Hi!,
Have you been on this forum a little while? Do you have a shim kit for sale? (even if a few are missing), or would you be interested in splitting the cost of a shim kit?
Hi. When I needed to buy shims I went to some garages in my area. No one volunteered to sell me 4 shims. The guy who did "agree" said that his kit was currently with his friend, and he had not returned it to him yet. The central Honda agency was willing to sell me 4 shims, about 7USD for a single shims. Since I was not pressed for time I eventually purchased the shims online, and it took about three weeks to arrive (When I waited the valve cover was open, and I covered it well!).
The generic shims kits are less accurate (at 0.05 mm intervals), the original OEM shims are more accurate (at 0.025 mm intervals).
A Coordinating Expectations: Honda did not intend that their mechanics adjust the valves when the engine install inside the frame. And evidently, all the explanations in the Honda's maintain service book are with an engine that is outside the frame. At Honda's book they wrote that it is possible to adjust valves when the engine is inside the frame, BUT only in "rare" cases, in a "strange" way, this happens after the end of their warranty
Adjusting valves in CBR250R is a very difficult job, and a mistake can be costly a lot (say: falling shims into the engine, etc ...). I'm not trying to despair you, I did it my self, just saying that ...