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Pulled the cover and did a motor seize test: Motor will turn about 20 degrees in either direction but will not complete a full revolution.
what is happened when you turned it? did it get harder and harder to turn, or did it go clunk like the piston is hitting something?

When the spark plugs are in the motor will build compression just turning it by hand. The wrench will feel like you are loading up a spring (you are, an air spring...)

If that is the case you can either take the plugs out and try again, it should feel the same all the way around

or if you are sure its just the compression you can put a little more force on the wrench and push it past the compression stroke.

And again, only turn it clockwise. There is a timing chain on both cam shafts with a tensioner. The chain pulls the cams around in the clockwise direction, and the tensioner is past the cams. If you spin the chain CCW all the slack pulls out of the tensioner and the timing on the cams (valves) is off, and there will be slack in the chains.

You can back it off a little bit CCW, but not far.

If the crank feels like its hitting a hard stop when you turn it (and you have the bike in neutral - bike rolls freely while not pulling the clutch) then something is mechanically broken in there.
 

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the compression will leak past the rings after a few seconds so it really can't cause lockup, when i turn mine with the plugs in i can hear the air compressing and leaking slowly past the rings, it get a bit stiff but after a couple seconds it turns easy again when compressed air has leaked out
 

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Discussion Starter · #23 ·
the biggest question is how much did a non running bike cost? that should tell you if it's worth fixing, used engines are fairly inexpensive for this bike as long as the rest of it is in good shape you might want to consider it
Another long day at work and no progress on the bike.... Unless you count staring blankly at it while drinking a few beers progress.

So far my non running project bike has cost me:

.01 in ink to sign the title
$25.72 for beer and pizza to a buddy to bring the bike across town for me
$100 for Yamaha brand battery
$35 for licencing fees
for a total of $160.73


The engine sieze test:
When I did the test I had the plugs out I had sprayed some penetrating oil in the cylinders the night before.
After about 20 degrees clock wise movement the enigine hits a hard stop. I had the bike in Neutral during this.

Sorry if i was unclear about how I did it.
So turn engine clock wise 20 degrees to hard stop no compression build ( no plugs for compression)
back off 5 to 10 degree CCW so i could reattempt clock wise movement.
 

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So turn engine clock wise 20 degrees to hard stop no compression build
Sorry to hear that.

I tend to be overly wordly explaining things on here because I never know the other persons level of experience. Besides that other people will be reading this thread someday searching on the same problem, and they might not know anything at all about engines.

I agree with the post above, you can either look for an engine from a wrecked bike or part this one out..

Very often (if you have the time) you can get more for a bike selling the parts than you can for the entire bike.
 

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Discussion Starter · #26 ·
AHHHHHHH WTF!!!

OK so in a part I'm back to square one. I stopped by the bike shop today after work. only to find my bike setting over in the corner NOT being worked on and not on the table where we had it. The Mechanic at the shop, the one who was/is....who is now not going to show me how to fix a bike.

His explanation was that he just finished a bike with the exact problem as mine and it was a nightmare so hes not going to mess with it now. His biggest complaint was that when he opens the top end he has to put it back in time and he says he cant do that. He had three different mechanics work on the last bike and still didnt get it running right. He says he cant put it back in time.......????? He started rambling on about all sorts of gears in there that he doesnt want to mess with. We haven't even opened it up to see what the actual issue is yet.

I have researched a good deal the last week or two on bikes and mixed with my engineering and auto building background it dosnt seem that complicated to get a 650 back in time. Am i looking at this wrong? Is setting the timing really that hard?

I think I'm going to go get my bike back this weekend and I believe I am going to tear the engine down, find whats wrong, and rebuild it if needed myself.
 

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Now yer talkin. If you have the mechanical know how, I say go for it. After all, it's not running anyway. What do have to loose. And in the process, you get to know yer machine. Doesn't sound like that guy is much of a mechanic. Probly better that he doesn't work on it anyway. And it does sound like it could be a timing issue with yours as well. Or something in the timing sequence. But could also be something broken inside. Good luck with your endeavor. Hope it's something easy to fix.
 

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Discussion Starter · #28 ·
OK.... So I finally just got enough time to get my bike home tonight.
I was in such a hurry that I didn't check it out i just rolled it on the trailer and didn't stop until i got home. After getting it unloaded i noticed that my spark plugs and air cleaner are missing. So i called the shop, he says " Yeah those got thrown out you needed new ones" GREAT! I know i just got my bike but after leaving it at that "shop" for the last few weeks i feel like i need to wash it, give it a hug, and ask it where the bad man touched it, and i haven't even got it running yet. Then he goes on to tell me that now the only problem is it jumped time and that i need a professional to put it back in time, one that knows V Stars and it'll magically be fixed. ISN'T HE SUPPOSED TO BE A F*&#ING PROFESSIONAL?!?!?!?! I guess i got confused by the 12 foot wide YAMAHA banner on the outside of his building.

OK that rant is over. So I have her home now. I'm going to try and start tear down this weekend. Ill post pics and try to keep everything updated as things progress.
 

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If you can beg borrow or "steal" one of those little inspection cameras and look inside the spark plug holes, you might be able to see how bad it looks in there.

I have to assume this is an interference engine, which means the things that would be hitting are the pistons into the valves. If the timing jumped or the chain broke while the bike was being run, things will be pretty smashed up in there. Im expecting that is most likely what happened, in which case you have several parts to replace.

again: it would be unusual for a bike with relatively low mileage to jump timing or drop its timing chain. If you look inside and the pistons are pristeen, then it could be something else hitting metal to metal.
 

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something bad had to happen to cause it to jump time, i wonder how he even knew it jumped time when you can't rotate the engine all the way around, i would pull the chain tensioners and see if one them have broken teeth on the plunger or if the pawl broke, if they both are good then a valve probably got struck by over revving the engine, or the valve adjuster loosened up enough to cause a rocker to break locking the top end up by jamming the cam, i'v never seen a bottom end fail on a bike unless it had no oil in it.
 

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Hey everyone. I hate to join the forum with problems, but i'm out of ideas. I searched the forum but I haven't found anything that sounds like whats going on with my bike.


I recently bought my first bike. i have built and worked on cars my whole life but i am just now venturing into building my first bike.

Ok here we go. I have a 2005 650 custom with 23000 miles. I purchased the bike knowing it didn't run. The person i bought it from didn't know anything about bikes either and decided it easier to buy a new bike than fix this one. I am starting to think he was right.

I was told that the bike would not turn over. That was all the information i was given about the bike before purchase.

I have had the bike 3 days now with no real progress.

Electronic start:
I turn the key fuel relay clicks a few times, engine light goes out after a few seconds neutral light comes on. turn signal/driving lights come on (headlight stays off). turn the gas on pull choke, raise bike off stand, pull clutch, press starter button......... NOTHING. No clicks, no pops, no grinds, just nothing.

Trouble shooting process:
Remove starter (not to self buy a drain pan...... and kitty litter bike starters aren't like car starters). jump starter when off the bike starter spins, put back on bike.

test continuity on starter wire to solenoid: test good
test continuity on solenoid: test good, also jumped solenoid starter would not engage while on bike.
replace old battery with brand new Yamaha battery.
test kickstand switch: test good
test clutch switch: test good
test kill switch: continuity test good
test start button: continuity good, jumped: starter would not engage


Push start attempt:
I put the bike back together after chasing all the circuits i could think of. My wife helped me push the bike to the top of the big hill beside our house..(note to self check on wife laying in the ditch almost to the top of the hill).
turned the key on, gas on choke out, 2nd gear, clutch in coast to 10/11 mph, release clutch.... The back tire locks up and bike skids to a stop. The engine never attempted to turn over.
tried everything a second time in 1st gear with the same results.

side note/question
when the bike is in neutral it will coast/roll easily
when the bike is in gear with the clutch pulled in the bike feels heavy/hard to push.
when in gear and clutch is pulled on the hill the bike would not roll unless pushed
after a short push it will start rolling easier.
Is this normal with bikes?

I am completely out of ideas. I really want to fix this myself but I am at a loss. Is it time to take it to the shop?
Thanks in advance for any help.
There is a red switch above the starter button switch it down and try to start it
 

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OK.... So I finally just got enough time to get my bike home tonight.
I was in such a hurry that I didn't check it out i just rolled it on the trailer and didn't stop until i got home. After getting it unloaded i noticed that my spark plugs and air cleaner are missing. So i called the shop, he says " Yeah those got thrown out you needed new ones" GREAT! I know i just got my bike but after leaving it at that "shop" for the last few weeks i feel like i need to wash it, give it a hug, and ask it where the bad man touched it, and i haven't even got it running yet. Then he goes on to tell me that now the only problem is it jumped time and that i need a professional to put it back in time, one that knows V Stars and it'll magically be fixed. ISN'T HE SUPPOSED TO BE A F*&#ING PROFESSIONAL?!?!?!?! I guess i got confused by the 12 foot wide YAMAHA banner on the outside of his building.

OK that rant is over. So I have her home now. I'm going to try and start tear down this weekend. Ill post pics and try to keep everything updated as things progress.
Did you ever find out the problem and fix it. I just spent the last 15 minutes reading the whole thread and I don’t even want to risk getting a used bike of the same model that also doesn’t run currently haha. I just wanna know what happened with yours. This story must not go unfinished haha
 
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