OK Just bought a 81 xs650 that has a stuck valve

rokel · New Member Joined: Jun 09, 2007 Posts: 8

So how screwed am I? Considering I have no mechanical training? The guy I bought the bike from gave me the parts to fix it. Is this somthing a novice can do? I bought this bike to build a Bobber but basiclly to learn how to work on it. I am sure I will have an arm load of questions for you experts. Thanks for running a great site. Cool

xsjohn · Last edited by xsjohn on June 17, 2007, 9:57 pm; edited 1 time in total

Pretty screwed.....is the valve is really stuck....never heard this one....How did you determine this.......

John

rokel · New Member Joined: Jun 09, 2007 Posts: 8

Great... The guy I bought the bike from told me. If you open up the cover you can see it does not move.

xsjohn

Will the crank turn ... but the cam won't......?... Hard to figure the problem from your description......Without mechanical experience a good manual could lead you through dismantiling the engine if that was necessary....It would be an experience........Being an 81 it would be somewhat simpler than the older point versions.........

John

rokel · New Member Joined: Jun 09, 2007 Posts: 8

Thanks John. When I am looking at the engine on the side with the kick start. There are 2 valve covers. I took the front cover of and when I try to use the kick start the valve doesn't move. The rear one does however. Also the Kick start arm does not recoil after it is pressed all the way down. Is that normal.

Thanks, Rob

xsjohn

Rob...Kickstart return spring is broken or off its peg inside the case....May just have to wind the spring and put it back on........"""Have you got a manual""".....If the valve is really stuck there may be other damage but if you can do it your self the parts are cheap and plentiful....

You will have to remove the engine and start from the top and start removing things until you get to the problem.....Nothing there that a good manual and some tools can't solve.....The manual should give you all the clearances and enough detail to let you do it..........Some beer may help...

If you get stuck there is plenty of help on this site........The way I look at these things is the worst that can happen is you can just screw it up....Hell we've have all done that........If you can do it it is nice to have something you can fix yourself......

John

rokel · New Member Joined: Jun 09, 2007 Posts: 8

Alright..I do have the "owners woorkshop manual" I have beer and "The way I look at these things is the worst that can happen is you can just screw it up" Is my motto for the project so this should be an adventure!

thanks

xsjohn

Rob....My engine comes out without taking off the air boxes....There is a long motor mount on the very bottom center that should come out last when taking the engine out.....And first going in.....This lets you rock the engine front to back leaving room to put the carbs on without dicking with the air boxes.....

Fold the generator back...don't have to unplug....Along with the left side case..Remove master link in chain..Going back don't forget the chainbefore theleft side case....No need to take the right side case off except to fix the kickstart..

The top motor mount just take the four horixontal bolts off and keep the mount together...Don't need to actually take the mount apart......Mark right left....Back motor mount is a pain in the ass...Mark the haves r and l.....Have a beer.....

Careful with the 4 front exhaust bolts that hook to the exhaust to the head...Use anti seize compound when going back on......

John

INXS650 · 650Rider Supporter Joined: Mar 22, 2007 Posts: 645

John, do you think it could be a worn cam lobe? Have you tried spraying some marvins mystery oil on the valve? Sometimes this can free "stuck" parts. Have seen it free up a locked up motor. I would think if the valve was stuck, it would be extremely hard to turn the motor over. May just be bent alittle?

xsjohn

He will just have to take it down and see I guess......We don't know the history......Hard enough to fix them when you are standing over them.....

John

rwreed

Does the rocker arm move and the valve stay open? Or is the valve stuck closed. Is the valve adjuster just really loose? These might answer the cam question or valve stuck open.

Just my 2c,
Slim

rokel · New Member Joined: Jun 09, 2007 Posts: 8

Alright I got the engine out. What a procedure that was. Marvins mystery oil... I'll have to try that. I'm not sure if the rocker arm moves I'll check that too if I can. Thanks for the advice guys so far so good I'm still having fun...

xsjohn

Start taking the top off until you find it......Good time go farther and pull the cylinders and change the front cam chain guide (mikesxs 25 bucks and chain 50 bucks) so you won't have to do it again real soon......Read the manual and space the rings correctly...Align the guide and cam carefully so the chain rides in the center of the front guide...Measure the front guide so it is positioned in the cylinder straight...Bit of a 4 handed job getting the cylinders back on......Torque the head to max 35 lbs with anti-seize compound on the bolts......Then have a beer......Carbs are next if you think that was a hassel.......

Clean the carbs well before you put the engine in.....Later they are a pain getting out.....Autozone Dragons Fire carb cleaner and flush well with brake cleaner.......Big Fan behind you to blow the fumes or death may occur.......Life will get better....But it is hard to think so......

John

rokel · New Member Joined: Jun 09, 2007 Posts: 8

Great. This is starting to get good! I'll keep you updated

thanks

Rob

rokel · New Member Joined: Jun 09, 2007 Posts: 8

OK I have the top of the head of and have removed the camshaft chain tensioner and adjusted the chain to where the marked joining link is at the top of the camshaft sproket. Tomorrow I will need to find a tool to separate the chain. So far so good...

A few questions:

While dismantleing I noticed my engine did not have the "contact breaker base plate" or "ATU bobweights" How does this affect my engine? Do I need these 2 things?

Also when I pulled of the ATU housing it pulled of the cover of the bearings. Do I need new bearings now?

Thanks

Rob

INXS650 · 650Rider Supporter Joined: Mar 22, 2007 Posts: 645

Being an 81 model, you have electronic ignition, and thus no need for points. While you have the Head/valve cover off, you should be able to see the valve stems and cam lobes. You should be able to determine which problem you have with the valve if you can turn the motor over, and observe what the valve is doing. Does the cam lobe look worn? Is there alot of play in the rocker tip/valve stem area? This will give you alittle more insight into what you will need to do to get it back to correct.

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