| Theoretically as horsepower and sticky wide tires are added, the stock frame is unable to cope with the additional stresses. Starting with a photo of the stock frame as we know it: |
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| Modifications proposed in a sketch by "Team Incomplete". The traditional faults of the stock configuration are addressed. Neck stem and swing arm pivot points are connected by bracing to maintain alignment: |
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| As the "Team Incomplete" frame turned out. An extreme amount of triangulation is used and the lower frame rails eliminated. The engine is hung from the rear mounts, the upper trans to case bolts, and an added mount at the upper chaincase casting, about where the diode board normally resides. Gregor Halenda claims that this frame is lighter than stock: |
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| The preeminent frame builder, Rob North, started fresh with this design. Rob North earned his reputation by crafting frames for such racing legends as Dick Mann, Dave Aldana, and Gene Romero. Apparently the BMW rendition was more successful in a twin shock version: |
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| Rob North built a similar chrome-moly frame for the 745cc BMW GP bike campaigned by Butler&Smith, and ridden by Reg Pridmore. Rob North's frame deserves a couple of pictures: |
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| And some details: |
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| More details: |
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A sketch of the proposed "XRS2 / OLD CRO Chassis". Yes, the method in my madness – researching a frame-build of my own. The design incorporates a modified stock frame ( as used by racers since the 70's, and vintage racers today ) with a good dose of Tony Foale, just a dash of Incomplete, and lessons learned from Rob North.
Randy Illg at FRAMECRAFTERS has agreed to craft this design, and construction has begun. Pics of progress are on the "Old Cro"project" page. |
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| This rolling chassis was a kit marketed by CC Products. Apparently it never went on sale due to liability issues. Too Bad. Heard there may be a few prototypes around. |
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| This frame is one sold by HPN. although designed for GS type usage, and not road or track work, it does indicate weak links in the stock unit when put to extreme use. Neck stem and swing-arm pivot areas are reinforced with plate (areas in grey) to eliminate potential breakage: |
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