cam chain probably jumped help please

[guncelf]

Hello,
Today I was riding my 2001 GS 500 when I heard a loud ding sound and then I started hearing my cams working really loudly. So I stopped and looked on bike what happened. There I found  my cam chain tensioner bolts got loose by and fell down  which shot out tensioner spring. Then I started my bike as I had only 2 km or 1,2 miles home. The sound of cams was really cool but after about 1 km of very careful ride my bike turned off. I tried starting it but it just made dinging noise. I had to push it for 0,6 miles home. There I put chain tensioner back at its place. Engine got silent again but it wont start. Starter turns engine over very easily and fuel is being delivered to pistons but nothing happens. I suspect that cam chain jumped and theres no compression, if so I hope that my cams werent bent or that theres no other damage. If you had similiar problem or can help then Thank you very much.

[The Buddha]

Wow, OK then. Your cam chain tensioner is dead and you decide to ride home ? so The $50 for a tow is worth more than the $500+ for a motor ?

First law of riding a bike. Hear weird noise, turn the frucker off. Matter of fact, it might as well be the law of anything.

Cool.
Buddha.

[Bluesmudge]

You are going to have to start by taking the valve cover off and see what's going on. Very good chance that things are f@cked beyond repair. As soon as the cam chain tensioner released, the cam chain could have easily jumped off the cam sprockets. At that point all bets are off for how bad things can get.
Chances are...either:
1.) Chain jumped off a sprocket, bound-up, and broke...thus sending hardened steel bits everywhere.
or
2.) Chain jumped a tooth, timing went off...bent a valve (or all 4) and thus no more compression.

If you are lucky...the chain is still sort of on the sprockets and its #2. That could be fixed with a top-end rebuild.
If its #1...you are SOL and probably need a whole new engine.

[guncelf]

Damn at that time I didnt even know it was cam tensioner it just looked very weird Im gonna give it to mechanic and hope it the repair wont be more expensive than the bike   

[The Buddha]

Damn at that time I didnt even know it was cam tensioner it just looked very weird Im gonna give it to mechanic and hope it the repair wont be more expensive than the bike   

No, find someone near you from this forum and persuade them to look at it. The mechanic will cost you more than the bike is worth, and that is if its just the cam chain tensioner. You jump a tooth, your motor would have banged itself up too much to be worth it at all.
Cool.
Srinath.

[Bluesmudge]

Yeah, where are you located? If you are near Portland Oregon I would help you diagnose the extent of the damage before bothering with a mechanic. I'm sure many other GStwinners across the globe would do the same.

Mechanic around here would charge $150 just to tell you what is wrong. To actually fix it they would charge $1k - $2k (assuming it is repairable)
May actually be cheaper to buy a running engine for like $500 and pay a shop $500 to swap it in or learn to do it yourself.

[guncelf]

Thanks but I live on the other side of planet (Slovakia). Now Im working on it and for now I know that just valves are bent. I dont know how many or which ones but I will give it to mechanic with new valves from our local ''craiglist''.

[The Buddha]

You can check and know what valves are bent.
Take off carbs, exhaust and sparkplugs.
For good measure take off the valve cover as well.
Put the motor where one cyl is @ top of TDC.
Shine a flash light in intake - better to do this part on a dark night.
If you see light in the spark plugs hole lighting up the chamber - intake is bent.
Shine in exhaust - if chamber is lit up when viewed through spark plug hole - exhaust is bent.
Repeat for other cylinder.
Translate to Slovakian and give to mechanic if you're taking to mechanic.
Cool.
Srinath.

[guncelf]

Thank you, thats a great idea

[The Buddha]

Put the motor where one cyl is @ top of TDC. - Well TDC at top if compression stroke - not @ top of exhaust stroke - just use common sense.

Cool.
Buddha.

[guncelf]

update
I removed cylinder head and dicsovered that both exhaust vallves were bent. Intake ones seemed ok, I even poured gas on them when they were turned over and looked for leaks, there were  none. It seems that if I replace those exhaust ones I will be able to make it work. I would also like to put pictures here , but I dont know how.

[guncelf]

There it is
https://imgur.com/a/VsDCtao?fbclid=IwAR068I89Mi08hnzFg9VcmtE9iIiZOcq0LmoWvJN9ISUnIIEUaR1TlaqjfiE

[The Buddha]

The bent valves are visible only from the chamber side, not the cam shaft side. BTW you check valve clearance before pulling off the head ? Bent valves will show a huge increase in clearance.
Cool.
Buddha.