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I guess you had already removed the cam chain tensioner before you loosened the bolts??? That doesn't work too well.
Yes, you have made the job more difficult. Be patient....good luck.
 

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Sorry for your woes. I have read of other members with similar problems. I think there is a reference to using helicoils to repair threads. Keep at it!
 

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Discussion Starter #43 (Edited)
Yahoo! Finally got all the cam bearing cap bolts out. All of them needed the use of an air impact wrench. Unbelievable! The 5 mm hex rounded a lot of the bolts. Using a ball peen hammer to peen and tighten the socket helped. Torx bits were useless and just bounced out of the bolt head. The only good thing about them was that they helped open the bolt head up to fit the next size allen key. 5.5 mm hex hammered in and air impact wrench worked on some bolts. I think hammering the bit into the bolt head helped loosen some of the bolts. However on a couple of bolts even hammering a 6mm hex into the head and using the air impact wrench just resulted in further rounding of the head. Of course they were 2 of the recessed bolts. A friend who has a welding business said he couldn't weld a nut on as it was all too small and the nut would just fill with weld. Started to drill the bolts out hoping I could avoid the magnetic attraction between aluminium and drills. Bolts just laughed at my HSS drills. Got some high cobalt left hand drills which didn't do much more. Finally got out carbide tipped drills and ran the drill flat out on hammer setting and it gradually chipped away at the bolt heads. Drilled most of the way into the bolt head and tried hammering a 1/4" bit in. This time the bit was far enough into the head that the air impact wrench loosened the last 2 bolts out. Gradually loosened and removed all the bolts and bearing caps. All the threads seem ok but bolt heads unusable. The pressure from the valve springs was nothing compared to the bolt tension. Tied up the cam chain and removed the cams so that the I could turn the engine over and align the crank timing marks. Now I can finally adjust the valve shims. Apologies for the length of this post but I thought it maybe useful to share my mind-boggling experience compared to other similar threads.
 

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Congrats on getting them out !!! You had a real battle there !!!
 
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Discussion Starter #46
Fortunately local bike dealer had a good selection of shims. Vernier caliper didn't provide accurate measurement so I invested in a micrometer. Then had to wait 3 weeks for new cam bearing cap o-rings to arrive from MV Australia. Used Noel's directions to lock crankshaft but locked it to another bolt hole so that I could still see the timing marks.
Then installed camshafts and locked inlet camshaft as per Noel's directions.
Rotated the exhaust camshaft to get the mark on the 24th chain pin as per manual. Applied tension to the cam chain with a cable tie as per another forum thread I've lost and installed the tensioner. The chain seemed tight and the cams weren't sitting in the bearing holders properly so I slowly rotated the crank and gradually tightened the cam bearing caps down. After the problems I had getting bolts out I used "Neverseize" on the new ones and torqued to 12 Nm which is approximately equivalent to 18 Nm dry. Engine rotating OK and timing seems right but chain still seems tight. Rechecked clearances. Couple of exhaust clearances a bit looser than spec but I don't think its worth dismantling again. Installed valve cover with high temperature copper silicone as per forum threads. Now just to put the rest of the bike back together and test.
 
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