Answer Manitou 4, 3, Comp Suspension Fork Elastomer Set

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Replacement TPU based elastomers for the Answer Manitou 4, 3, Comp, Magnum, plus other Manitou aluminum front suspension forks from the 1990s. These are designed to replace the original elastomers that have long deteriorated and broken down into goo over time. The Manitou 4 uses 6 compression elastomers and 3 rebound/2nd stage elastomers per fork. Other models use the same counts or other combinations of compression elastomers. TPU will have similar compression and rebound to the original elastomers. A controlled rebound being the important factor so the fork doesn't feel like a spring. After many rides with these replacements, the fork has felt good like the originals.  Print with the following filament and settings: TPU filament with a hardness of 90A or 95A has had good results. Over several months of riding the TPU elastomers have maintained their original size to within about a mm.  Infill pattern: Gyroid. This has excellent strength and compression characteristics. The infill density will determine the overall suspension softness, how much force is required to compress each elastomer: 30% : Soft 35% : Medium 40% : Hard Print using a shell wall thickness of zero. An exterior wall will not allow the elastomer to compress well and will end up buckling. Use 4 top and 4 bottom layers. Start with 35% infill initially for the compression elastomers, this seems to be good for riders around 170-200lbs. Additional harder or softer elastomers can be swapped out to fine tune the overall stack based on weight. Print the 2nd stage / rebound elastomers with a 25 - 30% density so that the end of travel has a soft landing. Softer TPU filament than 90A can be used, infill density will need to be increased or even set to 100%. The elastomer needs to be firm enough to support the proper weight of the rider without continuously bottoming out.  The guide rod that holds the elastomers should be greased, but be cautious of the type of grease that is used. TPU is generally oil and grease resistant, but because the exact properties of TPU filament are not always known, certain greases may degrade the TPU. Use a grease that is generally safe for plastics such as a silicone based grease.