Thoughts on pilot 400 cylinders? I also have a few questions about them...

[2-stroke demon]

Met a guy on a Facebook 250r page that has a pilot 400 cylinder/motor... he's offering to put it together & trade for my full ct/pro-x 350 motor.  I have a stock stroke hot rods crank, 86 bottom end with Hinson basket & clutch upgrade done, billet exhaust flange, drag ported cylinder, Rec 90 dome, his motor will be the pilot 400 cylinder that he says has a low to mid port(is going to ask builder again), 84mm Polaris piston, stock head on a set of cases from packard, 88 bottom end with 4 mill crank,  Hinson basket, says I would need to get an inframe pipe to fit the exhaust flange because 250r pipes don't fit?
My questions are, what are the reliability & characteristics of the pilot 400 cylinder? Does there need to be any supportive mods for it? Would my current 40.5 air striker be enough, what pistons do they use, & he says the stock heads are non removable domes but there are aftermarket heads with interchangeable ones, does anyone make heads for them anymore so I could get the correct compression To run Rec 90, or would I have to run race fuel... He mentioned speed chaser heads but said he could not find one. Also who makes pipes for these,  what's the cost range? Thanks for any info guys

[Pumashine]

That is a sweet set up. I started at 83.5 mm on the cylinder. But you can keep boring until 85mm same as a Puma. There is one company on ebay that makes a run of heads every couple of years. Interchangeable domes or have your own cut. There is not much in pipes. You must have it custom built as the exhaust flange is at a complete different angle as the trx. Im running a ESR trx9r modified with a BB stinger.

I thought I saw where Bubba Ramsey was building one for a guy on FB.

[Wes350x]

I had one, had it all rebuilt with a new cylinder and ported by FTZ. It was a monster on torque but I like a more mid-top pulling bike and it was not it. I dynoed it twice on seperate dyno's and got at most like 42-44 hp if I remember. Ended up locking it up and snapping a rod cause the 2nd Dyno guy set it too lean. Anyway, if you want a ton of low stomp pulling power go for it. If not, there are plenty other cylinders that they make now that make however much power you want. Once you mod those bottom ends they can't be used for anything else. I ended up selling the motor to Puma on .net through eBay. You can contact him also on Facebook, his name is Stepane Carrier.

[2-stroke demon]

I ride trails, want to try some xc, & do a little mx riding... Would this motor suit me? Would my ct whale pipe work well if altered?
I want something that pulls like a freight train through as much of the powerband as possible, what pistons do they run? How's the reliability? I don't want a timebomb

[Wes350x]

I want something that pulls like a freight train through as much of the powerband as possible, what pistons do they run? How's the reliability? I don't want a timebomb

That's how it was. Not a big revver if that makes sense but almost like a 4 stroke power.

Mine had an oddysesy piston. Think it came to a 391. I had a 40.5 keihin but went to a Lectron 44 at the end. The Lectron made about 4-5 more horses.

https://m.youtube.com/watch?v=OiLUVbXhoUY&feature=c4-feed-u

[Pumashine]

I'm running the 40.5 kiehen. Mine is using the Polaris 400 piston. Built by Pete Shermberger at Hybrid Engineering in Oregon. Have had no issues bottom mid or top. Pulls like a freight train anywhere.


This pic shows the pipe changes angle 2" out of the exhaust flange. I believe you can get Mat Shearer to make you one.

[2-stroke demon]

Wonder if I could find a cool head for it, Arlen at led just told me they are garbage butv that it depends on how well the cases are done

[atvmxr]

your "full CT/prox 350" doesnt have enough low end?  if it was me, I wouldnt trade

[Pumashine]

Arlen at led just told me they are garbage

Yes alot of people do bad work. Practicing, not doing what is needed. From a builders standpoint it is much better to buy off the shelf products that are easily replaceable. If you make a trade do not value the pilot cylinder more than an OEM cylinder...which has no value. In other words the pilot is not worth much.

[rsss396]

IMO - I would do a 330-370 ESR cylinder probably for the same amount of money in the the long run

[ledperformance]

The modern cylinders will perform much better. A 85 mm bore Puma for example has a better exhaust port design and the transfer lay out is much more effective. I believe it would may more power at every rpm than a Polanda or Pilot cylinder.

[Pumashine]

The modern cylinders will perform much better.  I believe it would may more power at every rpm than a Polanda or Pilot cylinder.

Yes, these motor were the alternative before the Puma was available. Pete at Hybrid Engineering did an amazingly lot of port work on my cylinder. Exhaust and transfer area's were modified severely.  In his own words "I have never had a larger pile of aluminum shavings on the floor after this cylinder was finished" It can be made into a strong runner but is not worth doing so anymore. If you just take a pilot cylinder and slap it on, you would not be happy with the end result. But I cannot tell you how much more better this motor works than any pro-x 350 I have ever had.

[wretched73]

Just looking at what's in your garage Puma makes me what a Puma cylinder over a Pilot..... haha

[Shawn]

Can you guys help me I have a pilot on 250r cases but it don't have the 400 sleeve in it. It has a 89mm bore and how do they run I need to get a crank built for it is it worth putting the money in it?

[Pumashine]

I was told you could go up to 85mm on the bore with the pilot cylinder. So you are at 89 mm with no sleeve? Interesting, got a pic?