Another build thread

ShaneWey

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Alright guys, I hate to start a new thread asking for help so soon but hher I am. So it looks like I get the opportunity to know my bike a lot better than I thought much quicker than I thought. I think I'm in for a rebuild. Not sure. I'll post a video.

There are metal shavings in my oil and on my filter. My oil also smells like fuel. I just don't know exactly what my next step is. What should I check for next? I know this is the start of a lot of work ahead.

 
Stating the year and model of the bike and some history and anything you have done to the bike is important for the right answers for the model.

making a build Thread is good, keeps all your information in the same place and easier for those answering as they can review all your information on what has been done.......That being said..........

Pics are better for diagnostic on anything except to hear noises when an engine is running. They can be enlarged to see detail and its easier to study for defects or differences.

Fuel in the oil is usually a stuck float valve. This is the last line of defense so if it is stuck open fuel can get past the carb......Solution is to open the carbs and check the float valve for bad or pitted seating or valve tip and replace if necessary. Pre 80 BS38 carbs have a steel tipped valve and 80 and later BS34's have a rubber tipped valve.

If your bike has vacuum petcocks then they could be defective and leaking fuel...........recent thread on this problem ..... http://www.xs650.com/threads/leaking-petcocks-on-1979-xs650-recommendations.54037/#post-579741.

metal shavings........use a magnet to identify if they are metal or alloy...........could be the Cam chain guide where the rubber has broken away and is rubbing
 
Ok yeah sorry for that. I put it in my signature. 1982 xs650. Pod Filters. Mikini VM34 carbs. Straight pipes. No vacuum on the petcock. Thanks for the info in pics. I'll post some soon. I'll have to go get a magnet too to identify whether it's steel or aluminum.

Only work I've done so far is carb adjustments with mixture and idle speed. I have a few extra Jets I've ordered but didn't want to take the PO word so I started from scratch and found this in my oil.

So do I start by taking the top end apart? Not sure what my next step is.
 
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OK... double check my old man's memory.... hold the plug to some ferrous metal and see if it's magnetic. Just to make sure I ain't losing my mind... :rolleyes:
 
Edit; VM carbs
Carbs2.jpg Carbs3.jpg Carbs6.jpg Carbs5.jpg Carbs4.jpg
 

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Sorry, I cant advise using an Adjustable wrench on sump plugs. To much movement in the jaws and chance the wrench can damage the plug, especially if the plug is stuck on..........get the right size and use an open end or ring spanner or a good quality socket
 
@Superjet

No.........using the incorrect tool because your in a hurry is just wrong...........This is why we have the term "the dreaded PO"

And no again.........There is the carb or petcock that caused the fuel in the oil situation that can be gone on with..........

Part of working on ones own bike is collecting the right gear for the job..........if that means stopping what your doing and going to get (or ordering and waiting for a few days), the right gear then that is what it is all about............

Being of a mind, and impatient, to get the job done with whats at hand because your in a hurry and can't wait will lead to problems like broken parts and worse case scenario cuts or broken bones..............
 
Yeah so the metal shavings are not magnetic so they must be aluminum. Jim's "old man memory" is still sharp. The oil plug is indeed magnetic. I'm not able to get the sump plate off yet to check for the filter for reasons listed above. Before I posted I took a crescent wrench to it and chickened out to the pressure. I'm going to buy the correct socket tomorrow.

I will get caught up on the threads you shared skull, thanks for that.
 
Shaneway says he has VM34's (you can see them in his video) Skull gives advice on how to work on BS34's :thumbsup:
 
Thanks for everyone's reply. I wasn't able to get the correct socket for the sump plate plug so I haven't yet examined the sump filter, however, still plenty of other things to do. I disassembled the carbs and took the exhaust off to have a look at the valves.

Inside is very dirty and it appears my right side intake and exhaust valve don't seat all the way. That would help explain the fuel problem. From what I've read, the manifold and valves sort of wear together so if I were to get just a new manifold or just new valves, they wouldn't seat right. Can anyone say anything on this?

As for the metal shavings, I've been digging around in the forum and found that it is likely my cam chain guide that would need to be replaced.

Here are some pictures of what I've done so far. Also notice the Cooper writ wrapped around the throttle screw at the top of the carb. To quote Forrest Gump, "I'm not a smart man, but I know what jerry rigged is."

Anyone know why the PO would have done this? He has some tape hiding this so I overlooked it on my initial inspection.
 

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The gap you're seeing in the valves is supposed to be there. Seats are cut to two angles... 45° and 25°. What you're seeing is the gap 'tween the 25° cut and the 45° valve face. In other words.... normal.

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Ok. It may be hard to see in the pictures but there is a sort of lip (which is probably part A) that the left intake valve tests on (looks like right at the 45 degree angle). However, the right intake valve seats probably 5mm lower (I guess at the 25 degree mark). Is it normal for them to be different? It didn't say in the Yamaha manual that I could see
 
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