R/C Tech Forums - The New Werks B5 .21 Racing Engine

Hello guys, after months of testing I'm happy to say that we are finally starting to ship our new TL21B5 engine today! The B5 is our new 5 port racing engine design. Kortz has been running final specification pre-production engines for the last couple of months for a final shake down under actual racing conditions and has put his seal of approval on it!

This is exactly the same engines that Jeremy used to take 2nd at the RC Pro Series Australia race as well as make the mains at last months ROAR Buggy Nats! Actually to be specific, Kortz used 1 single engine to run both the 5 day Pro Series Australia race, the 5 day ROAR Nats as well as 5 or 6 Hot Rod Hobbies races in between! He is still racing the same engine lol but the fact that (at his level of racing) he chose to run a single engine (without re-building) at 2 races of that level plus a bunch of club racing should say something about the build quality and longevity of the engine.

Specifications on the B5 are as follows:

Stroke = 16.50mm
Bore = 16.30mm
RPM RANGE = 3000 to 39000
Output = 2.6ps at 33000 rpm
Sleeve chrome plated five ports
Piston machined out of high-silicon content aluminum alloy
Double bushed knife edged connecting rod made with special 7075T6 aluminum alloy
Composite 2 needle carburetor with adjustable venturi (7mm stock).
CNC machined, lightened, low CG cooling head design

The performance of this engine is awesome and for those that have ran our B7-Pro before it will feel like the power band has been shifted down slightly. It still provides the same extremely smooth, linear power band but with more bottom end and slightly less top end (which the B7-Pro has an abundance of lol!). We have also significantly increased the fuel efficiency of the B5 which is now a 10 minute + engine!

Most importantly for you the consumer I think is that we have taken a very aggressive approach to the pricing on this engine. I started working on the design of this engine a little over a year ago for two reason. First I was looking at the market being inundated with low cost and unfortunately often (in my opinion) questionable quality Asian made engines. I felt that we could make something better performing and of significantly higher quality working with our existing Italian manufacturing partners. Secondly I could tell the direction that the economy was going in and frankly we all need to make our bucks go a whole lot further nowadays. From these thoughts has come the B5, the first low cost Italian racing engine that is already race proven at the Nats and RC Pro Series! :D

A-main will be getting a shipment of these in tomorrow and you can find information on their site about them here:

http://www.amainhobbies.com/product_...ine-Turbo-Plug

A couple of quick photos follows, let me know if you guys have any questions!

Regards,

Ron Hopkins
Werks Racing

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At the suggestion of one of the readers of this forum I'm going to be sticking important info/posts below so that they are easy to find. If you know of a post that you feel should be here, let me know!
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Quote:
Originally Posted by rc_cal View Post
hi rons,

i just back order mine... i will put this engine in my rc8t....some question here:

1) what is the great running temp for werks engine ?
2) what is the recomended way to break in ( i would be very happy if you let me know in detail)?
3) what other brand venturi insert compatible ?
4) i have pipe 2047,3023, jp3, jp4, which one is the best for this engine ? maybe you can recomend 1...

Hello rc_cal,

Thanks for back ordering one of the B5's! Regarding your questions:

1) Normal operating temperature would be between 210 to around 250'ish degree's. I'm quoting a 40+ degree operating window because there are again quite a range of variable that can affect this i.e. weather, plug choice, pipe, track size and most definitely fuel choice. Having said that temp is secondary! Always tune your engine to get the performance that you are looking for while making sure that you are still blowing some smoke. No smoke = you are going to have a problem. Once you get your engine set with the performance that you like, take the temp and then you can use that as a reference point down the road to quickly set your motor in the range that you lik.

2) The infamous break in question lol! We're a racing company and make engines for racers, what I have found is that talk to 4 different racers and you will get 4 different opinions on how to do it lol! You wanted a detailed answer though so let the book writing begin lol!

The way that I normal do it is to set the HS needle to flush with the end of the housing and then with the air filter off, fire it up and leave it on the box. Blip the throttle a couple of times and then let it come back down to idle. Then I start to screw in the idle stop screw until I see around a 2-2.5mm air gap (opening on the slide)

******* Update 5/27/10 I'm changing this a little as we are now all using the 2010 aluminum carb. The easiest way that I have found to set the air gap mentioned above rather than try to measure 2-2.5mm etc. is just to turn the idle stop screw in 1 1/2 complete turns in from flush. This I have found is a little less than the maximum that the slide can be opened with this screw and not bind*******

When you are doing this your idle speed will start to increase so you are basically going to have to start richening your low speed needle a couple of hours (until you get a smooth, steady idle) then do a couple of hours on the idle stop screw and back and forth until you see the 2-2.5mm+ air gap (***update from above, keep screwing in the idle stop screw 1-2 hours at a time and then richening your ls a bit to bring the idle back down, repeating this until you hit the 1.5 turns in from flush on the idle stop screw as indicated above****) that I mentioned. As this is a two stroke engine, performance is always dictated by air/fuel ratio and as we are now talking about the low speed needle (remember we set the HS needle flush with the end of the housing and there is no need to touch this again for a while) if you have too much fuel (rich setting) you will have a low idle, if you have too little fuel (lean setting) you will have a high idle). It basically is a no brainer if you are too rich or lean because your engine will tell you!

Once you get a steady idle going with the large air gap that I mentioned (large air gap means a lot of air flow, to get a steady idle means that to compensate you will have to dump a lot of fuel through the engine= guaranteed rich condition and you can not damage your engine right off the bat by being too lean) I idle it through the first tank on the box. This is done basically to pump a lot of oil through the engine to flush out any metal particles in the engine and remove the minute bit of metal particles that are always released initially during break in.

Now with the radio gear on, engine off and the slide closed look down the throat of the carb and slowly start to pull the trigger. Take note of the how much throttle you are giving at the point that the low speed needle (which is connected to the slide) comes out of the spray bar (the hollow tube) on the opposite side of the carb. We will use this as a referance for tuning later on but basically what is happening is that during the range of throttle movement that the low speed needle is embedded in the spray bar, the low speed needle will affect fuel delivery (for the purist we both know that this is a simplified explanation as the fuel first travels through the HS needle circuit before going to the LS but since we already set the HS to a rich setting and will not be touching this for a while it's pretty much a mute point). At the point that it is out of the spray bar the fuel delivery (or tune) is affected solely by the high speed needle.

Then I re-install the air filter, fire up the engine and toss it on the ground. Start slowly doing figure eights at say 3 to 4 mph until you run through the tank. Then for the next tank i fire the engine up again and back the idle screw out a couple of hours. You will immediately hear the idle speed start to reduce, to compensate for this I then lean the low speed needle a couple of hours until I again hear a smooth steady idle. Once I have this I then start doing figure eights again but now a little bit fasted until the tank is empty. Next tank fire up the engine, back idle screw out a couple of hours, lean LS needle a couple of hours, do figure eights a couple of mph faster.

Basically what I'm doing with this system is slowly reducing the amount of lubricant being pumped through the engine while at the same time slowly increasing the amount of load that is being put on the engine. This I keep on repeating until I get to approximately the point that I'm pulling the trigger far enough that I know the low speed needle is being pulled out of the spray bar (remember we checked this initially while we had the air filter off) at which point your air gap (the amount the slide is help open by the idle stop screw) will have been reduced to aprox. 1-1.5mm.

****Edit 07/19/11. Once you have reached the point that you are going faster than roughly 1/2 throttle as mentioned above you are running on the HS needle which you will start tuning below. Before you do that make one final adjustment to you idle stop screw/LS needle by setting your air gap (amount that the slide is held open by the idle stop screw) to roughly 0.5mm with the reducer out. Once you have set the gap to 0.5mm, fire the engine up blipping the throttle on the box, your LS will now be rich which you will see by a low idle speed, lean the LS a few hours, blipp throttle and allow to come back to idle. Keep adjusting the LS (leaner (in) for a faster idle, richer (out) for a slower idle until you get a smooth, steady idle. By setting the air gap to 0.5mm reducer out you have now set this to the appropriate point for final tuning and you will not touch the idle gap anymore.*****

Once we get to this point we now need to be concerned about the HS needle. What I then do is re-fuel and fire the vehicle up, putt it around for a couple of minutes to heat saturate the case and the chassis and then do a quick high speed run around the track (do not hold it maxed out for a long time on the straight, this is bad). I pull it back in, temp the engine and adjust the HS needle so that I see right around 200 degrees. Then let the engine drop back down to idle and see how the idle performance looks. If the idle is now fast (it has now increased) this means that you need to richen your low speed needle (for the amount of air flowing into the engine, there is too little fuel flowing into it = lean condition) don't touch the idle screw just the LS needle. If the idle is low this means that you now need to lean your low speed needle (for the amount of air flowing into the engine there is too much fuel flowing into it = rich condition) again don't touch the idle screw.

Then I toss the car on the track for another 6-8 tanks with the engine running around 200 degrees as explained above running close to race speed but rolling off the throttle mid way down the straight. Once I'm done with the 6-8 tanks doing this we would have run around 12 to 15 tanks total through the engine in all of the steps above. I now consider the engine pretty much broken in and I'll get close to race tune on the HS setting the engine around 220 degrees. Again check to see what happens to the idle speed and adjust your low speed needle to compensate if it is high or low. Run a further 6 or so tanks through the engine driving it as you normally would and you are good to go to full race tune which will be in the 220 to say mid 240'ish range and I would consider the engine broken in and ready to be pounded on.

A long explanation but using this system helps avoid one of the most common mistakes faced by newer tuners which is setting their low speed needle too lean because they have too little air gap (the carb is hardly open help open by the idle stop screw so to compensate they set the LS needle super lean easily causing damage to the engine).

I also like to use this system because I often end up tuning and/or breaking in a lot of different types of engine with people. Using this system i never even worry about knowing what the factory needle settings are or anything along those lines. I just set the HS and LS flush with the end of the housing, set the air gap so that the slide is open 1-1.5mm and fire the engine up. How it idles immediately tells me if the LS needle is too lean or rich so I set this, then check the temp after a high speed run, adjust the HS needle to be in the 220'ish range, check idle speed and set LS so that it is smooth and steady and the engine is ready to go. Takes about 4-5 minutes total on an engine that could be completely out of whack and I've never even seen or ran before lol!

3) Ours, Sirio and possibly some of the Orion ones I would think.

4) Again we did all of our testing with our own pipes i.e. the 2013 and 3014 (3 chamber pipe) but I would start out with the JP3 initially and then test the others. The JP 4 and I'm assuming the 3023 are 3 chamber pipes so these will probably be more restrictive slightly reducing the power band but increasing the fuel economy so depending on what organization you run under (i.e. if use of these pipes is required) and if you feel the engine is over powered for you these can also be a worth while item to test.

Hope this helps!

Regards,
Ron Hopkins
Werks Racing

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Quote:
Originally Posted by sjracing View Post
Thanks..I guess I am just confused on where all the adjustment screws are located that Ron mentions...

Hello sjracing, first off thank you for picking up one of our engines! I'm sorry that your request for info is kinda getting lost in between all of this drama lol! In any case in regards to break in please take a look at my break in instructions, this is a really simply system to use and is especially good to use if you are newer to tuning these type of engines as it is virtually impossible to run the engine too lean, which is important during break in!

Now you mentioned that your experience was in running nitro planes, so you have experience tuning engines. As you mentioned planes are a little different as they only have a HS needle and of course they are cooled by the prop so temps are not so big a factor. In any case with your carbs we have 3 basic adjustments, that is the HS needle that you are familiar with which sticks up from the top of the carb on a brass post, we have the LS needle which is the one on the end of the slide right where your servo linkage connects and we have the idle stop screw which is the screw that sits at a 45 degree angle right behind the carb venturi (if you look at the engine from the top). These are the three screws that you will be adjusting to break in your engine.

The way that you have to look at these is that the HS affects the overall fuel delivery (across the entire range of throttle movement), the LS affects the initial fuel delivery (from roughly throttle closed to about half way open) and the idle stop screw only dictates the minimum amount of air that the engine will get or basically how far you can close the throttle. At half throttle and above you would basically tune the engine the same way that you would your airplane motor. But at half throttle and below look at the LS and the HS kinda like your garden hose and the tap. The HS needle is the tap at the wall, if you turn it wide open you can move a lot of water through the hose (or in our case fuel through the carb) but if your nosle on the end of the hose (LS needle) is barely open you will only have a little bit of water going through it. So when breaking in your engine you want to have a lot of air and fuel flowing through your engine (you want the engine to be rich). The way that you do this is set your idle stop screw pretty far open (so you have a lot of air coming into the engine) and then you have your needles open really far so that you have a lot of fuel coming through the engine also.

Following my instructions each tank you lean the needles slightly, this means that you then have less fuel coming into the engine so you naturally need to reduce the amount of air also which is why you reduce the air gap using the idle stop screw. Take a look at my instructions with the engine actually in your hand and I think that it will start to make a little sense. Keep in mind that while doing this your engine will be telling you what needs to happen by what it is doing so once you start the system it really makes sense. Give it a shot and while your doing it if you have any questions please do not hesitate to ask!

Regards,

Ron