Sphynx 300 from led

[Anthony0327]

So I've been back an forth on what I want to do motor wise. Ive read a lot of threads about so many different motor setups. Where I live there's a little bit of everything to ride, trails, sand, etc. I don't need to be the fastest guy out but want more power than what a stock 250r has to offer. I was looking into having led do my motor with the 300 sphynx. Is there anyone on here that has this setup? Just want some opinions and reviews if possible. I want something reliable with power that's fast. Chances are I will only do a build like this once so I want to make sure I get something that impresses and of course is reliable.  Thanks in advance for your replies.

[christph]

I'm also in the market for a new cylinder and am interested in feedback on the Sphynx 300.  From my own research I understand that the Sphynx cylinder is the best out there (it has a modern port layout and a Nikasil bore) but it is also the most expensive by far.  To save money--nearly $900--I've considered going with a Pro-X 330.  I'm pretty sure a Sphynx 300 will out-perform a Pro-X 310 but not a Pro-X 330.  Another possibility is the Sphynx 350 but then you will have to bore the cases.  Normally I would get the 350 but I'm putting it in my 86 ATC and I don't think my Paul Turner pipe will handle the displacement, and I'd rather not have to buy a new pipe too.

[etccb]

There is no replacement for displacement. Sure a 300 will run nice but if you want to do this build 1 time and leave it for a long time you should think about doing something a little bigger maybe with a 4 mil stroker if you are going to be having your engine cases apart. There are many reliable options out there if the install is done correct.

[Tbone07]

It mostly depends on how much money you have, and how much power you want to make

If you want to cut costs and still go to a big bore you could always have your builder of choice use an ESR cylinder

[JesseA420]

i would call and talk arlan if that his who you are going to use to build, see which route is the most cost effective for the application you need, there are an infinite amount of motor combos. if you want to go budget route with bolt ons so you dont have to split cases but still get the most bang for your buck, send arlan a esr 330 bolt on builder kit and have him set it up for you, i would think your pipe would be ok without needing to go to a big bore pipe. also the new esr cylinders have a new port layout and are much better than previous versions. only downside is since it doesnt require case boring you get a couple less overbores due to the thinner sleeve.

[The_Steve_Man]

I do the same exact riding and I talked to Arlan about the exact same thing and he suggested to get the ESR 310 builder and send it to him to do the work. He said the shynx is about $700 more I believe.

[rsss396]

you cant go wrong with what Arlan suggests, but if you decide to go with a sphynx, I suggest you go with a ESR piston.
The CP pistons, or at least the ones with a 78mm bore do not have the ring ends in the correct location and in both sphynx I have built the rings are prematurely wearing as I expected.  Arlan told me he has not had issues with this but like me does not like there location. But ask Arlan about this because possiably the smaller bores are OK. I complained to CP about the location and was told they would order 78 bore pistons just for the sphynx, the problem came from the fact that the 78mm puma works perfect with them because of the port layout but on the sphynx the ring ends pass over the open rear transfer ports.

To run a ESR piston you have to run a 3mm spacer plate and extra gasket which always sucks but its worth it to fix the ring end problem until CP gets the new batch of pistons made.

[udontknowme]

i dont meen to cut in but does any the cp jugs use 89mm piston ?

[rk88r]

Op I believe the the 300 sphinx needs the cases bored also.

[Jerry Hall]

.........................Normally I would get the 350 but I'm putting it in my 86 ATC and I don't think my Paul Turner pipe will handle the displacement, and I'd rather not have to buy a new pipe too.

The displacement is not the only thing that determines what pipe will work best with the big bore cylinders.  The Paul turner pipes are made for OEM 250 Honda cylinders that have a much different port layout than the Pro-X, ESR and Sphynx cylinders.  All three of these manufactures have totally different port tunnels, different shaped ports and port timings.  

There are different pipes that are best suited for each of these different brands and sizes of cylinders.  The unfortunate thing is there is not much of a selection of pipes for the ATC 250R.  Your Paul Turner pipe is not a good choice for the 330 and 350 cylinders.  If the 300 or 310 is built to make some serious power and you are not using it exclusively for drag racing, the Paul Turner pipe may cause piston overheating problems.

[Pumashine]

i dont meen to cut in but does any the cp jugs use 89mm piston ?

Only mine, the Sphinx was designed to run a 78mm piston. I'm not sure under bores like 72mm are available. Puma is designed to use the 85mm piston and the Saber A 95mm piston. We went to advanced sleeve and had them make an 89mm sleeve for the 95mm bore of the Saber

[udontknowme]

give me some details. is it a cr5 piston or something special ?

[Pumashine]

give me some details. is it a cr5 piston or something special ?

The builder says thats :topsecret: BDT does not have a clue and were all gonna keep it that way.

[udontknowme]

didnt you say you had yz490 rod ?

[udontknowme]

dont want none of your secrets. just looking for a alternative cr5 piston with 20mm pin. wasnt sure if there was something out there or not