XR650L Valve Noise

[WY XR650L]

I have a 1999 XR650L with 3700 miles that has started to make a loud ticking noise. I road it 150 miles last week and when I got home I really noticed this new noise. I bought the bike with 2500 miles on it three months ago and it runs good. I checked the valves after the ride and found the right exhaust valve had .040" clearance, the lock nut was tight. It still makes a loud ticking after the valve adjustment. I researched the TT site and went back and checked the valves again and noticed a loud tick when turning the crank counter clockwise to find TDC. More research shows it has an automatic decompression release and I'm sure thats whats making the noise, any ideas?

[WY XR650L]

I pulled the valve cover off and found the cam and the rockers worn. The rockers on the exhaust valves were worn to a concave shape. I ordered parts and will let everyone know if that was it. All else on the top end looks good. The bike sat for a couple of years and who knows what happened in the previous 6 1/2 years.

[frankieo]

I also had the same problem with the right exhaust valve. The rocker would move almost an 1/8" when on TDC, all other valves were perfect. I pulled the rocker cover to inspect & did not look too bad. also pulled the cam out because I thought the decompressor cams felt loose & causing my play in the rocker.

I took the cam & decompressor coms to the dealership, & they said thit was ok, with minimal wear. the valves do not appear to be bent either...... I just don't know where to go now ?

Thanks for any help

Frank

[wobblylegs]

I have a 95 that showed the problem with concave rockers. It started with the ticking noise and then slight loss of power. I changed the camshaft and rockers out. Rode 150 miles and same thing. I had missed the real problem. The oil pump was bad and not suppling ENOUGH oil to the top end. It was getting some oil and this is what threw me off. Hope this helps.

[WY XR650L]

Thanks for the reply. How many miles were on it when you changed cam etc. How did you determine it was the oil pump? I ran mine at idle with the valve adjuster covers off and it seemed like there was plenty of oil.

[WY XR650L]

I have just purchased the parts to put my '99 XR650L back together, cam, rockers oil pump, gaskets and o rings. I bought Honda synthetic 10-40 with out moly and needed a suggestion for cam lube. The factory service manual calls lubricating the cam and rockers with motor oil. This will be the second cam and rockers in 300 miles and do not want to take any chances when putting it back together. I suspect it is a lubrication problem and did find the hose from the frame to the oil pump/crankcase twisted. I hope that is the problem. The bike only has 3500 mile on it.

Thanks

[rebelventurer]

Welcome to TT, hate to see you having this sort of trouble. My 04 L has 11000 miles on her (none easy either) And still runs perfect, have checked the valve clearance numerous times and have never needed adjustment to date, I guess I got one built on a good day (thank you Honda) Oil is the lifeblood of these motors, both a partial coolant and lubrication, change it often, use a weight of oil for your ambient air temp, I have used belray thumper oil for the last several thousand miles and really like the stuff, its a semi synthetic and I get by the gallon for around $15 ea. 20w 50.

[creeky]

I also had the same problem with the right exhaust valve. The rocker would move almost an 1/8" when on TDC, all other valves were perfect. I pulled the rocker cover to inspect & did not look too bad. also pulled the cam out because I thought the decompressor cams felt loose & causing my play in the rocker.

I took the cam & decompressor coms to the dealership, & they said thit was ok, with minimal wear. the valves do not appear to be bent either...... I just don't know where to go now

Thanks for any help

Frank

Make sure that the auto decompressor is not engaged while adjusting the valves. If the decomp is engaged, the RH exhaust rocker can be misadjusted. An easy way to make sure that the decomp is not engaged is to slowly operate the kick starter until you feel good solid compression, then rotate the engine to TDC and check the valves.

[Kawabuggy]

The auto-decompressor won't EVER add clearance at the right hand exhaust, it will only take away if it is activated either wholly or partly. If you are at TDC and have more clearance than the manual calls for-you need to adjust the valves.

I just replaced all 4 of my rockers, the followers, and the right side exhaust valve, and the cam due to excessive wear and degradation of parts.

My right side exhaust valve was wasted. The tip where the follower touches it was mushroomed. This area appears to be a weak point on these bikes.

[axarob44]

the right exhaust valve needs to be adjusted in a different crank position than then rest.

Can you elaborate on that statement? The service manual says nothing about a different crankshaft position to adjust the right exhaust valve.

1. Remove fuel tank.

2. Remove timing hole and crankshaft hole caps.

3. Remove valve adjusting covers.

4. Rotate the crankshaft counterclockwise and align the "T" mark with the index notch of the left crankcase cover.

5. Make sure the piston is at TDC on the compression stroke. Check the clearance of the exhaust and intake valves by inserting a feeler guage between the adjusting screw and the sub-rocker arm.

6. Adjust by loosening the lock nut and turning the adjusting screw until there is slight drag on the feeler guage.

7. Hold the adjusting screw and tighten the lock nut.

8. After tightening the valve adjusting lock nut, recheck the valve clearances.

9 Install the removed parts in the reverse order.

Am I missing something?