MJD

My Feedback: (1)

The insides look as nice as the outside.. I like that. Jett gets that accolade from me too!

I-L-J or whoever: what do know about performace of the RIRE .65 Speed compared to the others? I want someone to tell me a story about them before mine arrive in the mail you see, I'm getting impatient.

MJD

rmenke

My Feedback: (13)

MJD:

Be prepaired for doing a lot of education R&D on this engine. They have been around for a few years, their basic design with 8 intake ports screams " modify me" and go real fast. I bought one from one of the German speed engine guys a couple of years ago complete with prop and pipe. The thing is so highly modified to include a OS carb it is scary. Piston sleve cut down, rod lightended etc. etc. etc. If you really want to go faster, these seem to be the engine to spend your time and money with. Mine sits on the engine shelf waiting for me to get inspired and build something approporiate for its needs. These things look like something that is going to require years of R & D to get right, and the guys that know them well are way across the pond. Look at the information and pictures "I love jetts" has in his computer. Will bet he knows how to put one of these things togeather that will scoot. The reality is that I can't stay up with several of my recent "creations" now, like the Jett 60 LX powered streemlined Q-500 killer. A unfinished Rusty "Miss Ashley" hangs on the ceiling gathering dust. There is a DC Tsunami that will be #5, on the workbench about 60% done, destined to be 60 LX powered. Call it a quick turn around pattern bird that should be lots of fun if it will stay togeather. You know guys, I think that the normal people out there that call the "Brotherhood" a group of strange phobic nuts may just have something there? ENJOY Bro # 119.

I-Love-Jets

Well, the OPS .65 and its fully interchangeable “brother“ OPS .67 ( = perfect spare part supplier) are the most powerful 11 cc aero conversion engines available - already non-modified!

The 13 cc OPS .80 “VAE“ cannot reach as high top rpm as the OPS .60 VAE, the .65 “VAE“ and the .67 “VAE“. But the .80 VAE as a more torquey breed is able to operate more pitch at nearly same top rpm. The .80 does weigh only 50 grams more than the .60, the .65 and the .67.

As for the achievable rpm numbers (unloaded), these can be found in post #24 of this thread. These numbers will only be reached with the venturi speed carb mounted. The drum valve induction offers increased longevity compared to the disc rotor valve induction assembly.

Rossi #8 plugs should be used preferably, they are very durable even with 40% of nitrofuel.

The needle bearing conrod OPS versions potentially can be used with only 12 to 15% of oil. However I personally would never go below 20% of oil. High performance .90 sized speed engines such like the OS .91 VR-DF or the BVM .91R should be operated with at least 22% of oil.

The tuned pipe length starting point for the .65 or .67 is about 12“ (between glow plug and middle of the fat part of the pipe). Depending on your choice of prop, pipe make and nitro content you can reduce pipe length to about 11“. The engine at full throttle should struggle to kick into resonance at the ground. However, by pinching the fuel line the engine should get it into first-stage resonance without effort. Then the pipe length is set correctly for absolute highest achievable rpm after a terminal dive.

The pressure fitting must be placed at the beginning of the converging cone of the tuned pipe (when the diameter of the fat part starts to decrease) to gain highest and constant pipe pressure for the tank. If the tuned pipe does feature a deflector plate instead of a twin cone design, the the pressure fitting has to be placed right in front of that plate.

Only use bubbless tanks! The OPS .60 to .80 engines require a minimum of 250 ml of fuel capacity for a 2 minutes speed run at full throttle.

The needle has to be set rich because of the huge unloading potential due to the oversquared prop sized used! Just let the OPS produce a big white smoke trail. In Germany all Speed Cup freaks do mount an external R/C operated needle such like the very recommendable BVM R/C mixture control unit. Such a mixture controlling device is an absolute must in combination with the venturi speed carb to guarantee best top speed results and long engine lifetime. http://www.bvmjets.com/Pages/mixcont.htm


To conclude, the actual 7-ports OPS .67 is very well suited to potentially break the 250 mph “barrier“ with the appropriate speed plane and speed prop setup. [sm=tongue_smile.gif]

SpeedBoy

O M G !!!

This is that I would call THE MUSCLE ONE .

I-Love-Jets

So how to break-in that OPS “muscle“

Please never try turning the piston over top dead center by hand on a brand new engine just for fun! You will potentially harm the piston/sleeve fit, i.e. the chrome plating surface at the pinch point as well as the SI-aluminium of the piston => extreme lifetime reduction!

When swapping the front and rear housings for the aero-conversion check-out all engine internals carefully for possible metal swarfs and dirt contamination in general.

Use an engine test stand (home built if you want) for the break-in procedure and to fine-tune the pipe length

Shorten the diameter of your favourite (most promising) carbon fibre prop to 85% and rebalance. So an 8“ diameter becomes 6.8“ for instance. The reason for that shortening is that the trimmed-down propeller simulates full throttle engine load (in-flight) already on the ground! So this procedure is essential to determine the correct pipe length for maxumum output. This shortened prop represents a test-prop for ground testing purposes without exception! The same propeller model at 100% of diameter will be applied for the speed flights finally.

Note: The propeller blades and the prop hub must never be in contact with the spinner cap. Only the spinner back plate may keep in touch with the prop.

Never stand in front of or next to the propeller circle! Only behind the engine people are 100% safe!

Wear safety goggles during engine tuning (yes the large flexible plastic ones that can be used by spectacle wearers too)!

Wear ear protection especially if using a straight non-muffled tuned pipe.

Use the electric starter only - forget the chicken stick when dealing with carbon fibre props.

Because we want the brand new piston/sleeve assembly to achieve a long lifespan we do assist to reduce piston-pinch BEFORE the very first propeller flip. For that the brand new engine cylinder must be heated evenly by a heat gun. Focus on the finned cylinder part right below the coloured cylinder cooling head. That is the part of the engine mostly affetcted by thermal material expansion. In fact this heat gun procedure simulates the intended material expansion of aluminium, SI-aluminium, brass and chrome of an ABC or AAC assembly at correct operating temperature during full throttle - meaning the optimum piston/sleeve fitment characterised by a minimum of wear is assured right from the very first engine fire-up.

For the break-in procedure the engine always must be operated at full throttle to gain the regular operating cylinder temperature as soon as possible! So please mount the venturi carb.
[ul][*] Start the engine and let it run at full throttle for 1 minute. Stop it by shutting-off the fuel supply.
[*] Let the engine cool down for 5 minutes.
[*] Start the engine and let it run at full throttle for 1 minute. Stop it by shutting-off the fuel supply.
[*] Let the engine cool down for 5 minutes.
[/ul]
Repeat that heat cycling sequence 10 to 20 times and the engine break-in procedure is finished. Now the piston/sleeve fit is optimised for full throttle operation meaning that the piston/sleeve assembly will deliver the top end power you expect from the OPS engine (about 25000 rpm unloaded).

After the final flight of a day please use straight 80:20 FAI fuel (zero nitro, castor oil) for the ground after-run procedure. Let the engine run for about 30 seconds at full throttle and shut-off the fuel supply. The now nicely heated engine does help evaporating the residual methanol within the engine. The residual castor oil as an antirust medium will protect the engine internals effectively, in particular the ball bearings.

daven

My Feedback: (1)

Quote by RMENKE:

You know guys, I think that the normal people out there that call the "Brotherhood" a group of strange phobic nuts may just have something there? ENJOY Bro # 119.


No Roger, its just you

tlrascal

My Feedback: (56)

I agree with the break in procedure except for one important difference. You should richen the mixture to stop the engine rather than pinch off. This protects the engine and preserves the glow plug. This is also how you shut down with an adjustable needle valve, richen it.

I-Love-Jets

Well, in F3D pylon racing as well as in F3S speed flying the most common method to stop the engine still is to cut the fuel supply by a servo (constricting the fuel line by pulling a U-shaped 1.5 mm steel wire, see picture below).

Because of the superior lubricating characteristics of castor oil all potentially endangered hot engine parts (piston/sleeve + lower end of conrod) are lubed satisfactorily during running-dry.

A quality micro servo such like FUTABA S 3116 SPEED (20 N cm) will do that shut-off job.

MJD

My Feedback: (1)

If the fuel supply is cut off suddenly, as opposed to a couple of seconds of starving lean as the tank runs dry, would I still expect to kill plugs?

I thought the squeezing off of the fuel supply at the end - where the engine goes to full lean and beyond for a few seconds with the venturi/throttle valve wide open, or starts sucking bubbles on a clunk tank - is the big problem.

My West .50 V1 has maybe 20 flights on the plug in it right now, and it has run the tank empty several times at full tilt, and been killed with the throttle as well. The plug is fine, the piston/cyl fit is still squeaky tight at the top, and it idles beautifully once warmed up. What am I doing wrong? [sm=confused.gif]

MJD

RocketRob

My Feedback: (1)

Thank you ,I Love Jets!
Some very good information - I greatly appreciate your detailed posts!

vicman

My Feedback: (10)

Hey! I'm not phobic![8D]

bob27s

My Feedback: (19)

Rapid pinch-off works fine. Does not create a temperature rise like leaning it out or running the engine dry does.

Throttle barrel shut off works fine too .... like the airvalves we use on the racing engines. But those shut off air, and they also shut off the fuel (barrel blocks the spraybar when closed).

Flood off can be ok, but one has to be VERY careful. Too fast, and you will hydraulic lock the engine.

Bob

MJD

My Feedback: (1)

Thanks very much for all the detailed information! I can't wait to check out the OPS .65 when it gets here. Now I must go check the mail.

MJD

I-Love-Jets

What you need now is the right airframe, whose aerodynamics will force the engine to unload massively and that doesn’t restrict the propeller slipstream of the highly oversquared carbon fiber prop.

That kind of very low drag airframe is not too complicated to design and built - combatpigg for instance has designed a nice one in the past.

freakingfast

My Feedback: (3)

It's that black thing in front we'd like to get a hold of, the rest is useless without it.

tlrascal

My Feedback: (56)

The easiest way to kill the engine is with a pinch off and I did that for several years. Then I found a better way and that is to gently richen it until the plug quenches and believe me it doesn't have to be grossly rich. That allows you to examine the plug and determine a number of things. If you pinch it off the element takes a final beating and it is hard to analyze the plug. I used to make a remote needle valve which allowed you to do this and it was only a few grams and about 3/8 inch square. Within days of me giving these to top competitors new Formula I records were set with it.

I-Love-Jets

Some more notes being very important:

Before removing the piston/liner of a used OPS engine you have to mark the actual sleeve alignment versus the aluminium engine cylinder housing. I normally use a sharp carpet cutter to cut a small single score both into the brass and the aluminium (see pics below). Please do only cut the brass at its outside part of the liner lip to exclude future compression loss!

After removing it is now possible to position the sleeve exactly to its original location. This is very important because no engine sleeve is honed and no piston is machined round 100% (this applies to all IC engine makers).

For that all of my brand new engines, that don’t come with a pin predetermining the liner position, do receive that small but important “positioning-score“ right from the first day.

The piston itself of a used engine must always maintain the same direction in order to retain the best piston/sleeve fitment and compression. So please never 180 degree rotate the piston...

Be also sure to mount the conrod correctly. In case of the rear intake OPS engines the small lubricating bore of the lower rod end must face the rear namely the disc or drum rotor.

In an OPS .60 FIRE or FISE engine however that small conrod lubricating port has to point towards the engine front.



Finally I would like to add that while inspecting a brand new engine internally for dirt contamination it is advisable to apply a good amount of lube oil (pure castor oil)
[ul][*] to the crank pin/lower rod [*] to the piston pin/small rod end[*] to the chrome of the liner and [*] to the ball bearings [*] to the rear disk or drum rotor[*] to the crank pin driving the rear intake valve
[/ul]
before the very first engine start. Sometimes brand new engines are delivered sort of “dry“ (lubed insufficiently).

MJD

My Feedback: (1)

So.. dumb question here - if I engage the crank pin with the disk valve but to the wrong slot in the disk, i.e. the one 180 degrees away - do I get a reverse rotation RIRE engine..?

MJD

dhal22

goodness, that's the most thorough breakdown of an engine i've ever seen or read. makes me a lot more likely to operate one of these monsters. while i'm at it, i have an OPS 60 Speed SPA/RCA with OPS headers and pipe, it also came with a extra perry pump backplate and perry carb. what is it's parameters and applications?

thanks, david

I-Love-Jets

Yes it is easy to convert the OPS RIRE disc rotor versions to reverse rotation. This a nice option for marine applications, for example a twin powered rigger. [8D]
[ul][*] just rotate the rear disc rotor back plate 90 degrees counter-clockwise and [*] use the opposite rotor driver groove (see pics below)
[/ul]
So the OPS potentially can be used as a pusher power unit still applying the “regular“ counter-clockwise 2-blade speed carbon fiber props. But such high performance pusher engines usually need a heat sink cylinder cooling head to keep the temperatures low.

Because mainly of that single temperature related limitation you won’t find any pusher type IC powered purpose built speed planes in Europe for instance.

The OPS .60 to .80 drum rotor valve cannot be used for reverse rotation operation sadly. [:@]

dhal22

with the reverse rotation could i finally use that pusher prop i've had laying around for yrs?[X(]

david

I-Love-Jets

Below attached you can see the actual OPS .60 Super SPP VAE, the hottest 10 cc FAI compliant engine available. It now comes with the drum rotor rear intake valve (identical to the one used with the actual OPS .67 marine) instead of the earlier disc rotor (but the disc rotor assy still is available). You will also detect the black carb neck steel sleeve (= spacer) needed for fitting the 14 mm dia carb neck to the 16 mm bore collet.

For maximum top end output this OPS .60 VAE has to be operated with the below pictured venturi carb.

MJD

My Feedback: (1)

I still say it is about the sexiest looking engine I have ever seen.

Rest assured I have no intention of running my OPS engines in reverse, but I was curious if that could be done.

MJD

dhal22

my 60 speed has SPA/RCA on the box. what does that mean?

david

I-Love-Jets

.60 SPA RCA means it is designed for pattern flying purposes.


You should take a 11x8 sport prop and fly it with a classic 70's and 80's RCI pattern plane at 16000 to 17000 rpm.

So these goldhead .60 engines that were available as FIRE and FISE versions are timed for torque primarly.