Couple questions about R motors

[Creech52]

First what is the best year for the bottom ends, the 85-86 cases are supposed to be thicker on the bottom, but does that do anything? Im going to be building a motor soon and was wondering which year bottom end is the best. Second who makes the best PV top ends? I was looking into the ESR but they dont offer a generic or match port option, and Id rather have someone else do the port work as ESR tends to do hit and miss port jobs from what I hear.

[C-LEIGH RACING]

ESR, CT Racing, LRD, & LA Sleeve/Pro-X all have the Pro-X 250R cylinder kits.

The 85/86 engines were bad about gears busting easy.
Yes the 86 cases are thicker & better to use if your intending to build a stroker engine, more metal in the crank area for rod clearance trenching.

Most everybody that knows R engines will say the 89 model engine was the best, but I like the old 86 model transmission gear ratios when building a big bore grunt engine, but they bust easy.
Neil

[Creech52]

So would it possible to just buy a 265 or 310 PV top end minus the portwork and cylinder head and such, just the piston and jug with the PV.

[C-LEIGH RACING]

I dont know if either place would sell just a jug & piston, then again they might.
I do know that you could get the cylinder kit unported from LA Sleeve, but LA dont have the PV valve itself, they have the kits are machined for the PV, no valves though. They use the CT Racing valve assy far as I know.
ESR & CT have their own made valves now & no longer use the Rotax valve assy.

The ESR valve to me is junk though, opens too soon in the rpms & make the engine feel like a drag engine so why even bother building a PV cylinder.

You do know I'm a dealer for ESR, CT & LA Sleeve, right.

You asked without the head, you have a Pro-X head already.
Neil

[Creech52]

I have nothing right now, just a rolling frame. But I want to build a PV motor. They guy im buying the frame off of has a PC2000 top end hell sell for 800, it needs some work tho, either a rebuild or a new bore, comes with all the stuff tho and a few diff. size domes. I just want the best bang for my buck and the best power, without spending a TON of money. I mean if you could set me up with a good package with a PV, I may look to you when it comes time for the motor build.

[C-LEIGH RACING]

You have a bottom end with the roller & how much is that PC2000 messed up, what bore is it 265 or 345.
Neil