SAN]

81 550L carbs

81 550L carbs

www.motorcyclecarbs.com has the jets and other parts for mikuni cv bs carbs. i have a 1981 550T, wich is same motor. im told and read on this web site www.gs-classic.de/index1e.htm (follow directions on start page) to use bablefish link to convert german to english.tons of info on all gs models made. some specs are diff, on european but they have international model info as well.easy to navigate once you convert lang.they have inside diagrams of cv or old 77-79 vm carbs. hope this helps. ill look and see if i still have my stock 92.5 jets. I installed stage 3 dynojet pods& ceramic blk MAC pipe.ill PM you if i find them. free. G/L! SAN