Clackety clack engine

Hello all.
Am new to the site, and apologies that our first meeting is with a bike problem. My poor pig is stuck in France in a barn.
Did a trip from London, got as far as the south of France, bike ran perfectly all the way. Checked oil regularly, all was well.
Started the bike on the 3rd day and engine was really clacking hard from the head.

Checked the valves, were way out, inlet had about 4-6mm clearance! Adjusted everything to spec, changed oil and filter (no particles anywhere), loud clackety sound is still there.

Have noticed that when trying to kickstart, the smoothness up until you hear the click of TDC has gone. The stroke is clumpy, but it still starts fine and runs, but with this very loud clackety sound.

Took off the valve covers and turned the engine round quickly from the flywheel, seems the loud click is coming from the rhs exhaust valve rocker. As the rocker comes up shutting the rhs exhaust valve it's like a metal clinking.

Not sure if its a sign of rocker damage or cam or valve spring. Engine only has 3500miles. Didn't want to risk riding it in case it seized.

Any advice would be very much appreciated. Need to arrange to go pick it up next week in a van (I live in Amsterdam), really want to get it back in tip top shape so I can plan my next trip.

Thanks all in advance!

Hello Dutchman

I cant help ya with that problem because im still a noob with XRs.
So i hope you can fix it good and cheap and let us know what it was pls.

greets from Emmen

Thanks mate! Ik zal u vertellen wat ik vind! My dutch isn't very good, but improving. rgds

Does your engine soud like the bike in this Youtube Clip:
http://www.youtube.com/watch?v=GubUPbch-84


Can you post pictures of the valve stem and the contact pad of the rocker arm?

What is the condition of your cam chain and cam chain tensioner?

Is the decompression valve properly adjusted.

The auto decompressor system is mounted on the camshaft. To set the valve clearence on the righthand side valve lifter (this lifter operates the decompressor system) you have to make sure that the system does not work but that is difficult to see. The system is a kind of camlob located next to real camlob. So if the engine is not running or running below 500 RPM a spring pushes this, shall we say fake camlob, outside with a small spring. So when you start or are below the 500RPM the right hand side valve opens and closes in the same way the normal camlob opens and closes the valve. But because this fake camlob is a bit higher on the bottom side then the normal one the valve stays a bit open. When the engine starts running and is coming above about 500RPM the system is pushed back due to the centrifugal forces in its say normal position so not lifting the rockerarm. This sytem normaly works perfectly but after some years it can be blocked.
So to come back for setting the valve clearences on this rockerarm you have to make sure that you have the camlob in a position that the deco system is not lifting the valve. Remove the sparkplug and rotate the engine with your kick starter and just feel when the valve clearence, only for this valve, is the most and than adjust it to the right value. So the TDC point with all the camlobs facing down is nine out of ten not the best position.
The decompressor handle on your steer is lifting the same valve as above but then in the manual mode

Adjust the XR650R Valves


Checking and adjusting the valves on the XR650R is a simple procedure. Here is how.
Remove the seat and the tank from the bike to give you access to the top of the engine.
Clean around the valve inspection covers so there is no loose dirt.
Remove the valve inspection covers.
Remove the large left side engine cover to expose the flywheel and timing inspection marks.
Rotate the crank counterclockwise using the large bolt on the flywheel. Line up the “T” mark with the small notch at the top of the housing.
Wiggle the valves with your fingers. If they wiggle a little up and down then you are ready to check and adjust them. If there is no play in them rotate the crank again, match up the “T” and check again. The goal is to adjust the valves at Top Dead Center on the compression stroke. At this point all four valves will have wiggle in them.
One by one insert feeler gauges between the valves and the tappets to check clearance. Intake valve clearances should be 0.15mm +/- 0.02mm (0.006in +/- 0.001in) and exhaust valve clearances should be 0.20mm +/- 0.02mm (0.008in +/- 0.001in)
The feeler gauges should have a slight drag when slid between the valves and the tappets.
To adjust the valve put a closed end wrench on the tappet nut and crack it loose. Use a screwdriver to adjust the tappet up or down to increase or decrease the clearance. Once it is in the right position, tighten down the tappet nut to hold it in place.
It is often a bit fiddly to get the tappet set perfectly. It will sometimes spit itself a little bit when tightening down the nut. You’ll get the hang of it quickly.
I prefer to spin the engine over a few times then recheck and verify all the clearances.
That’s it! Put the valve inspection covers back on. Put the side cover back on. Put the seat and tank back on.
Go riding!

Yo Rebenga,

with your bike so far away from de Wallen I'd say do this:

- take the decompressor-cable off - off the lever on the head that is, and check if it fully returns under its springload. If it does goto next point, if not find out why not - and I bet you'll find the actual problem then.

- if the above is not the problem you'll have to dig deeper. The often-mentioned "auto decompression system" first of all is a ridiculous misnomer, it does nothing of this kind! This system ONLY comes into action when the crank REVERSES direction, ie when you turn it backward or, the real reason it's there, when the engine backfires! This is a 650, it'll break your leg when it backfires, so, to prevent this, Honda built-in this system which will lift hence open 1 exhaust valve (the left one) when the engine turns backwards, thus relieving any pressure into the exhaust. Obviously this will prevent bone-breaking forces on the kickstarter.
As a side-note: only the std cam and the hrc-copy cam (ground from a std cam!) have this system on, the so-called hot cams do not have it - which, therefore, are potentially dangerous cams!!!
As a result of this system adjusting the valves is a bit tricky - when busy with this NEVER turn backwards, not even for 'just a very little' as it will lift a valve, but only turn forward. You missed the marker? Turn forward again, never ever turn it backward.
Assuming you know all this I take it you are sure you followed the correct procedure for checking the valves? If so, then the next step is to take the entire valve-rocker cover off (het hele klepdeksel).
You will not upset any timing or misalignment, you can do this safely, putting back ditto.
With the cover off look at the rocker's surfaces, there where they run on the cams - any wear??
Also, the cams themselves, the lobes, any wear there?
If it wasn't the too-tight decompressor cable (first point, above) I hunch this will be your problem, an oilstarvation of some kind, and the cams/rockers are the first to go then.
If that's the case you need to trailer it home, lotsa work & Euros

Keep's informed here as to what you find?

Thanks to all who replied on this and sincere apologies for my delayed response. I'm actually going to pick up the brp end of Feb from the barn in France and bringing it back to Holland. Once back I will dismantle the head take plenty of picks and post for your expert opinions. I will get her running like a Swiss watch again and trailer it down to Italy to blast around the mountains at my parents in the south for a few weeks. Pasta, home made wine and BRP and plenty off road. Obviously first I need to get her running properly so will revert ASAP with all pics and details. I just hope the mice haven't moved into the carb and airbox as they did on another old bile of mine.....
Best regards to all! Ciao