Thinking About a BB

[The_Steve_Man]

Thinking about my next project am wanting some feedback on big bores.
What are you guys using and what would you different if anything.

[havinnoj]

That's an open end question. Why don't you post the kind of riding you'd do with this motor and budget.

[The_Steve_Man]

I would say all around. But let's say low to mid.  
Budget?  Not looking to do it on the cheap but dont need top of line either.

I already have an idea but just looking at all the options.
I already have a bike that I am going to use to race some flat track and tt. So I dont need a race motor

[havinnoj]

Here are the 2 budget-friendly builds (that you can buy new today) that I would consider.  For the price, it's hard to beat the ESR builder cylinders.  $600 for a 350 cylinder with piston, head, dome, gaskets, etc.  Send it to your favorite builder to get ported.  You could even throw a +4 crank in the build.  The next option would be a CPI Sphynx but retail cost is about double that for a plated cylinder, piston, head, dome, etc.

[The_Steve_Man]

You have experience with these?

[The_Steve_Man]

I dont mind spending the money. I just dont want to get a cylinder then find out that I could have spent a little bit more and got something better. That is why I am looking for feedback what people are using.

[etccb]

Tuff to beat this package.
http://www.eddie-sanders-racing.com/product_p/330-76mm-stroker-kit-npv.htm
Plus they will mod your bare case for free where all others charge near 100 more for that.
You could call them and set the package up to suit your needs.

[Rupp250]

For the bang for your buck, deffiantly talk to Eddie, I have experiance with both the ESR cylinder and the CPI setup.

[aberegg05]

I have the 330+4 esr cylinder 9 port and pipe. I ride trails.  Does great for me on low end and rips on the top for when I want the speed on the road. Def got more than what I paid for.

[Victork]

I had a esr 310 with mid/top porting that went well. Id get the esr builder cylinder and send it to arlan for low/mid power

[Daniel370r]

Can't beat eddies prices I'm building one now on a budget, but my next one will be from led. If you had the coin I would get a ported sphynx cylinder and big bore pipe from Arlen. Then put it together myself.

[The_Steve_Man]

Thanks for all the feedback. I will be thinking about which ESR kit to get.
I still have another option on my mind but requires a little more work.

[The_Steve_Man]

What crank would I need to make it a 350 with the 350 kit?

[rsss396]

new +4 hot rod cranks are hard to beat for the price, you can find them on ebay pretty cheap. Or ESR can stroke your factory crank

ESR big bore cylinders are the price leaders, hands down the best bang for the buck. if you want a little more out of the same size motor than the CP cylinders are the best power IMO.

CP prices
http://trx250r.org/threads/1475-Sphynx-and-Puma-cylinder-Retail-price-list

[havinnoj]

What crank would I need to make it a 350 with the 350 kit?

Eddies 350 kit comes with a 78mm piston.  78mm piston with stock 72mm stroke is 344cc's.  You can use your stock crank or a +4mm hot rods with that setup.  The kit [MENTION=70]etccb[/MENTION] posted looks like a 76mm piston with a stroker crank so that's also 344cc.  You can run through the numbers in our site's engine displacement calculator here.