Monday, May 5, 2014

Triple clamp swap from CB750 to XL500S

The reason I am installing CB750 triple clamps on my XL500S is to allow installation of a wider front wheel (wider rim & hub). The fork tubes are 20mm further apart to allow for this, but still accept the original 35mm fork tubes as they are common to both bikes. The CB750 stem needs to be removed as it is too long for the XL500S steering head. The CB750 stem is welded into the lower clamp and is also an interference fit. The above pics shows that the weld has been removed and the stem is starting to come out.
This pic shows the correct size socket being used as a drift in order to knock out the old stem. This requires a large hammer and a little patience. It eventually comes out!
This pic shows the old stem, spacer and lower bearing seal as they have come apart.
I have a spare stem which I have removed from an XL250S. This stem is clamped and glued in place, a large hammer and some patience is required for removal.
This pic shows the XL stem in the CB triple clamp. It is quite a loose fit, so some shims need to be installed to take up the slack, the stem is 27mm diameter and the hole in the clamp is about 29.5mm.
Lastly the stem needs to be fully welded to the lower clamp, as this pic shows. Once the lower bearing race and seal are reinstalled you are ready for reassembly.