Product Description
Centre Shaft and crank seal set, for all the KR1/KR1-S cranks.
Worn crank centre shafts and seals are a common issue with the KR1 / KR1S model. It is critical to have the correct surface hardness and correct surface finish for seals and the shafts to last, this has to be between 0.2 and 0.25 Ra. This is the reason the shafts and seals wore very quickly on the originals.
These centre shafts have 0.005mm more intrference on the bearings so that they won't slip on the shaft any more, and the fit into the webs is slightly tighter as well.
Please note that due to lack of availability the original timing side seal has been replaced with a non-castellated seal. We have supplied and used this seal on a good number of engines and so far no complaints. The castellations are only to space the seal correctly from the main bearing but the seal has a lip and there is a groove in the case to locate it correctly anyway.
Photos display an example of a worn crank pin with grooves where the seals run and polished where the bearings have been spinning on it - fresh seals would appear to cure this temporarily, but it wouldn't last long and you'd be up for a fresh engine rebuild and seals again.
Photos also show a couple of pictures of the fresh crank pins which are seriously harder wearing than the discontinued originals.
