Another GPZ FF - gets a new rear end
Last September I had a shake-down run to Monty's place in York, across to Kirby Lonsdale and home. Apart from learning a few things about chain maintenance, that trip reinforced the need to sort the rear end. To make space for the lowered seat, the rear wheel had been moved back. This was done by adding bolt-on swingarm extensions. Extending the swing arm messes with the suspension, so it felt a bit soggy at the back. The effective spring rate changes with a square rule, meaning that the response time to any bump was loooooong.
I could have changed the original coil-over-shock unit, but that wouldn't have addressed the issue of flex in the swing arm. So, as suggested by Jean-Marc and Arthur, I added supplementary units mounted at the rear. The units I chose are from an X9 (or possibly and X8). In themselves they are not big enough, but combined with the existing unit, they seem to be ok.
In addition, I added Royce's 'Hippy Handling Helper' (otherwise known as a rear wishbone) - you can see it in red. This deals with any possibility of the long arms moving independently.
Here are the before and after pictures minus the top box (which obscures all the interesting bits)