When the bike wouldn't start (20k kms) I thought I'd better check the valve clearances (4 valve head) R exhaust 4 thou (.10mm) shd be 5.5 thou to 9.1 thou (.14 - .23mm) L exhaust 5 thou (.13mm) R inlet 7 thou (.17mm) shd be 3.9 thou to 7.5 thou (.10 - .19mm) L inlet 7 thou so the exhaust clearances are just under the minimum and the inlets are approaching the maximum. Because it's buckets over shims I'll have to remove the cams to put in new shims and I am not keen. Given the present clearances and the fact that the bike is used at low revs on gravel roads, would it be safe to leave the shim replacement for another 5000kms and then check. Maybe I could get away with just doing the exhausts If the shims do need replacing, then I need a chart to determine what size to order. Where can I find this for the Sherpa. Your thoughts
The exhaust valve clearance is too small now, need's to be fixed, inlet's are fine Ask around at a couple of bike shop's to see how much they'll charge to do the work, maybe someone here can help ?
Generally you can fabricate (or sometimes buy) a tool to allow you to change shims without removing the cams. The shims sit in a recess in the bucket and you depress the valve spring and get the shim out... easy enough to get shims to suit.
I can do the shim change for exhaust if it's a must do - just a PIA if you are used to screw and locknut and will get someone to check when i'm finished.
Yes, with the BMW K100 you can change sims in situ, using a bucket depresser tool but that's because the shims sit on TOP of the buckets. With the Sherpa the shims are underneath and the manual says that you must remove the cams. Expected to see marks on the chain at TDC (firing) but there are only marks on the cam sprockets so I'll mark the chain. Have found the chart to calculate new shim size.
Are there any inhouse specialists who have worked on the cam chain adjuster on the KLH. P 70 of the manual says to reinstall the tensioner body ( i would presume with the toothed arm well retracted so that when you do up the body securing bolts, you don't stress the arm and put too much pressure on the slipper.) and then insert the spring and put on the cap. The arm is a non retracting type so once it's extended, it won't come back. I did this but the chain seems like a violin string between the two cam sprockets - very tight. Seems unbelievable that the little spring can do this. I've turned the motor over slowly and it seems OK. Any ideas?
