Question about 1979 Yamaha XS 650 SF

1 Answer

I ran one of my carbs too rich and blew the left piston.

Is there anything out there that I can use as specific instructions on how to remove my 1979 XS6502f engine so I can get it repaired? I know I could probably purchase a shop manual, but perhaps, some other means is available. I need to do this myself to minimize the cost of getting it fixed. Thanks. Tim

Posted by on

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 20 achievements.


    An expert that got 10 achievements.


    An expert that got 5 achievements.

  • Master
  • 1,512 Answers

Hi fixx it
With the XS650, if you blew a hole in a piston, it has been  detonating on that cylinder, probably too lean more than anything. 
 There are some great forums out there that you can get access to with lots of information about the XS650. I own one myself, and have used this forums to rebuild my bike. 
for parts check out Mikes XS
for great advice on any dramas you are having
  650 Garage
  650 rider.
 The motors are easy to get out of the frame. One man can lift the engine, though I would recommend having someone hold the bike for you whilst getting it out.  I do have a link for a workshop manual somewhere, will get back to you shortly with that also.
happy to talk to you more about your classic bike. I love XS650's and ride one every day:)
regards robotek

Posted on Jan 04, 2009

  • 2 more comments 
  • Graeme Ross
    Graeme Ross Jan 04, 2009

    Here is another good site for info,  they had the link is was referring to an online manual, but the link is now dead.

     I will continue to see if I can find one for you that works. 

  • Graeme Ross
    Graeme Ross Jan 04, 2009

    Some good info on engine removal here.

     If you have not done much work on the bike  before, getting a workshop manual is well worth while and will save you LOTS of money in the future. With only a few tools, the bikes are relatively simple, and easy to work on. Makes a book well worth getting. Mikes XS has the Haynes book for $29, and if you are in the USA and get the order over $50, freight is free. Parts from Mikes are good value, buying the parts you from him will save you money also. 

  • Graeme Ross
    Graeme Ross Jan 04, 2009

    found a link that works. Go here for a FREE download of the XS650 workshop manual. 

  • Graeme Ross
    Graeme Ross Jan 04, 2009

    Hi tim, thanks for the rating. did you get the last comment with the link to the manual you needed? There are complete instructions bolt by bolt in there to remove the engine from the bike. Should sort out all  your needs. 


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

Factory carb settings

This can vary from year to year, model to model, and make to make. A service manual for your specific bike may shed some light on what the default settings are on your carbs. Sometimes a simple search on your year make and model of bike with carb adjustments can return the answer to your question. Here is an example: 1979 Honda CB750 Carb Adjustments. One other factor in this is the elevation you are at. At higher elevations the air is thinner making your bike run rich as there isn't enough oxygen to mix with the fuel. Once you know where your adjustments are, you can get them fairly close by slowly adjusting them with the bike idling. You want to turn slowly (1/8 turn at a time) until you hear the motor idle increase. For multiple carbs, start with one and repeat on all other carbs. If you continue to turn your jets after the idle increases, it will eventually start idling down again. I have been taught to try to find the boundaries going each way and seek the middle ground. Once this is performed on all carbs, you may need to adjust your throttle stop adjustment screw to bring yoyr idle back to specification. Good luck with your carbs, safe and happy riding to you.

Oct 15, 2013 | Suzuki Motorcycles

1 Answer

I have a 1979 harley davidson sportser with a ss super g carb that has been rebilt over the winter all was well till a month ago its started back fireing i put new plugs with no luck please help thank u...

You have an Ironhead Sportster that is running an S&S "G" model carb? Holy Smokes, that's way too much carburetor for that engine. Even the "E" model is on the big side for it. The venturi size of the "E" model is 1 7/8" with the "G" model coming in at 2 1/8". First off, are you sure it's a "G" model? It will have the word "shorty" and "E" or "G" on the side of the carb. It may be fouling spark plugs if it's too rich. What do your spark plugs look like, black dry puffy-looking soot on them? What size jets are in the carb? As you know, the temperature changes with the seasons and the fuel we now get is different with the ethanol that is blended onto it. These factors effect the performance of your carburetor. The first thing to do it to verify EXACTLY which carb you have. Then, go to S&S's site to their Techncal page, click on installation instructions, and look for the installation instructions for the Super "E" and "G" carburetor. Go here. Make sure you read the "Introduction" on page two. Print out the instructions and it will give you a guideline as to the jetting for whichever carb you have. Also, check your spark plug wires. Pay particular attention to the spark plug boot and the other end of the wire to make sure they are in good contact with the spark plug and the coil.

Good Luck

Sep 11, 2011 | 1979 Harley Davidson XLS 1000

1 Answer

A friend asked my to look at his bike. He blew it up and replaced piston... ran for 5 weeks and blew again. Got another piston and ring and it had NO compression . Long story short.. I ordered a NEW...

Hi,,ok that is a lot of wasted money spent,,the power valve plays little role in compression,,the FIRST thing to do is remove the flywheel and check the crank seal,,the compression has to be going somewhere,,,and the stator side crank seal is almost allways to blame(blows engines real fast,,sucks air,motor runs lean and bang!)

good luck

Mar 28, 2011 | 2003 Suzuki RM 125

2 Answers

Can you put a 1977 honda gl1000 carb on a 1979 gl1000

Yes it will run, but the 77 has different cams so the cam timing is different (more horsepower) The 79 is detuned and designed to burn leaner. In other words you may not see a performance gain and the mixture will probably too rich for the 79 (79 carbs are pollution controlled/which means harder to adjust yourself)

Oct 10, 2010 | 1979 Honda GL 1000 (K3)

1 Answer

1994harleydavison 1200 sporster sat a long time flushed tank and carb idl fine no hi speed after 3000 rpm ?

Sounds like your high speed jet is still stopped up. You didn't tell me what type of carb you have on the bike but what you've got to do is the same. You must remove the float bowl, remove the main jet, and clean it out. Also, clean the very bottom of the inside of the float bowl.

Flushing a carb will not clean the jets. The reason is that fuel must be able to flow though the jet in order for any chemical additive to clean it. If no fuel flows through, no cleaning action is taking place. That's why you must disassemble the carb and manually clean the small holes in the jets.

If you need more specific instructions, I need to know exactly what carb you've got on the engine. Good Luck, Steve

Apr 27, 2010 | 1979 Harley Davidson XLH 1000 Sportster

1 Answer

I have a 85 gsxr 750 running rich on the left

Hi Chris,
You will have to recheck the float level (in the float chamber) of those two carburators, reset if necessary.
You may also have to reset the air-mixture screw for both of those carbs. Standard procedure to set htem is tighten them all the way in making sure not to over tighten to avoid damaging the sharp end of the screw, and thn to open 2 and a half to 3 turns.
You can thn reset them as the engine is running + -- either way.
Hope this helps!

Dec 20, 2009 | 1986 Suzuki GSX-R 750 G

1 Answer


Sounds like dirty carbs. Remove them, soak them in combustion cleaner - NOT carb cleaner.

I had the same problem on my 1982 Honda DL500. I just removed float bowls, left everything else intact and soaked then blew out gently with compressed air.

Combustion chamber cleaner is much more effective than carb cleaner.
Hope this helps!

Sep 22, 2009 | Honda CB 750 Motorcycles

2 Answers

I have a 1979 rm 125, what kind of oil for the clutch?

Use 10w40 motor oil in the gear box. Don't use any synthetic oils, oil marked "EC", or oil with "special" additives. Stick with the major brands; Pennzoil, Quaker State, Mobil or Shell.
Use TWO STROKE ENGINE OIL in the pump. If not using an automatic oil pump, then mix the gas and oil 32 to 1. That equals 4 ounces of TWO STROKE ENGINE OIL to one gallon of gas. NEVER use motor oil in the gas. Only two stroke engine oil.

The lack of power probably has nothing to do with the clutch. More than likely you need new crank seals and possibly new crankshaft bearings. New piston rings are a possibility also. Remove the left side cover so yo can grab hold of the flywheel. Lift the flywheel up and down then left and right. If the flywheel is not rock solid you need new bearings. If you have to replace the bearings, also replace the sprocket shaft bearing and seal while you are inside the engine. For parts , go to the site below where you can see a parts diagram for your specific bike. You will select the actual brand, year, model, etc., once you go to the site. Part numbers and prices are also shown. You can order parts from this site. In the event no price is shown on a particular part and/or the notation "Not Available" is in the description, the part is not in stock.

Cleaning the carb jets may help with the power problem also.
ALWAYS have a fire extinguisher on hand when working on carburetors. Drain the carburetor. There should be a large plug on the bottom of the float bowl. Remove the screw then replace it after the fuel drains. Remove the carburetor from the engine.

Remove the float bowl and clean the entire carb with a spray carb cleaner from the auto parts store. Wear protective goggles to avoid getting spray in your eyes. Spray into all the little airways and fittings in the carb. Remove the idle screw and the air screw on the outside throat of the
carb and spray into the screw holes as well.
Be sure to put these two screws back in the same hole they came out of. IMPORTANT > do not tighten these two adjusters down. Only screw these in until they LIGHTLY seat. Now turn each adjuster one and one half turns outward. Before putting the slide back in the throat of the carb, move the clip on the jet needle one notch lower. Put the rest of the
carb back together, clean the air filter and install the carb. Let the float bowl fill then start the engine.

Can I get a “very helpful” rating on this answer?

Aug 22, 2009 | 2003 Suzuki RM 125

1 Answer

My '79 xs650 is popping thru the exhaust. It was fine last year except for leaking petcocks. I cleaned the taps and put new K&L kits in each side. Still have some trouble with leak thru to the carbs....

reset float levels and make sure that your needle and seat is not leaking and check that you have no air leaks on your inlet rubbers.

clean the carb properly and remove all fuel jets , needle jet and air screws before blowing out.

Jul 13, 2009 | 1979 Yamaha XS 650 SF

Not finding what you are looking for?
1979 Yamaha XS 650 SF Logo

297 people viewed this question

Ask a Question

Usually answered in minutes!

Top Yamaha Experts

Steve Sweetleaf
Steve Sweetleaf

Level 3 Expert

1128 Answers

D. E. Hev

Level 3 Expert

1059 Answers


Level 2 Expert

61 Answers

Are you a Yamaha Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides