[gashousegorilla]

      We have already wrung out about as much as we can from 500 cc UCE on the street .... 36 HP and 38 ft lbs. at the wheel.  And that was with keeping most of what was there already  or readily available parts, or modified stock parts for the most part.    Keeping a sane rev range in mind all along...

 Welp...  lets see what this configuration can do on the street ?  540 displacement ,  super lite CP flat top piston, lightened longer alloy rod, re balanced crank.   A few cam profile options ?  A couple of head options ?       Should be fun ?   


 

[ace.cafe]

Yes, it should be fun.
 

If you want my 2 cents,  judging by the lighter parts, you want higher revs.

So, if that is the case, I would recommend a larger intake valve and a larger throttle body. Or carb.

From what we are seeing on the 535 GT, the intake breathing is limiting rpms. But, you could use later intake closing cams to extend revs some on the regular throttle body. The added displacement will definitely affect the peak hp rpm in a somewhat lower direction. Later closing cams probably won't raise it,  but it will hold on to the power into higher rpms. Bigger throttle body or carb should do the trick. Head should flow 230cfm at full lift, if possible. A perfect 36mm orifice should flow 227 cfm. A good 36mm throttle body should be able to get somewhere near to that.

Otto is trying a 36mm, but I  haven't heard any hp reports yet.

[_Paul_]

Why use a flat top piston and not a domed high compression one? higher compression usually yields more ponies, is the UCE crank strength/longevity an issue.

Paul

[gashousegorilla]

 

Yes, it should be fun.
 

If you want my 2 cents,  judging by the lighter parts, you want higher revs.

So, if that is the case, I would recommend a larger intake valve and a larger throttle body. Or carb.

From what we are seeing on the 535 GT, the intake breathing is limiting rpms. But, you could use later intake closing cams to extend revs some on the regular throttle body. The added displacement will definitely affect the peak hp rpm in a somewhat lower direction. Later closing cams probably won't raise it,  but it will hold on to the power into higher rpms. Bigger throttle body or carb should do the trick. Head should flow 230cfm at full lift, if possible. A perfect 36mm orifice should flow 227 cfm. A good 36mm throttle body should be able to get somewhere near to that.

Otto is trying a 36mm, but I  haven't heard any hp reports yet.

 Well, we shall see ?  It's process like all things   I am personally of the belief that bigger is not always better.  It can kill port velocity when it comes to the head and intake.   But there are limits. 

  Pete Strikes again here BTW.   He has a bunch of beautiful CP pistons laying about.  And asked me if they would work in a Enfield ?    I said sure they would... but the stock rod is too short .    Beeing a fan of Smokey and being trained by Harvey Crane ..    

   LONG story short, Pete has had a very busy winter CNCing
 Alloy rods of different materials , custom and highly accurate  UCE  crank press jigs , torque plates for boring the cylinders, arbors for grinding Cams and etc.. and etc.. and etc.

   He is relentless and see's these Enfields as a challenge as many of us have....

 

Why use a flat top piston and not a domed high compression one? higher compression usually yields more ponies, is the UCE crank strength/longevity an issue.

Paul

    There are different paths to more power.    But that being said, I still have ScooterBobs beautifully made, high swirl ,  smaller chambered head.   Which will boost compression.      Don't forget , that we tested a  500 flat top piston with that head, which did quite well     That flat top AVL piston and his head, lead to the development of the 500 Domed piston.   The 500 Domed piston gives the same compression ratio as the  AVL flattop/ ScooterBob head.... performs about the same, yet it is easier and less expensive, then having a head welded up and re-done.   And no, strength is not an issue with the bottom end or the domed piston on these motors. The domed piston weighs  the same as a stock piston, so as not to screw up the balance.  The bearings in my motor when I pulled it apart looked pristine.... the truing up of the stock crank by the factory ?   Not so much .   That is why people are buying anti-vib plates !      The new lighter and longer alloy rod that we are putting in , is to match the new Lighter , shorter shirt CP piston... Also to create more leverage on the crank. 

  Like the last configuration of my motor... all things are going to be tried and tested though.

  The Rod's are proprietary  American made aircraft alloy ....200 Grams lighter then stock.

  The flat top Cp piston is 58 Grams lighter then stock.

  It's gonna rev alright !

[GSS]

      Welp...  lets see what this configuration can do on the street ?  540 displacement ,  super lite CP flat top piston, lightened longer alloy rod, re balanced crank.   A few cam profile options ?  A couple of head options ?       Should be fun ?   

Wow!  Looking forward to seeing this develop 

[Adrian II]

The Rod's are proprietary  American made aircraft alloy ....200 Grams lighter then stock.

Now if the factory (Chennai AND Redditch, come to think of it) had access to some of the materials and tooling Pete has been using we might have had a few more 500 cast iron Bullets survive without throwing a rod through the crankcases!

A.

[ace.cafe]

I also believe that bigger isn't always better. But, just big enough is better.
 

If you look at Otto and Mevocgt's power curves, they both tail off at roughly 6k rpm or slightly lower. They are 535cc with 34mm intake and 1.8" valves with 215 cfm at full lift, and IVC at around 78°ABDC(~60°ABDC @.050"). So, it is hitting mach limits at those rpms with the 34mm. When it hits mach limits, it can't reach any higher velocity,  and it would be hard pressed to handle any later IVC timing for velocity ramming effects.

Just trying to help.
Granted,  this is with our head, but it is assuredly not worse than a stock head. 

[Bert Remington]

From my perspective, playing to the strength of the 500cc UCE motor, which is medium-rpm, long stroke, two-valve, fuel injection torque, would, in combination with either a 19-tooth primary sprocket or taller profile tires, provide comfortable 65-70 mph performance margins in the 3,250-to-4,250 rpm range.

In addition to your choice of free-flowing muffler, ECU add-on and ignition upgrade, I see the following modifications providing the best ROI:

1. Peter's cams and fin intake
2. GHG/SB's porting, polishing, etc of stock head and valves
3. Hitchcock's long-stroke (+13mm, +70cc) crankshaft
4. maybe air filter and air box change

#1 is mandatory.  #2 and #3 are either or both.  I don't see the ROI for #4 at the target rpm but correct me where I'm wrong.

All of these changes can be accommodated within the stock intake and exhaust flow characteristics and capacity.  #2 and #3 have the added benefits of normalizing production tolerances to design center points which will result in a smoother and more efficient engine.

I have #1 which I will install after I reach 2,000 miles.  And before I make any additional engine changes, I'm going to improve suspension (Bel Ray 10W fork oil in front, Ikon shocks in rear, and big-butt solo seat with single, softer spring) because San Diego city government isn't wasting money on street repairs.

Or would big bore be a better ROI approach to my performance objective?

[gashousegorilla]

Now if the factory (Chennai AND Redditch, come to think of it) had access to some of the materials and tooling Pete has been using we might have had a few more 500 cast iron Bullets survive without throwing a rod through the crankcases!

A.

  We'll see !        I'll tell ya though.... that crank pressed up to .000 run out with his jig.  Spun and dynamically balanced.. NICE .     The very tips of these UCE cranks however, on the timing side ,near near the tapper and the woodruff keys are out , about .003.   Not much.. but seen on multiple UCE cranks.    Anyways , he is pumping out more Cams and rods and tooling and engine parts , then I can keep up with the testing !    "Here  try  THIS cam profile on a stock bike  "  Just today....  Geez, I'm busy.


 

I also believe that bigger isn't always better. But, just big enough is better.
 

If you look at Otto and Mevocgt's power curves, they both tail off at roughly 6k rpm or slightly lower. They are 535cc with 34mm intake and 1.8" valves with 215 cfm at full lift, and IVC at around 78°ABDC(~60°ABDC @.050"). So, it is hitting mach limits at those rpms with the 34mm. When it hits mach limits, it can't reach any higher velocity,  and it would be hard pressed to handle any later IVC timing for velocity ramming effects.

Just trying to help.
Granted,  this is with our head, but it is assuredly not worse than a stock head. 

 I hear ya !    Not going for the long ball with all this just yet....

[gashousegorilla]

From my perspective, playing to the strength of the 500cc UCE motor, which is medium-rpm, long stroke, two-valve, fuel injection torque, would, in combination with either a 19-tooth primary sprocket or taller profile tires, provide comfortable 65-70 mph performance margins in the 3,250-to-4,250 rpm range.


 You will get this particular objective with cams  and a good tune alone.... with an 18 tooth sprocket.  Cruising at 80 even .    This 540 crank piston and rod assembly , with be tested with your particular cam profile as well.   Actually first ?   

In addition to your choice of free-flowing muffler, ECU add-on and ignition upgrade, I see the following modifications providing the best ROI:

1. Peter's cams and fin intake
2. GHG/SB's porting, polishing, etc of stock head and valves
3. Hitchcock's long-stroke (+13mm, +70cc) crankshaft
4. maybe air filter and air box change

#1 is mandatory.  #2 and #3 are either or both.  I don't see the ROI for #4 at the target rpm but correct me where I'm wrong.

All of these changes can be accommodated within the stock intake and exhaust flow characteristics and capacity.  #2 and #3 have the added benefits of normalizing production tolerances to design center points which will result in a smoother and more efficient engine.

I have #1 which I will install after I reach 2,000 miles.  And before I make any additional engine changes, I'm going to improve suspension (Bel Ray 10W fork oil in front, Ikon shocks in rear, and big-butt solo seat with single, softer spring) because San Diego city government isn't wasting money on street repairs.

Or would big bore be a better ROI approach to my performance objective?

     Who.... is this Hitchcock's that you guys keep mentioning ?   

[Bert Remington]

I'm not sure of the protocol on this forum so instead of providing a URL, search for "royal enfield 570cc crankshaft" and you will see an entry for Hitchcock's Motorcycles accessories.  Scroll down to "long stroke crankshafts" and there you are!

I think Hitchcock's has a business relationship with CMW that facilitates US sales but I don't know specifics so I'm being careful.

Or did I miss the irony of rolled eyes?  I often do.

[gashousegorilla]

   I'm kidding Bert .      To be honest, I don't follow much of what  Hitchcock does.     And I think what you are referring to it for the older Iron Barrels ?   I could be wrong ?  I Don't know ?   But from the beginning with these UCE  motor here in the USA,  some of us have been doing our own thing.  I bought some basic parts from them very early on once , and had a friend try their Cams.  Beyond that.. I have no opinion or first hand experience with their stuff.   I just haven't needed them.   

  And to be clear with this project.  We are not increasing stoke, we are increasing rod length.  Closer to a 2:1 rod to stoke ratio... the displacement increase is in the bore and piston size.

[Arizoni]

Yup Bert.  I found it and Hitchcock's has one for the UCE.

1050 pounds is about $1480 USD and that doesn't include postage from England.
Postage to the U.S. on something that heavy can cost another arm and a leg.

As far as referencing Hitchcock's, we do it all the time here and haven't heard any complaints from the management yet.

Here's a link to that crankshaft

http://accessories.hitchcocksmotorcycles.com/accessory-shop/21608

Although the crank adds some cc's to the engine, the longer stroke can work against increasing the top RPM's so the horsepower gain isn't as much as most people would like.

[Bert Remington]

Arizoni - thanks for the URL guidance.  WRT to top-RPM HP loss that's the tradeoff I was willing to make in favor of mid-RPM FP gain.  Perspectives vary.

I've carefully studied, although didn't fully understand, ace.cafe's performance graphs published in the Photo Gallery.  Ditto for ace.cafe's analyses throughout this forum including this specific topic.  They are cogent and measurement-supported.  I like that.  PS I am totally awestruck at the photo sequence from aluminum block to finished cylinder head.

But I depart from ace.cafe and GHG on bore-stroke ratio and associated HP, FP and $s curves.

Again I come back to: do you want to change the fundamental nature of the engine or do you want to build on its strength?

The exhaust is restrictive for air pollution and noise emission reasons (how long can the RE remain air-cooled without an exemption, eg those black rubber fin inserts).  The ECU is tuned lean for air pollution emission and fuel economy reasons.  The ignition is price-point adequate.

Recognize what we are doing here is exiting all of the above.

The question is what best fits our performance objectives within RE's design framework.

My answer is to keep the air flow moving at RE design speeds throughout the stock intake and exhaust components, albeit more air or more efficiently.

An increased stroke does that.  But so do GHG/SB's porting, polishing, etc of stock head and valves.  Which I'm liking much more than $2K for a crankshaft plus case split.

My track Mustang is a 5L tuned for torque with a suspension to match.  Is it the fastest car on the track?  Nope!  Is it the fun-ist car on the track?  Many people agree with me it is.  My perspective...

[gashousegorilla]

Arizoni - thanks for the URL guidance.  WRT to top-RPM HP loss that's the tradeoff I was willing to make in favor of mid-RPM FP gain.  Perspectives vary.

I've carefully studied, although didn't fully understand, ace.cafe's performance graphs published in the Photo Gallery.  Ditto for ace.cafe's analyses throughout this forum including this specific topic.  They are cogent and measurement-supported.  I like that.  PS I am totally awestruck at the photo sequence from aluminum block to finished cylinder head.

But I depart from ace.cafe and GHG on bore-stroke ratio and associated HP, FP and $s curves.

Again I come back to: do you want to change the fundamental nature of the engine or do you want to build on its strength?

The exhaust is restrictive for air pollution and noise emission reasons (how long can the RE remain air-cooled without an exemption, eg those black rubber fin inserts).  The ECU is tuned lean for air pollution emission and fuel economy reasons.  The ignition is price-point adequate.

Recognize what we are doing here is exiting all of the above.

The question is what best fits our performance objectives within RE's design framework.

My answer is to keep the air flow moving at RE design speeds throughout the stock intake and exhaust components, albeit more air or more efficiently.

An increased stroke does that.  But so do GHG/SB's porting, polishing, etc of stock head and valves.  Which I'm liking much more than $2K for a crankshaft plus case split.

My track Mustang is a 5L tuned for torque with a suspension to match.  Is it the fastest car on the track?  Nope!  Is it the fun-ist car on the track?  Many people agree with me it is.  My perspective...

   Your thinking Bert !  I like it.      Most guys just say I wanna go faster .  But are not sure exactly were or how they wanna go faster  or what maybe be involved ?    YOU know.    This lighter longer Rod and piston combo is for  higher performance , more torque more HP in the mid-upper RPM's... not horrible in the bottom end.  Again.. cam dependent.     High revs.. long dwell times around TDC, less side load on the cylinder and etc.    But we are going to see what is what on the dyno.. like we have always done in the past.   This is more changing the fundamental nature of this motor, where in the past we have built on it's strength's.  Building on its strengths  is always going to be less expensive  then going into the bottom end.  Before this ... I didn't need or or want to ?   Now I'm a bit bored ?   And I want to push the limits a bit more  ?    It's fun !         And I hope it is fun to watch ?   

    If you are asking  what I think is the recipe for your  particular goals ?    Shoot me a PM or an Email .

   But off the top of my head for you...

   Yes,   a clean up job on the head... ports , chamber and a multi angle valve job, for better flow.  Perhaps Beehive valve springs for better valve control across the range....  Not a must though with cams that are not as radical.  I would just do it... because they are better springs then stock and they won't break the bank.
   
Keep the 215/ 230 Cams,  for very good bottom end and mid-range.
   
 Should you want to ?  Bump your compression ratio a bit  with a flat top  AVL Piston... or more still with a domed piston.   This will give you a more efficient burn , and more cylinder pressure for added torque.

 I think you would probably like to keep the stock head pipe  ... because it is a small diameter, good for bottom end and into the mid range.     But it will run out of breath and hit a brick wall on the highway .

  Keep your stock intake... changing the filter only is going to have very little effect.

     I like a Muffler with a tapper to it... Like a Dunstall or a megaphone or a Goldstar even ?  With tuned length header.   Catch the Hot pulse and let it expand in the tapped muffler, in the rpm you are shooting for to help scavenge .   However.... anything with a baffle will kill this effect.  Soo ..Noise ?... More performance ?   It's up to you.

  The stock bikes are not tuned lean at the factory... it's what comes out of the tail pipe after the cat gets through with it.     They actually run quite rich I have found, particularly down low.