ESR 310 Question

[RMS250R]

I have an 89 250R with +4 mm stroker and I am thinking about and ESR 310 Kit if I buy the .25 spacer plate do I still need them to do port timing?

[siderbox]

Just changing the spacer will not do the trick.
You need a jug that is ported for a +4 stroke.

If you have a jug that is ported for a stock stroke.
The spacer will only get the piston to port timing set for either the tdc or bdc.


The piston is not only going up further, higher tdc. It is also going down fruther, lower bdc.