You always hated it when it happened and it feels even worse when it happens between motos. If you want your carburetors to work nicely and well tuned then you should use a proper coupler. WatCon zero backlash carburetor shaft coupler will not compress after age. Coupler is 35mm total length. Call or log in to WatCon.com to order yours at the price of $50.00 usd.
