The U.S. importer sent an e-mail to Inntek regarding Gas Gas parts, here's their response,,,,,,,,
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The most valuable parts are the following:
600.010.004 - Chain tensioner blocks
600.011.000 - Rear red sharkfin with black caliper support which offer
also support for chain tensioner block for rapid rear wheel swap.
600.039.001 - Rear chain guide
600.048.004 - Shock Linkage ("dog bones") with adjustable length. This
piece improves bike handling (agility) quite a lot. Very appreciated
by top riders.
600.060.004 - Triple clamps - This is really appreciated by Ivan
Cervantes and improves front stability and "solidity" - Suitable for
SACH or Kayaba suspensions.
350.030.028 - Handlebar mounts for Triple clamp (the same you have for Hondas)
Than there are all the other "cosmetics" parts like various set of
screws, sprocket protection, etc etc etc
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