1972 Triumph Tiger (650) Full Engine Rebuild
Here we have a 1972 Triumph TR6R in for a full engine rebuild! Everything will have to be completely dissembled and thoroughly cleaned and checked. The Main Roller bearing is suspect to be the problem. As most engine rebuilds go, you always find (and see) little corners that the previous owner(s) "cut". Initially the bike ran great but started to develop a bottom end rumble. Very unfortunate as it was a very sweet runner. Follow this blog as we will update it weekly!
Cylinder head from 1971-1972 have many differences from the previous and earlier years. Studs with Allen heads can be seen to securely fasten the cylinder head down with adequate torque.
Cylinder head & Barrel look to be in great shape. Behind the right cylinder on the case there appears to be what we thought was a surface crack but is indeed a crack, but nothing severe. Sometime in the Tigers life it threw a rod and luckily the intake cam took most of the damage saving the case. The case will have to be repaired especially on the inside as the previous owner/mechanic decided to use J.B. Weld rather than having it welded. Little particles of J.B. Weld & gasket sealer floating around in the crank is not a good thing! One of the corners "cut" I was referring to earlier.
Notice the timing gear thread size on the wheel as they are different from the earlier years. A special tool or puller must be used.
The RHP MRJA 1 1/8" roller bearing inner race appears to have much wear.
Cleaning the cases we simply used a brass brush and allowed the cases to sit in a tank cleaner. There are many options to clean cases such as vapour blasting, sand blasting or soda blasting. I highly recommend vapour blasting over sand or soda blasting as vapour blasting is non-abrasive and keeps the original texture of the cases. Using a soft brass brush is an excellent non-abrasive alternative (affordable) to clean it up without any damage.