Guide to Buying - Get to Know your bike, a checklist for the condition of your find

650Skull

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OK, you're a Newb, you just found an old Yamaha twin, and you're pretty sure you want to do this vintage bike thing.
Whether you're evaluating a prospective purchase, or you've already got the bike home, here are six easy steps to get the info you need to make rational decisions about this project.
Don't go off half-baked and just start tearing into or adjusting things - and don't start firing half-baked questions at the folks on your favorite newsgroup (hopefully XS650.com).
You'll waste their time as well as your own, and you'll waste money - this stuff gets expensive, as you'll soon find out.

First, disregard anything the Previous Owner might have told you. Probably all lies in the first place.
It would be great if the bike leapt to life and ran great first time you try, but it rarely happens that way in real life......

Get the Yamaha Manual

[1) Change the Oil - Just do it, don't even start the bike until you do it.
Examine the old oil carefully; look for color, metal shavings, bits of rubber, etc.
Smell it - does it smell of fuel??

Pull out the spark plugs and go here - this will indicate how the bike ran the last time it did run....
http://www.dansmc.com/Spark_Plugs/Spark_Plugs_catalog.html


2) Battery - the root cause of so many apparently unrelated problems.
The ignitions on these old Yamaha's runs totally off the battery.
They simply won't start and run ok with a compromised battery.
Worse yet, these batteries are about half the size they need to be, so it doesn't take much to hurt them. I've always held that I'd be glad to pack another 10 pounds on my bikes, as long as it was a bigger battery.
If your battery has been run completely dead more than 4-5 times, then it's been hurt.
Brand new batteries can be bad right out of the box, so be aware of that - happened to me just last summer.
If it's old, replace it.
If it looks weird, replace it.
If there's any question at all, replace it.
And buy a battery charger.


3) Compression - probably the #1 cause of problems with Barn finds and un restored bikes (once you get a new battery).......
These old bikes had pretty high compression, and most don't retain it after years of inactivity - even low mileage bikes.
Beg, borrow, or steal the use of a compression gauge - only takes a minute to do.
Warm engine, throttle wide open, no choke. Take readings at both spark plug holes a couple of times.
If it won't run, take the readings with a cold engine - generally only about 5 pounds or so less than a hot engine.
If the compression values are acceptable, resist any temptation to mess with the engine.

If the numbers are unsatisfactory, stop now, you have some serious problems. You are looking at a top end job, could cost you anywhere from $150-$300 or more, depending on what you find.
It is pointless to try and get the bike to run well; its not gonna happen, a waste of time and money.............
These are incredibly tough old engines - they will try and run for you no matter how bad they are, but don't be fooled.
Examples of MINIMUM compression values before top end rebuild is indicated
under- 100 psi poor
100/125 psi good
125/150 psi excellent
both cylinders should be within 10% of each other



Fuel - A word on fuel.
Yamaha is clear in the 650 manual - the bike was designed around 95 octane fuel. Back in The Day, that was "regular"gas. It is reasonable to expect that were all designed around this octane level.
It's hard to find gas like that today. I keep a couple of 5-gallon cans in my garage that have been treated with octane booster (on The Road, I do the best I can, like everyone).
Lots of folks will argue about this octane stuff, that's fine. It's your bike, after all, run whatever gas you please.
But I notice an easily perceptible increase in performance on my bikes when I run high-octane, they like it. So that's the last word for me.
My tractor and snow blower like high octane, too!!!


4) Timing - Next in order of potential for trouble is the ignition timing.
First make sure all your components, points/coils/condensers/wires/caps are all ok.
Remember, this stuff is around 35-40 years old now, that's not good for electrical stuff, it wasn't designed with a 50 year service life.
Also be aware that condensers have a limited shelf life even if they've never been used.
Parts are widely available for most stuff, and aftermarket coils are available for cheap.
MikesXS.com

Armed with their Clymer's manual, a lot of folks read "gap the points", and happily proceed to gap both points, not realizing they probably just screwed up their timing even worse than it was.
Go to the articles at xs650temp.proboards.com/index.cgi? to get an idea of the correct timing procedure for these bikes. The procedure is very specific to the Yamaha Twins, and must be followed to the letter.


5) Carbs - The carbs and fuel system.
Check the condition inside your tank - if there's rust, you need to do something about it.
Check the petcock - any leaks or sediment in there, does it work ok and deliver fuel to the carbs ok?? If the tanks rusty, the petcock most likely needs help.
Finally, are the carbs clean?? Do they have fuel in the float bowls?
Is there any leaking?? If so, you need to fix that right away, it will destroy the new oil you just put in..........
Now find the article at http://xs650temp.proboards.com/index.cgi? About setting up 650 carbs - the info applies to all the CV carb Twins of the era.


6) Running Gear - This is safety-first stuff.
Tires - if they're more than 4-5 years old, replace them. Don't mess around, just replace them.

Brakes - make sure everything works quietly and smoothly.

Drive chain - make sure it's in good shape. Grab the chain at the 3-o'clock position of the rear sprocket, pull it straight back. If it separates from the sprocket more than just a little, it's suspect.
If you have the chain off, hold it by one end and try to extend it horizontally "against the grain". If it sags like a rope, it's bad.

Swing arm - with the bike on the center stand, grab the rear wheel at the 12-o'clock position and push hard side to side (rider left to rider right). If there is any play at all, the swing arm bushings are bad, and the bike is not safe to ride, depending on the severity.
It needs to be very tight.

Forks/shocks - not much can be said about Yamaha's rear shocks of this era - they either work, (sort of), or not. Usually it's a matter of how much rust you can put up with, if they do work.
It would be prudent to drain and replace the fork oil. It's an easy procedure, and will let you know if there are any leaks (in a short while). Many times on barn finds, there's no oil at all in the forks. You can use regular fork oil, or you can use ATF, whatever strikes you're fancy.


Finally - You've now made a pretty good effort to do this thing. If you're still having problems, or just want to share your joy at success, now is the time to post your questions to the experts at XS650.com
You'll have accumulated much of the info they need to diagnose your situation, and performed many of the steps they would suggest in the first place.
 
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Buyers Guide Con't

ENGINE

what's really important is you don't try running it again until you get all the crap out of it and get things cleaned up right,. you could do serious damage. penetrating oil helps lots of things diesel fuel will too.. very important to change the oil though because the solvents will thin it and wear out your bearings quickly.

oil down the top end with product of choice.. through the plug holes and down the valve stems.. remove the carbs and the pipes and oil the exposed stems of the valves then let it sit overnight... turn the engine over by hand using the bolt at the alternator.. spray again.. let sit. change the oil... try running again to get it hot... let it sit... change the oil.. repeat until you reach a conclusion.

-use clean gas in a clean tank to rule out water vapor or contamination
-check your ignition circuit to ensure you're getting the hottest sparks you can.
-do a compression test and a leak down test before you pull it apart or have someone help you with this it could save you a lot of time and frustration and guessing in the end.

the white smoke.. is probably oil.. if it pours whitish from the front of your motor.. right out of the head.. and out of the exhaust.. it's guides or seals.. or both. I learned this the hard way. It could be water vapor also... air freely flows in and out of the motor and the condensation gets trapped and will not burn or compress.. as the oil heats up the vapor comes out of everywhere. scared the crap outta me., if it's bluish and out of your pipes only,.. it's probably rings or your bore.

they have a steel cylinder.. compression rings may corrode and possibly stick/scrape your bore on start-up. Penetrating oil into the cylinders and into the tappet covers, down the valve stems, gets everything slippery first. if the cyl. is corroded at all or has a ridgeline of rust.. get a machinist to bore them. you can use the ring gap measurements in three or four positions in your cyl. to tell you if the bore is serviceable if it is clean and corrosion free.

The motor likely was sitting with one or more valves down in the cylinder.. they tend to corrode inside the cylinder and then when you turn em over.. scraaatch... need new guides.. maybe.. mine did. Get a manual, disassemble it yourself, you can get a good idea of the condition of things just looking at where the oil or gas varnish traces run to before you clean it up. tells you where gaskets were leaking and if you look closely you can tell if oil was running down your valves too. If you take your valves out, be sure to deburr the top of the stem outside the guide before you slide it out.. any burrs or sharp edges will cut the %^&!! out of your guides. Very fine emery paper works well for this. clean it up good and re oil before you let them fall out.

if valves wiggle in their guides.. (check them closed, halfway open, and open) have a machinist determine if you can salvage the guides or valves or just opt to replace both guides and valves for good insurance. a machinist'll do it all for you for around 200 dollars if you bring them the parts.. may as well freshen it up while it's open. some guys can do this at home.. but driving the guide in perfectly in order to maintain concentrically of valve face and seat is reportedly nearly impossible without proper equipment.. I'd like to figure out a backyard trick for this one for sure.

If the carb is set waaaaay too rich ( totally wrong jetting) it'll smoke too,.. it's a greyish white smoke and smells acrid. but it's noticeably different from burning or evaporating oil smoke.

chance are if it's smoking relentlessly.. you're gonna learn to tear it down. but that's good, cause it's easy, you can do it yourself many times if you have to, the guys online will help,. and you can avoid


Stolen of a Honda site and modified for our mighty XS's by Jayel. I guess Honda have been good for something:laugh:
 
theres still alot of good looking cb 70s style bikes out there,iam redoing a little 550 with girder front end,hope to have it done by summer:cheers::smoke:
 
- good tips above...

- also, make sure you have a license, decide what type of motorcycle you want and why-obviously XS650s rule :D-and 2 sets of appropriate riding gear: gloves, boots, jacket-leather is kool but membrane is warmer, helmet, hard wearing pants comfortable in the crutch and knees-i like double knee carhartt or leather, sunnies...

- get a manual


BUYING USED

- whether you buy a used motorcycle from a dealer or an individual, compare the odometer reading with the condition of the bike...does it look right?...ask to see the maintenance and service records and receipts.

- look for rust and scratches on the bodywork, tank and fenders.. inspect footpegs for wear: worn on top means lots of miles...worn on the bottom means a rider leaning over too far in corners​

- a cracked or weather-beaten seat and faded, oxidized paint means the bike has seen a hard life​

- check for new or aftermarket parts obviously replacing broken ones... specifically, footpegs, mirrors, handlebar grips and brake and clutch levers​

- inspect the engine and transmission cases for oil seepage, weeping and leaks​

- chain should be clean and tight, about an inch of slack measured halfway between the sprockets along the bottom...rusty or grime-caked chains indicate poor maintenance​

- brake discs should be smooth, clean and not grooved, or blue-a sign of dragging/overheating brakes...check tyres for signs of abuse and age, tyres

- the bike should start easily and may emit a little smoke on a cold startup...if hard to start or billowing clouds of smoke-especially blue smoke-beware​
 
When I bought mine last year it had 14k miles on it for an 80XS. I took a guy who has ridden motorcycles most of his life. After all what would I know on a test ride. It started, ran smooth, no smoke, shifted well, only had a headlight issue. Once new brushes were installed I haven't had an electrical problem since. I did get rid of the glass fuses and do the inline blades. New tires as well, otherwise it has been a great starter bike. Need to redo the petcock but I am told as long as I don't run it out of gas I will likley be ok for around town riding.
 
Hey 650Skull,
GREAT starter list for us newbies!! This is info you (me) would find out after a long time being ignorant and frustrated and you've saved a lot of us from going through that with this checklist. You really are paying it forward to us that are new to the xs. THANK YOU !!
-from many of us
 
I am about to look at an XS that I know doesn't run. What are some things I should look for or do to determine the condition?

For instance, some folks says to try and turn it over to make sure it isn't locked up, but like previously said, trying to turn it over after it has been sitting for years, may cause more damage.
 
Read everything above 3 times. Make notes and take them with you. Don't fall in love with it is my best advise. Pick the sob apart. And never, ever, ever believe the owner. If it was so, "easy to fix" or "just needs a..." then they would have done it.
TITLE, TITLE, TITLE!!!!!!

Make sure it goes through ALL gears, put it in neutral and use the kicker to see if it will turn over, if it doesn't, and I don't care what the owner says; never, ever believe them; it's gonna need somekind of work. Take the plugs out to make this easier.

Also look for melted wires or "birds nests" wires. That means it's probably fucked up, Period!
Bring a battery with you!!!!! Even it you know it won't start, you can still check the electrical out. I looked at a bike and the owner said the battery was dead, "but the bike is fine" he said. You should have seen his face when I pulled one out of my truck. The bike was fried too, worthless.

Do your homework and be prepared to walk. Don't take shit from the owner, nothing. Don't even respond to them, just keep looking at every little part. This makes people nervous too. Let them talk, not you. You just ask questions, thats it. Seller's rehearse stories in their minds for hours and are ready to give you a great show. Do not buy into it. Straight questions and answers. If they start to tell some story about what they did back in high school during the last game of the season, the big play...stop them with a question about the bike. You're there to buy a bike you know absolutely nothing about and they want your money.

Sounds kind of mean to some people that you should act like a cold ass, but that's life. You'll feel a lot better when you realize you didn't just spend a whole lot of money on a piece of shit that needs $1,000 worth of parts just to get it running.
 
Do your homework and be prepared to walk. Don't take shit from the owner, nothing. Don't even respond to them, just keep looking at every little part. This makes people nervous too. Let them talk, not you. You just ask questions, thats it. Seller's rehearse stories in their minds for hours and are ready to give you a great show. Do not buy into it. Straight questions and answers. If they start to tell some story about what they did back in high school during the last game of the season, the big play...stop them with a question about the bike. You're there to buy a bike you know absolutely nothing about and they want your money.

Sounds kind of mean to some people that you should act like a cold ass, but that's life. You'll feel a lot better when you realize you didn't just spend a whole lot of money on a piece of shit that needs $1,000 worth of parts just to get it running.

LOL:D:thumbsup: FUNNY FUNNY TRUTH.
 
I think some of the biggest things people should ask themselves FIRST is.......

am i mechanically inclined enough to deal with a vintage bike, and am i patient enough to sit around and fix if need be during down time?


To many people want vintage bikes, and then seem frustrated when shit is broken or doesn't run right. It's an expensive hobby and requires a ton of patience.
 
I think some of the biggest things people should ask themselves FIRST is.......

am i mechanically inclined enough to deal with a vintage bike, and am i patient enough to sit around and fix if need be during down time?


To many people want vintage bikes, and then seem frustrated when shit is broken or doesn't run right. It's an expensive hobby and requires a ton of patience.

+1^
These bikes, an mostly any old bike, are not something you just hop on and ride around, then throw back in the shed 'til next time.
I ride everyday and I'm always doing something in my spare time to my bike.
 
First post on the forum so be gentle. I just picked up my first bike ever, a 77 XS650. It looks a bit worn, but machanically it seems to be in great shape. Starts on a couple of kicks or on the first push of the starter button. It runs like a charm as well. The last owner just changed the engine- and fork oil, and said that if I needed help doing it again during the summer I could just drop by his workshop. Bike seems to be in good shape so I don't want to mess to much about and ruin it, but I would like to make sure that everything is ok. Should I just start at the top of the list or should I just ride it and be aware of any changes that may come? The only thing I've noticed so far is that it backfires a little when I'm motorbreaking. Is it running a little rich or it that just how it is?
 
Welcome to the forum Fossi!
Chances are it is running a little lean causing the backfire.
Count your blessings on buying from a person that has encouraged you to come back for help.
If it is running and riding, do just that. Maintenance issues will pop up but you didn't buy to just work on. Did you?
It is quicker to get the manual to follow, but you can pretty much learn ALL about these bikes on this and other forum boards.
Oh and we love pics........post'em up in the "lets see the XS's" thread.
 
Ok, thanks Weekendrider. I will look into it. I got the manual from the last owner and this site seems superb so it looks like I'm in good hands. I bought the bike to ride it, thats why I bought a japanese bike and not a british one :) But I got some good ideas when I first saw the bike so I'll probably end up ruining it trying to make it look the way I want to. Luckely the former owner works in the university workshop so I hope he can work miracles
 
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