It's not the length of the bones that matter but the distance between the holes, the shorter the distance between the holes the higher the back will rise. Theoretically the 50 mm jack up kit could be physically longer if there was more meat around the holes but the holes should be closer together than stock or a 25mm kit, bearing in mind we're only talking a few mm.
The ones you linked to are similar to the ones I bought (also from ebay) so I wouldn't worry too much. When fitting them use a chock under the wheel to raise it up a bit, that will save you wrestling with the assembly when trying to get it back together, and have some grease ready to lube all the roller bearings etc.
As robbo says it's a really good mod which greatly improves the flickability of the bike through the twisties, it also firms up shock compression which will help a lot if you still have the tired old original. I would say the 50mm kit with the forks in the standard position is about the same difference in handling as the 25mm kit with the yoke dropped down the forks by ~15mm, the first option is better for taller riders the second for shorter. Lowering the yoke with the 50mm kit adversely affected the handling at least for me so I wouldn't reccomend it.
Yup it was RAF Wittering, on a visit to my realtives who live just outside Peterborough, here it is with my uncles blade and the harrier.
![[Image: 50618154767_49f9c6f407_h.jpg]](https://live.staticflickr.com/65535/50618154767_49f9c6f407_h.jpg)
The ones you linked to are similar to the ones I bought (also from ebay) so I wouldn't worry too much. When fitting them use a chock under the wheel to raise it up a bit, that will save you wrestling with the assembly when trying to get it back together, and have some grease ready to lube all the roller bearings etc.
As robbo says it's a really good mod which greatly improves the flickability of the bike through the twisties, it also firms up shock compression which will help a lot if you still have the tired old original. I would say the 50mm kit with the forks in the standard position is about the same difference in handling as the 25mm kit with the yoke dropped down the forks by ~15mm, the first option is better for taller riders the second for shorter. Lowering the yoke with the 50mm kit adversely affected the handling at least for me so I wouldn't reccomend it.
Yup it was RAF Wittering, on a visit to my realtives who live just outside Peterborough, here it is with my uncles blade and the harrier.