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1981 XS650 Special 2

Gpaws1968

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Hi all,

I have bought a 1981 XS650 Special 2 and I'm looking in the manual for valve clearance there are different settings from the 650A, 650B, and 650C. How do I know if I have the A, B, or C?
 
Hi all,

I have bought a 1981 XS650 Special 2 and I'm looking in the manual for valve clearance there are different settings from the 650A, 650B, and 650C. How do I know if I have the A, B, or C?
You have an XS650H.
Intake: 0.06 mm
Exhaust: 0.15 mm

That is from the XS 650 SJ Service Manual and will apply to your engine.
 
Last edited:
Each manufactured year would get an alphabetical suffix in upward progression.
e.g.: my '77 is a D, '78 would be an E, etc.
So if my manual only goes to C then that's what I should follow? There is also a difference with the oil capacity
 
Thank you, there is no mention of H in the manual, how do you know, I am now to the motorcycle classic world.
The simple truth is I’ve had one of these bikes for 40 years and they've been multiplying in my garage. At some point many years ago, I joined the Yamaha 650 Society, then came the internet, rallies, XS650 friends, etc. So, learned a little.
 
So if my manual only goes to C then that's what I should follow? There is also a difference with the oil capacity
image.jpg


Get a factory service manual. Source #1. It’s not without flaws. The one shown 1982 bikes. You want H/SH
 
Someone will come behind me and tell you where to download the manuals. Expert opinions are coming too.

Your 1981 should have an oil viewing window on the left side of the engine. There’s also a dipstick. The stick is most accurate, bike level and wheels on the deck. When the stick shows full, oil appears at the bottom of the window. A bit too much oil goes out the breather.
 
Someone will come behind me and tell you where to download the manuals. Expert opinions are coming too.

Your 1981 should have an oil viewing window on the left side of the engine. There’s also a dipstick. The stick is most accurate, bike level and wheels on the deck. When the stick shows full, oil appears at the bottom of the window. A bit too much oil goes out the breather.
Do I screw the dipstick in to check the oil?
 
The dipstick.
Once you know the level is correct while resting it down on the bottom thread, screw it down and check again. You'll now have two correct measurements.
It's handy to know especially if the only thing available to wipe the dipstick off to return it to the bottom thread for a reading is yer pants.....
 
Welcome,
This link will answer a couple of your questions.

Has a link to online manuals.

https://www.xs650.com/threads/xs650...workshop-manuals-and-other-information.30569/

Just to confuse you if you had an A it would be a TX650A.
Your bike, being an 81H, is 7 years younger than the TXA

Alphabet prefixed bikes started in 74. 74-A, 75-B, 76-C, up to 81H/SH then they left out Ii and went to 82J/SJ then 83K/SK Heritage Specials were the last of the models. Some sold in 84 and 85 but they were left over bikes.

Different Countries/Continents got different variations of the models, production run varied between countries/continents.
 
Valve clearance specs changed several times during the production run, not sure why. Here's a little chart I put together .....

650ValveSpecs.jpg


It's become accepted practice to use .003" for the intake and .006" for the exhaust on all models. .004" on the intakes would be better as it would let more oil in but they often make too much noise if set that big. That was an issue on my '78 but closing them up just .001" to .003" quieted them right down.
 
So I did my valve clearances yesterday and it sounds so much better and seems to start better, but I'm confused on why the front rocker covers a different
 

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So I did my valve clearances yesterday and it sounds so much better and seems to start better, but I'm confused on why the front rocker covers a different
72-73 used a decompression lever, needed a stronger mount. They never changed the casting back after that.
decompression lever.jpg
 
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