Runing Rich?

[Ike81]

Just got the bike back from a shop where they cleaned the carbs and cleaned and lined the fuel tank. You can smell gas in the exhaust which normally means it is running rich. There is a small popping noise sometimes that almost sounds like air is being forced out. Would resetting the idle speed help fix the issue or is there more to it?

 

[grizld1]

There's a lot more to it. Click the Tech button and follow the menus to the link for the Carb Guide.

Before you touch the carburetors, though, keep in mind that you need a hot spark at the right time and good compression for combustion to occur, so don't assume that the carbs are the source of your problem. Check everything else--compression, valve lash, cam chain tension, and ignition--before you fool with the carbies. If you don't have a manual, go to http://www.biker.net for a free download.

 

[Ike81]

All the above mentioned cleaning was done at a shop but has had the mentioned problem since I got it back. Don't know if it ran rich before hand or not tho as I just got the bike

 

[XSLeo]

Don't really matter what it did before, it's what it's doing now you have to contend with.
Get the repair manual. Find the carb guide. Your carbs may be clean but you have no idea what the jetting is. Follow the steps in the carb guide to tear down your carbs, Remove the jets so you can read the sizes, write all these things down.
Main jets, pilot jets, needles, needle jets, what slot the clip on the needle is in. Count from the top down. Number of turns out the idle mix screws are.
While your in there using a spray carb cleaner to blow through all the passageways will insure your carbs are clean.
The carb guide also has the specs for float height, mix screws and clip positions. Setting things to stock for the year of the carbs is a good place to start.
The guide also has a section on "Tuning for Mods" it works for stock bikes too.
Test what you have, then make one adjustment according to what the tests indicate should be done, test again, make one change at a time. this way you will know just what the changes are. Doing two or more adjustments at a time and you won't know what change helped.
Carb tuning can take time but well worth the effort. To have it done will take just as long but it can cost a ton of cash. Doing it your self will not only save money but help you become a better owner.
Leo

 

[grizld1]

Ike, since you're being encouraged to obsess on fuel, I'm going to repeat myself: poor combustion due to bad compression or bad ignition will have you smelling gas, fouling plugs, and assuming that a fat mixture must be the problem. If you make that assumption you'll be wrong more than half the time.Combustion is a tripod--it needs 3 legs to stand. Unless you know that compression and ignition are right, fuel system troubleshooting procedures won't mean a thing.

If you want to chase your tail, making assumptions is a great way to start. Check everything, and check it yourself. If learning to check everything looks like more than you want to deal with, you might be happier with a newer bike.

 

[peanut]

Just got the bike back from a shop where they cleaned the carbs and cleaned and lined the fuel tank. You can smell gas in the exhaust which normally means it is running rich. There is a small popping noise sometimes that almost sounds like air is being forced out. Would resetting the idle speed help fix the issue or is there more to it?

Ike welcome !

If I were you i would take the bike back to the shop where the work was done and ask them nicely if they would look at it .
Explain the issues that you have and ask them if they would remedy it.

You paid them specificially to clean and set up the carburettors and if you are not happy with the outcome they should be happy to look at them for you if they want to keep your custom.

I would personally recommend that you do not remove and strip your carbs Even experienced owners can find them difficult to tune and get balanced . This forum is littered with extensive threads about owners issues with carbs.
Get the shop to sort the problem if you can... if they cannot help then try and get some help from a local experienced xs650 owner

 

[grizld1]

Depends on what the shop was asked to do, doesn't it? If the shop was directed to do whatever was needed to get the bike running right, then a complaint is in order. But I've seen far too many situations in which an owner tells a shop to do only a particular limited job (just get it running, just clean the carbs, etc.), then brings the bike back with complaints that have been caused by something outside the scope of the work order. That's one reason why many shops refuse to work on older bikes--guys buy nonrunning machines cheap and don't want to put twice what they paid into getting the old iron roadworthy. Again--nothing in Ike's posts conclusively identifies the carburetors as the source of the trouble.

Let's add to the confusion. A full refurb job falls outside the scope of cleaning. If the shop doesn't have specific year-by-year data on XS650 carburetor components--and most do not--they may have done a fine job of cleaning while leaving a PO's incorrect components in place. If the owner doesn't look for himself, he's not going to know.

Bottom line--if you're going to mess with old bikes you need either very deep pockets or the patience to learn the machine and turn your own wrenches.

 

[5twins]

A guy brought a 650 into my local shop and told them to get it running for him. It had been sitting in his barn for several years. They did, cleaning carbs and doing a general tune-up. I saw the bill, about $550. The bike has sat there all summer, as far as I know, it's still there.

 

[peanut]

Depends on what the shop was asked to do, doesn't it? .

I don't think so

They were paid to 'clean his carbs' !......presumably because they were not functioning properly unless you can think of another likely reason.?

What is the point of the shop handing back a bike that still doesn't appear to be running properly.

His first port of call should be the shop who were paid to fix his bike.
If the shop found other work that needed to be done they should have informed the op when he collected the bike and paid for the work.

 

[grizld1]

That's assuming that the OP--or you--can KNOW that a carburetor is the source of trouble without inspecting everything else first. If you can do that, you're a much sharper diagnostician than I am. As to the rest of your argument, a shop that goes beyond the scope of a work order without a go-ahead from the customer is asking for trouble. You don't know the realities of the business or the machinery half as well as you seem to think you do. A few weeks spent as a gofer (they'd be nuts to let you wrench) in an independent bike shop would change your perspective in a hurry.

 

[TwoManyXS1Bs]

I have too many battle scars from that arena. Customer has pre-diagnosed his bike as "just needs plugs", that's all he wants, doesn't want to hear anything else. Plugs don't fix it, now it's OUR fault, and the bike becomes a regular 'return' or warranty job.

Some actually believe that the shop is incompetent, and demand that somebody owes them a living.

Others know this trick to get free repairs, or free diagnostics.

Either way, had to be able to recognize these guys early on, and send them somewhere else...

 

[grizld1]

Nah, TwoMany, John Customer doesn't think you owe him a living, he just thinks you don't need to make one! These guys bring a neglected barn bike in, say "Just get it running," expect a full refurb job, and want to pay south of $100--"But I only paid $200 for it!"

I'm comfortably retired, but one local indie shop occasionally calls me in on problem XS650's. The last one I worked on was a real gem. This clown had done a hardtail bobber, and he and his buddy--a "certified motorsports technician"--had pulled the motor to paint the frame. They had 12V everywhere it needed to be, but couldn't get spark. I asked the shop owner if the bike still had breaker point ignition. It did. I told him "OK, they painted over the condenser ground. You can fix it and charge $25, then have the fool blame you when he blows it up, or you can have me go through it, fix what needs fixing, and write up a condition report that covers your butt."

Checked compression first--no point spending money on a bad motor. Timing was set with full retard at around 5* BTDC and full advance around 45*, so bobweights had to be modified; the owner was headed for a holed piston. The goofs had hung the carbs in boots that had all the stiffness of firm foam rubber (we know where those come from), and on top of that he'd left the metal shrouds off. We didn't have replacements, so I wrote the problem up in the report to the owner. The battery ground cable had been replaced by a piece of 12 ga. wire--a custom touch, I guess.

I forget the rest of the flaws I fixed, but there were several. The bike went out with ignition recurved and strobed in, carbs synched, proper ground cable, and notes on defects. I gave two copies of the report to the shop owner, and told him to give one to the customer and have him sign the shop's copy. The tab was $250 to the shop. The owner didn't quibble, and the POS didn't come back.

 

[650Skull]

Hey Ike81, Peanut has a point if the mechanics didn't do what was asked of them, also some dirt may have dislodged from the petcocks after they cleaned the carbs so they done their job...................... Don't take to much notice of the fact there are multiple threads on problem carbs, in most cases the bike has been modified before the owner has learned about the bike or parts. There are just as many if not more members who have their carbs working great so they don't have to post asking for help.

Grizld1 is right when it comes to the experience of the mechanics working on a 30 + year bike. If the mechanic worked on these bikes when they were last produced then the chances are he is at least 52 years old, if he was 20 in 83. 70 was the first year of the XS so if he was 20 in 1970 he is now 65............. new shops or franchise shops just don't have the experience or want to know.

Forget about mechanics and shops for now and use the advice and help from those that know about XS650 carbs from here, you will save on money and gain a wealth of experience. Help others help you post the year and any mods about your bike in your signature. I went over an old post to find you have a 75XSB.

Read the "Carb guide" and note who wrote it, if your a bit confused then start a thread on your carbs and listen and learn. For a newbie it can be a bit confusing when there are differing opinions so it is sometimes prudent to check out members past posts as to experience. High post count doesn't necessarily mean experience.

When working on a the carbs do one at a time, be sure to have the right tools for the right job, take note of jet sizes and bag and tag parts. Doing one at a time will help, means the other carb can be used as a reference if things get confusing.