Today I was working on a Yamaha DT200 YPVS controller, that belongs to Joel(NZ). This curve opens the exhaust valve at 4.620rpm and the
cycle is completed at 8.640rpm.
If you check the blog post that I did a couple days back, you may notice that Yamaha uses the same closing time for the 125cc model as well. Though the curve starts opening the valve earlier on the bigger capacity bike.
This is something to keep in mind when tuning other bikes as well. It does help to use an exhaust valve curve that delays the opening of the valves on bikes with weak mid range or tuned for higher revs.
I have repaired and modified a YPVS controller for Kire(DEU) and found yet another one YPVS curve that was previously unknown to me and might be a good suggestion for all 125cc bikes, including the TZR125 models. This curve is opening the exhaust valve at 4.800rpm and the cycle is completed at 8.640rpm.