Red Line 53 Review

[tucfaz]

Mine uses CP20%, No problem from take off to flight except when I switch from idle-up to normal, the mid will lean out a lot! Like smoky during flight, and no smoke couple with high pitch sound when I land..

[bigfilsing]

The shim just lowers the compression (slightly) by raising the head.

I don't think you'll see much difference using 15 or 20% nitro but with 30% could get some predetonation problems ( sometimes known as "diesel-ing")which isn't very good for the engine.

Cheers

[edmond22]

Mine uses CP20%, No problem from take off to flight except when I switch from idle-up to normal, the mid will lean out a lot! Like smoky during flight, and no smoke couple with high pitch sound when I land..

Tucfaz, what is your needle settings like?

I have being flying mine now for about 2 months and I arrived at factory default idle and 3 turns out on high. Of the late, I noted myself tuning the idle screw more than high needle. It seems to address my usual need to either richen or lean for the then flying weather conditions. Tubing used 2mm internal with hatori 523.

[bigfilsing]

What i think you need to remember is that model RC engines have the most basic of basic carbs on them. It's rare that you can set up and engine then forget it. In fact the only time i've done that was with an OS32 in a scale body ( NO 3D only modrate flying)

I think the manuals sometimes give the wrong impression too. Most say the idel screw is for idle to mid. Giving the impression that it's this screw for idle to mid mixture. Fact is that the idle is for idle and effects the mixture to "about" mid where it's effect is minimal/runs out and is over shadowed by the main jet. I always think of it as critical for the first 30% of opening with the main jet taking care of the other 70%.
It's then down to the main jet to "try" and get a linear fuel delivery to the engine according to the throttle body opening. Thats asking a lot from a basic jet ( and why we see some major needle mods done on some older engines)

Without seeing the carb it's difficult to see how the "mid" screw effects the other 2 screws. It could be just a general mixture screw effcting both idle and high end screw ( ie' the complete fuel delivery system) or specifically for the mid range.

Good luck

[tucfaz]

I'm also using the 523 but with 20% CP. my low is about 1 turn open from flush, and high is set at 2.5 turns.

Like I say. No problem with take off and flying, but the engine will lean out when I switch off idle mode to land, which shows that my mid is not tuned correctly..

I found the third needle, and mine was set at between 1/3 - 1/4 open.. and I've reset it to 1.5 turns from close to see what happen..

Tucfaz, what is your needle settings like?

I have being flying mine now for about 2 months and I arrived at factory default idle and 3 turns out on high. Of the late, I noted myself tuning the idle screw more than high needle. It seems to address my usual need to either richen or lean for the then flying weather conditions. Tubing used 2mm internal with hatori 523.

[tucfaz]

Theoretically.. good balance of the low and high will give us optimal mid.. which I believe is what the engine is suppose to be tuned for.

With the Hyper50. I'll not have any problem achieving this balance.. but with the RL53. There's this other nozzle (The third needle)

Take a look at the picture.. the longer nozzle is where the throttle arm and "third needle" is. and the shorter one is adjusted via the low end screw...

What i think you need to remember is that model RC engines have the most basic of basic carbs on them. It's rare that you can set up and engine then forget it. In fact the only time i've done that was with an OS32 in a scale body ( NO 3D only modrate flying)

I think the manuals sometimes give the wrong impression too. Most say the idel screw is for idle to mid. Giving the impression that it's this screw for idle to mid mixture. Fact is that the idle is for idle and effects the mixture to "about" mid where it's effect is minimal/runs out and is over shadowed by the main jet. I always think of it as critical for the first 30% of opening with the main jet taking care of the other 70%.
It's then down to the main jet to "try" and get a linear fuel delivery to the engine according to the throttle body opening. Thats asking a lot from a basic jet ( and why we see some major needle mods done on some older engines)

Without seeing the carb it's difficult to see how the "mid" screw effects the other 2 screws. It could be just a general mixture screw effcting both idle and high end screw ( ie' the complete fuel delivery system) or specifically for the mid range.

Good luck

[bigfilsing]

Theoretically.. good balance of the low and high will give us optimal mid.. which I believe is what the engine is suppose to be tuned for.

With the Hyper50. I'll not have any problem achieving this balance.. but with the RL53. There's this other nozzle (The third needle)

Take a look at the picture.. the longer nozzle is where the throttle arm and "third needle" is. and the shorter one is adjusted via the low end screw...

I agree! getting a good mid is crucial considering a lot of your flying will be done in that area. If you have a "little" lean high end it's OK as a trade off for a good mid range ( providing you're not doing lots of consistant full throttle 3D) It's when a lot of 3D is done that lean high will cause the probs.

I can;t really tell from the pic whats what ( aside form the obvious of course)
where's the 3rd mid screw /jet nozzle??

Cheers

[tucfaz]

The 3rd needle is on the nozzle at right hand side..

where's the 3rd mid screw /jet nozzle??

Cheers

[tucfaz]

Sorry.. Correction.. I think the one on the right is a needle??, where the one on the left is a nozzle.. the needle is the one that moves towards and away (Open / close) from the nozzle at left..

The 3rd needle is on the nozzle at right hand side..

[bigfilsing]

I'm still a bit confused by your pic ...sorry.

From the pic it's difficult to imagine how the 3rd adjustment effects the carb.

Usually the jet that travels with the carb barrel is the main and the static one is for idle.

I'll have a look at the manual when i get a moment.

CHeers

[bigfilsing]

so were talking about this carb from the RL53 right?


So the "normal" high and low speed adjustments are on one side. ( left in your photo)
and the 3rd hidden screw is behined a screw on the throttle barrel.
I'm struggling to understand how this 3rd screw would effect mid ranger only.
Are you sure it's actually adjustable ??

[tucfaz]

I'll know tomorrow if it really works..

so were talking about this carb from the RL53 right?


So the "normal" high and low speed adjustments are on one side. ( left in your photo)
and the 3rd hidden screw is behined a screw on the throttle barrel.
I'm struggling to understand how this 3rd screw would effect mid ranger only.
Are you sure it's actually adjustable ??

[bigfilsing]

Let us know how you get on.

I've given it some more thought. the spray bar / needle on the right in your pic or assembly J in the dia, follows the throttle barrel and so at mid is so far away from the fuel entry point it has minimal effect so it could be fine tuning but would effect the whole range from 0 to 100% throttle opening.

All theory of course

[tucfaz]

The needle on the right is just a needle.. while the spray bar is on the left.. Hence, when you close the throttle, the needle will move forward to the spray bar.. when you open, it moves away. Wonder what's the concept behind this design.. it's like spray painting??

Well..

Let us know how you get on.

I've given it some more thought. the spray bar / needle on the right in your pic or assembly J in the dia, follows the throttle barrel and so at mid is so far away from the fuel entry point it has minimal effect so it could be fine tuning but would effect the whole range from 0 to 100% throttle opening.

All theory of course

[bigfilsing]

Yes i can see how it works.

Normally they rely on something called vortex shedding to mix the fuel with air. This is the area of turbulence that occurs behind a round object as air passes over ( around) it.

I can see the similarity with spray painting and if this is indeed the case with the "nozzel" on the left in your pic they must have designed that wroks under low pressure ( from the exhaust via the tank) Baring in mind there's a vacuum in the throttle body which draws the fuel through the nozzel as well.

The question is really ( if the needle ( on the right) is adjustable) will it effect the mid range or the whole range. I would think that as it is adjusted in relationship with the throttle barrel and moves in and out with the throttle opening or closing it would effect the whole range not just the mid.

( This is also supported by reports that it's not really a user adjustment but a different factory setting for different markets ( humidity, temp air pressure etc)

It's not clear on the diagram or photo but does the throttle move out ( corkscrew) when you open it ??
Looking at K in the diagram it has a spring so this suggest it does but i can't see the spiral grove on the cylinder that makes it move in and out??

Cheers