Offset shock bushings can be used to reduce or increase both your bike ride height or to slacken or steepen the head angle. However, I have used one for something completely different. My rear shock was shot (that can happen when you buy your frame cheap on ebay !) and suspension servicing costs are really expensive where I live, so I decided to replace.
The eye to eye dimensions were 215mm, and there were not many options in terms of cheap shocks available on the old interweb. I had read that you can fit the next size up (222mm), if you run a pair of offset bushings turned inside towards the shock itself. I picked up a Vivid R2C shock new from Taiwan on ebay, together with a set of custom made offset bushings (offsetbushings.com).
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