[Jared_Lee]

Yeah, I wouldn't do the cam on its own. I think it's pretty easy to source enough info to make an informed decision these days. Thanks to many on this forum in fact. The performance that Tec is boasting without the cam is what I find exciting.

I don't want to completely change the bike straight away. I've had my Orange Crush for about 600 miles and I'm still getting to know it. After 1,500 miles or so I'd love to get that boost to 53 BHP on a full system 2-into-1 from Tec. That's a great novice garage project and an excellent performance improvement. Not sure where they'd land on price, but Tec seems reasonably priced for the market.

As for talk of how much money you end up sinking into the bike vs. what else you could have gotten for that money, meh. I don't want a Triumph. I don't want the badge. I don't want the color options. I don't want the look. I love how the Interceptor looks. I love how it performs stock and I'm curious to see what more there is in that little engine regardless of the cost maybe pushing me up to msrp on a Street Twin. I'd much rather own the Interceptor.

After some time on the full system configuration, I could begin to entertain the cam and compression kits. 865 big bore just seems excessive on the Int. At least to me now, sitting here with just the DNA air filter and no performance enhancements to speak of. We'll see what the future holds.

[Starpeve]

I understand your opinion, but the facts are against you, as heavy duty mick has shown by sharing his mods and dyno run. His mods gave around 3hp. Mods are an air filter, exhaust pipes, silencers, and a remap.


This engine has a 9.5 compression ratio, which is its main protection against crappy fuel. It also allows lower load on all moving parts of the engine, which can then be made lighter and for cheaper. To put things in perspective, a modern NA engine has 12:1 compression ratio and can still run on the crappy fuel you can get in India, thanks to direct fuel injection. My built turbo engine has 10.5 compression ratio, and it takes over 30psi of boost (it requires 100+ octane fuel, true. When stock, it had 7psi and 8.5 compression ratio, quite a change).

Yes, when designing an engine, you can get a pretty accurate power figure, before building it. This is 2020, not 1960, CAD is a thing. Once you get a working prototype built, if you are off too much, you just need to change the cam profiles or timing to get the power you want. Or change ignition timing to add/remove 1 to 3%. Anything higher has a chance to fail emission tests. When only fuel and timing are involved ECU tuning is very simple and cannot do much without it showing. the only way to lower engine output over this is to pull a lot of timing or remove a lot of fuel, both making the engine perform poorly, heating a lot, and failing emissions. I know this is something you will not accept, but it is how it works.

But the simplest thing to do when you get more power than you should to get the bike registered as 47HP is... to chalk it to the 10 to 12% error margin a running dyno usually has, which is accounted for by regulations. The bike does 50 instead of 47 ? Well, it still is in the error margin, so it passes.

The car industry is a bit different, as manufacturers produce way more  different vehicles. They will use (to some extent) the same engine with different levels of power. But these all have things in common: ECU controlled forced induction, and/or variable cam lift and timing. Using THESE, you can change power a lot.

That 650 engine does not have forced induction, variable lift or cam timing, nor variable admission pipe length. It is a very simple SOHC engine. So the power change that can be done with the ECU is very limited. Limiting power this way would show, there would be an obvious plateau on the power line and a sharp unnatural torque decrease.

This engine has been built for that 47hp target in mind. Is it spot on ? Probably not. Has it been tuned to deflate power ? Probably. Considering how aftermarket camshafts have a massive increase in opening time and lift, i say it was done with cams. And since someone already shown a 3HP increase with mods and a remap, i can fairly say the mandatory 47Hp figure has not been achieved by detuning the ECU.

The LS V8 I’ve referred to before has NONE of the above and yet achieves large performance gains merely by remapping. And I’m talking gains in excess of 10-15% or more.
Steve

[Starpeve]

It is a standard car ECU, there seem to be tools to remap it already on said cars.

Do not expect noticeable power gains with a remap on a stock bike, or a bike with a filter and silencer. As said above, the only way to make more power without modifying the head / cams / valves / pistons and bore is to remove the manufacturer protection against crappy fuel, which is essentially pulling timing. The head and cams control how much air enters and exit the engine. air filter and silencers can be a restriction to that, but not that much.

Anyway, if you make sure to use high octane fuel, you can add timing advance back. On car engine with 2 to 3 times the displacement, this is usually worth 2 to 5hp. So expect maybe 1 or 2 on our engines.

The problem is, you risk making holes in the pistons if you refuel with a low quality fuel batch.

Another point- it doesn't matter where or what the ecu comes from. You're not cracking the unit, you're cracking the coding, the protections around the programming. And I'm curious about the piggyback ecu's.
Perhaps they're not as effective as a modified original ecu, maybe a compromise?Or a conflict? I don't know this, just a thought.
Steve

[greentrumpet]

If you make a change to a big bore kit, and/or increase compression ratio by a specific and safe amount, you can recover any of the low/mid torque loss. See my Reply #144 above.

The problem with many parts providers is that they expect their customers to be engine builders that know this kind of stuff, and they don't provide necessary guidance to amateur builders to keep them from stepping in the shit.

Thanks, reading your post 144 again it is very clear and helpful. I was a bit surprised that a cam would be made that entails such a compromise, though I guess it helps them sell the other bits! The bike is great as standard, perhaps "just" a big bore kit would give me "that Commando grunt" that I'd like.

[Starpeve]

The LS V8 I’ve referred to before has NONE of the above and yet achieves large performance gains merely by remapping. And I’m talking gains in excess of 10-15% or more.
Steve

Footnote-
I was interested to learn tonight whilst cruising the manual that when the 650’s cpu gets a 5500 rev reading from the crank angle sensor  in a wide open throttle position it restricts fuel to the engine. Right where the torque is stated to drop off.
Described as an engine protection measure, and yet the rev limiter is set at 7250 or near.

[cyril31]

I concur that the 650 is most likely setting the power level with cam profile. The dyno charts pretty much reveal a short duration cam.

It will be interesting to see what results with the S&S cam set that other members like Gremlinsteve are trying out with their big bore kits.

This is what i think too.

I do not know the characteristics of the OEM cams, but you can easily see the difference in cam profile in the pic:
http://www.ss119.id/shop/high-compression-111-piston-kit-royal-enfield-650-twins/

The shape show a much faster and longer valve opening. I am a bit surprised by the duration though, 216/222 still feels a bit short for a race cam on a bike... but since the stock cam allows for 50ish HP, even a "short-ish" cam should net quite the improvement without sacrificing too much low/middle range. I would not be suprised to see 60HP from that cam and a remap alone.

[Bagonne]

Not to get off track but back to the original question........

how does a K&N compare to a DNA filter?  a K&N here is the US is less than a stock filter.  They've been the performance standard here for years. plenty of BS is standard here.  That alone doesn't mean anything but they are readily available and cheap

[olhogrider]

I have used both methods that the TEC video mentions, compressed air and the rope trick. Since I no longer have a garage or a compressor it was a good reminder. Remove the spark plug, put the engine at bottom dead center, fill the cylinder with nylon rope (paracord should work great!), then turn the crank until the rope is compressed against the valve face. Not sure what tool they used to compress the spring. I'll have to look again.

[ace.cafe]

This is what i think too.

I do not know the characteristics of the OEM cams, but you can easily see the difference in cam profile in the pic:
http://www.ss119.id/shop/high-compression-111-piston-kit-royal-enfield-650-twins/

The shape show a much faster and longer valve opening. I am a bit surprised by the duration though, 216/222 still feels a bit short for a race cam on a bike... but since the stock cam allows for 50ish HP, even a "short-ish" cam should net quite the improvement without sacrificing too much low/middle range. I would not be suprised to see 60HP from that cam and a remap alone.

The fly in the ointment of all this performance topic is that nobody has any hard engine data. We would like to know what we have to work with.

When I was doing the RE singles over the past 12 years, I always posted up the head flow charts over the entire lift range with direct apples/apples comparison of stock vs ported using the same flow bench for accuracy. I always posted all the cam data for the cams we made. I always gave the critical info on the pistons and their bore clearance data, etc.

Nowadays, all I see is somebody throws parts out there with little or no info,  maybe even from different makers who don't know what the other makers designed for, da da da da da da....

We always built matched systems that were made to give specific results together, and were tested and dynoed before anything hit market, and we gave unlimited tech support to customers free of charge.

I would love to see a stock head flow bench test at 28"H2O, and some real cam data and piston data.

My mentor and friend was Joe Mondello up until he passed away. I still have a lot of contacts in the biz. I can get pistons and cams made, and headwork done, etc. I have plenty of engine design experience, and even have designed complete billet heads for RE singles.
I'm semi-retired now, but I'm not dead.

[NVDucati]

Not to get off track but back to the original question........

how does a K&N compare to a DNA filter?  a K&N here is the US is less than a stock filter.  They've been the performance standard here for years. plenty of BS is standard here.  That alone doesn't mean anything but they are readily available and cheap

You might never get a definitive answer. Not many (if any) civilians will be able to, or willing to test them back to back.
I just got an email that K&N has them back in stock. In the mean time I bought a S&S. I would have no hesitation to buy a K&N. 

[cyril31]

Not to get off track but back to the original question........

how does a K&N compare to a DNA filter?  a K&N here is the US is less than a stock filter.  They've been the performance standard here for years. plenty of BS is standard here.  That alone doesn't mean anything but they are readily available and cheap

I do not have hard data about it, but K&N is known to make quality products, so the filter is probably not going to disintegrate and end up in your cylinder. It boils down to the media they use for filtration, which is usually oiled cotton, the same as DNA. IMHO it will work the same.

The fly in the ointment of all this performance topic is that nobody has any hard engine data. We would like to know what we have to work with.

When I was doing the RE singles over the past 12 years, I always posted up the head flow charts over the entire lift range with direct apples/apples comparison of stock vs ported using the same flow bench for accuracy. I always posted all the cam data for the cams we made. I always gave the critical info on the pistons and their bore clearance data, etc.

Nowadays, all I see is somebody throws parts out there with little or no info,  maybe even from different makers who don't know what the other makers designed for, da da da da da da....

We always built matched systems that were made to give specific results together, and were tested and dynoed before anything hit market, and we gave unlimited tech support to customers free of charge.

I would love to see a stock head flow bench test at 28"H2O, and some real cam data and piston data.

My mentor and friend was Joe Mondello up until he passed away. I still have a lot of contacts in the biz. I can get pistons and cams made, and headwork done, etc. I have plenty of engine design experience, and even have designed complete billet heads for RE singles.
I'm semi-retired now, but I'm not dead.

The reason we do not see this data is there are plenty of copycats. You know shops cannot bill the time  spent engineering a head to a customer, they need to split the cost between many people. Nowadays anyone can have access to 5 axis CNC mill, and there are quite some people that will just steal your work. This is why that data does not appear anymore. I am a software engineer, i do not even work in the field of mechanical engineering or engines;  this has been my hobby for 25 years. And yet as a hobbyist I can get my hands on that (and on some 3d scanner. we scanned a hand made, well prepped head, had it slightly modified to get equal chamber volume and port section, then sent a stock head on the bench to get it milled. It worked, not massively better, but better nonetheless).

You know there are 2 ways to go about it. One that does not lead to great results, consisting in throwing parts and hoping it works. It is the one that makes aftermarket parts maker and small shop live. On the other hand, it is what allows them to build highly tuned engines... Building an engine costs a lot of money, which not everyone can or is willing to pay for. So people pay for some performance dream with a silencer or air filter, and the promise it will make more power.

The other way is to spend the time and money to really build the engine. It took me and a very competent friend nearly 2 years of research, work, trial and error to build my car race engine. We wasted 2 heads in the process and an engine block. But it is done. to my knowledge, there are less than 10 of these engines that have been pushed reliably that far or beyond, worldwide. Emphasis on reliably. For 3 of them, my friend had a hand in them.

I believe there are 2 or 3 people here who are taking their modifications seriously and have results. I cannot say who from the top of my head, but i expect great things from the one who is doing headwork and a rebore.  Heavy duty mick also did a good job in my book, as far as simple mods were done, and he published his real results. Kudos to him too.

[Jared_Lee]

I don't know if this warrants a new topic or not, but it's built specifically to pair with the DNA air filter, so it makes some sense here and it's already been raised here. You'll see data attached. Tec made a 2-into-1 full system production model, not just the prototype on their shop bike. They published their dyno data on it and it looks great. When available in the US, I plan to buy it and try it.

I've read some skepticism about dyno charts supplied by parts manufacturers. I am interested to hear feedback on this chart. I am not an expert by any stretch and Ace and cyril have offered a lot of great information that I've been absorbing so far. Anyone else feel free to chime in too. I'd love to hear more before it arrives stateside!

[Arschloch]

I do not have hard data about it, but K&N is known to make quality products, so the filter is probably not going to disintegrate and end up in your cylinder. It boils down to the media they use for filtration, which is usually oiled cotton, the same as DNA. IMHO it will work the same.


The reason we do not see this data is there are plenty of copycats. You know shops cannot bill the time  spent engineering a head to a customer, they need to split the cost between many people. Nowadays anyone can have access to 5 axis CNC mill, and there are quite some people that will just steal your work. This is why that data does not appear anymore. I am a software engineer, i do not even work in the field of mechanical engineering or engines;  this has been my hobby for 25 years. And yet as a hobbyist I can get my hands on that (and on some 3d scanner. we scanned a hand made, well prepped head, had it slightly modified to get equal chamber volume and port section, then sent a stock head on the bench to get it milled. It worked, not massively better, but better nonetheless).

You know there are 2 ways to go about it. One that does not lead to great results, consisting in throwing parts and hoping it works. It is the one that makes aftermarket parts maker and small shop live. On the other hand, it is what allows them to build highly tuned engines... Building an engine costs a lot of money, which not everyone can or is willing to pay for. So people pay for some performance dream with a silencer or air filter, and the promise it will make more power.

The other way is to spend the time and money to really build the engine. It took me and a very competent friend nearly 2 years of research, work, trial and error to build my car race engine. We wasted 2 heads in the process and an engine block. But it is done. to my knowledge, there are less than 10 of these engines that have been pushed reliably that far or beyond, worldwide. Emphasis on reliably. For 3 of them, my friend had a hand in them.

I believe there are 2 or 3 people here who are taking their modifications seriously and have results. I cannot say who from the top of my head, but i expect great things from the one who is doing headwork and a rebore.  Heavy duty mick also did a good job in my book, as far as simple mods were done, and he published his real results. Kudos to him too.

And that's a great thing that everyone has access to CNC, 3d printing, scan and measuring shops. If you want to have results you have to be in control of your design and wont have the time to control a machine shop with all it's equipment. The copy cats and smart arses are sitting there anyway, which is why you may want to spread your work so that they won't get the whole picture. Same applies for the money money factory RE.

[ace.cafe]

I didn't worry about copycats. I put my stuff out there, so people would know where it originated.

Besides, there were few enough RE single performance enthusiasts with money, so big cats wouldn't see enough profit in it to bother.

My Ace billet head for the GT535.
High flow, high ports
Big valves
Beehive valve springs
20°valve angles(vs 26.5° stock)
Totally re-designed combustion chamber(50cc)
Twin spark plug
Custom high-ratio roller rocker arms
Re-designed oiling pathways to provide pushrod oiling AND the standard squirters for auxiliary oiling.

Along with our cam design gives 38 rear wheep hp @ 6500 rpm(vs 19 rwhp stock)

We use that airbox/stack/filter design with it, that I showed pix of earlier in the thread.

I have some more radical new design inverted-flank roller cams ready to test in it, to see how they do.

[Starpeve]

I didn't worry about copycats. I put my stuff out there, so people would know where it originated.

Besides, there were few enough RE single performance enthusiasts with money, so big cats wouldn't see enough profit in it to bother.

My Ace billet head for the GT535.
High flow, high ports
Big valves
Beehive valve springs
20°valve angles(vs 26.5° stock)
Totally re-designed combustion chamber(50cc)
Twin spark plug
Custom high-ratio roller rocker arms
Re-designed oiling pathways to provide pushrod oiling AND the standard squirters for auxiliary oiling.

Along with our cam design gives 38 rear wheep hp @ 6500 rpm(vs 19 rwhp stock)

We use that airbox/stack/filter design with it, that I showed pix of earlier in the thread.

I have some more radical new design inverted-flank roller cams ready to test in it, to see how they do.

If you don’t mind me asking, what’s the $ figure for one of those lovely heads? And is there any ancillary work on the rest of the motor? Also, are you planning on anything similar for the twin?
Steve