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RE: please identify this engine
Thanks a lot for identifying the Evra/Ryobi engine. It appears one must be aware of the weak conrod and eventually an rpm limiter...?! Three questions for you all: 1) suitable fuel for general sport flying..? 2) where can I get an electronic ignition kit..? 3) if it is equipped with an rpm limiter should I keep it or disable it..? ..thanks for your input...!
Posted on: 5/16/2013 3:34 PM by Author "canardlover"
in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11513563
please identify this engine
Can you help identify this engine..?..thank you..!
Posted on: 5/15/2013 1:04 PM by Author "canardlover"
in the forum "Gas Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11512454
RE: increasing compression on Saito 4S..!?
OK folks I am at the "end of the road" regarding the .82 engine. Still got 9,800/2,000 in bench test and still with rather rough running. The tick-over is nice though, had it going for some time at 1,600-1,800 but 2,000 is stable. All on 5% nitro, 5% castor, 10% ML70 oil-balance MeOH, brand new OS F plug and 13x8 prop.and large plastic spinner. Ran the .72GK at the same time under identical conditions - even the prop nut/washer was the same..[:D]...and it gave 9,400/2,100 with much less vibrations....[:)]...sweet..! That´s it for now from my "tinker shop"....the .82 now goes into the Kelly F1 Racer and the .72 into my Ultra Sport.60.....sack time..[;)]
Posted on: 5/9/2012 3:40 PM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11074932
RE: increasing compression on Saito 4S..!?
The modified .82 engine with a head space of 1.05mL giving CR=13.8 and a squish band of 0.65mm has now been run in benchtest and showed a marked improvement in power as compared to the results on the stock engine(9,500/2,700 rpm) in post #65 above. Both modified engines .72GK and .82 were run with the same 13x8 prop. and the .82 has now "overtaken" the .72GK so the performance order is now restored: .72 GK gave 9,500/2,400 - sweet running..[:D] .82 engine gave 9,800/2,200 - harsh running..[:o]..some detonation..?? Using the .72GK as reference the modifications on the .82 has gained some 400+400rpm=800rpm gain. Why the .72 has "lost" some 400rpm since post #65 is probably a combination of warmer wheather and less nitro in fuel (5%) and both engines now have velocity stacks fitted. However, I am not at all happy with the .82 due to harsh running and vibrations so I took it apart and put the piston back in the lathe and shaved off another 0.15mm from the crown.This increased head space to 1.10mL with corresponding CR=13.2. As you see from the "balance act" pics the .82 is still markedly "under-balanced", the crank counterweight can only balance out the lightened conrod but not the wristpin, piston, ring and scuff pads. Further lightening of piston and conrod done - see pic. but this skeleton .82 piston is still heavier than a stock .72 piston...[:@]...More later after new bench test..[;)]
Posted on: 5/6/2012 12:31 PM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11070514
RE: increasing compression on Saito 4S..!?
[quote]I think that the Saito valve seats were integral W/the valve guides @ one time.[/quote] I think so too but have no pics available on the early ABC Saitos. Very much like on this Enya.60 as I remember it...Cheers[;)]
Posted on: 4/29/2012 5:14 AM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11060997
RE: increasing compression on Saito 4S..!?
[quote]ORIGINAL: SrTelemaster150 Why not make the flow divertor part of the valve guide itself? [X(] [/quote] [/quote] Excellent idea SrT, should we not pass it on to Saito....!?!?...[:D]..! Honestly I have played with the idea to silver solder a brass insert to the valve guide which has a flat underside - should be doable....Cheers..[;)]
Posted on: 4/28/2012 2:44 PM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11060426
RE: increasing compression on Saito 4S..!?
[quote]In my simple trigonometric world I would prefer to have these two lines being perpendicular to each other at "half open" valve position to achieve maximum valve opening..?!?! [/quote] Oooops, sorry folks I was dead wrong with this earlier remark. Thruth is that "net valve lift" has a [b]minimum[/b] at "perpendicular" angles not a maximum as I wrote - apparently with my brain disconnected....[:(]...!! I now sat down at the drawing board and found out that "net lift" increases rather dramatically when the angle increases from "square". Now, this explains why Saito has chosen to have the inlet valve PR pointing forwards rather than the exhaust PR which points slightly backwards. I hereby humbly apologise to Saito for insinuating they had "suboptimized" the engine.....[:(]..!!..and this indicates that they also consider - as expected - that inlet valve lift is more important to engine performance. So what I should do is to [b]shorten the PR [/b]as much as the increased sideways movement will allow. And my measurements with pushing down the valves at TDC(fire) and TDC(overlap) shows that there is still plenty of clearance to the piston crown even for this engine. SrT (and others) do we agree on this "net lift" topic...?!? And then about "valve acceleration" I think we can conclude that this also should have a minimum at "square" angle..Right..!? SrT: thank you so much for forcing me/us to dig deeper in this area....[;)]
Posted on: 4/28/2012 8:30 AM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11060107
RE: increasing compression on Saito 4S..!?
[quote]You will reap a LOT of benefits by also streamlining the exhaust port bowl. You have increased flow in the intake bowl, by doing likewise on the exhaust bowl you will positively influence scavanging, thereby further increasing the intake flow.[/quote] Yes indeed you are correct but the "operation" was so demanding that I hesitate to repeat it....[:o]...took me a whole days work in the shop and very soon now my dear wife will return home and show off her "honey do - list"....[&o].. Furthermore I fear the excessive heat on the ex. side will make it much more likely that the insert might come loose. JB Weld will not do here I believe..[8|]..! Also working through the valve seat opening made me feel like a brain surgeon at times - one slip with the grinder/drill would be fatal. Next time I think I will rather try to preheat the cylinder unit, push out the bronze valve guide and work from above. SrT:, many thanks for your viewpoints which I appreciate a lot...[;)]...regarding your second post on the pushrod length/angles I must take some time to really absorb what you said before responding. Shortening the PR is very simple I think I could take it out, shorten it and have it back in again in 15-20 minutes - no sweat..[:D]..provided I am fully convinced I should shorten it. Please allow me to come back on this item...Thanks..!
Posted on: 4/27/2012 2:34 PM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11059383
RE: increasing compression on Saito 4S..!?
[quote]ORIGINAL: blw Great pics. Please keep the interesting info coming our way!!! [/quote] Thanks blw and now I have a query for all of you out there. In this .82 tuning process I have milled the crankcase 1.6mm (0.06" ) and with this follows that I must also shorten the following items: cylinder base screws cylinder skirt carb intake tube pushrod tubes ...plus some other minor adjustments and from this it would be very logical to assume that I [b]must/should also shorten the pushrods correspondingly[/b]...!?!?...RIGHT..?! Well, so far in my Saito mods I have chosen [b]NOT TO SHORTEN [/b]the pushrods and attached you see two pics trying to illustrate why. If you look at the angles between the pushrod and the line connecting the set screw contact point and the rocker arm pivot point you will notice they are NOT perpendicular to each other even in the fully open position..?!? And shortening the pushrod would make things even worse..!! In my simple trigonometric world I would prefer to have these two lines being perpendicular to each other at "half open" valve position to achieve maximum valve opening..?!?! PLEASE RESPOND to this and enlighten me if there is more to it that would explain why the Saito engines appear to be "suboptimized" in this respect - and in particular the intake valve with the pushrod pointing slightly forward....Thank you....[:D]
Posted on: 4/27/2012 2:11 AM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11058696
RE: increasing compression on Saito 4S..!?
Just did some "porting" of the .82 engine and inserted a "flow diverter" into the inlet channel which has far from optimal shape in the stock engine. Had to lock it with a steel pin and a dab of JB Weld since the press fit was lighter that I had hoped for. Also grinded a bit on the outlet port but skipped the "insert" since I believe unrestricted flow is more important to the inlet channel. The "wart" you can see in the finished inlet is the steel pin just about to protrude into the channel.
Posted on: 4/26/2012 1:38 PM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11057946
RE: increasing compression on Saito 4S..!?
Howdy, got another BIG surprise when I found out through the Saito Spare Parts list that the Saito.82 share the same wristpin with the Saito.100/100GK engines..[8|]...Hmmm...must be quite some safety margin to lighten that wristpin with my skeleton .82 piston and cheese conrod..!! don't you think..? So I performed an "underwater" drilling/grinding operation (in car antifreeze liquid) using cheap diamond drills and the regular Dremel. Well, it consumed one drill completely...[:@]...and two more are rather "well done" but I got away another 0.6g of reciprocating mass - pin now at 82%...[:D]...!! Plan to start engine assembly tomorrow....Cheers[;)]
Posted on: 4/20/2012 1:55 PM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11050194
RE: increasing compression on Saito 4S..!?
OK, here the conrod and crankshaft now ready for use. Drill dia is only 3.4mm for the conrod with two additional oil holes drilled (like the 0.15/.21 racing car guys do it). Crankshaft counterweight has been streamlined into a "leading edge scoop" with blunt/square trailing edge. SrTelemaster, how do you dragster guys usually streamline your crankshafts..??
Posted on: 4/9/2012 3:55 PM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11035034
RE: increasing compression on Saito 4S..!?
[quote]ORIGINAL: Cogburn I think you overdid it. The piston will break in the strut area next to the pin boss and collapse. [/quote] Maybe, but this .56 engine is one of my best performer. It has been in regular use since modified in 2006 with many hours under the belt and I have not done anything with it yet- except adjusted the valves occasionally.Piston weight 77% of stock weight vs. 70% for the .82 piston.
Posted on: 4/9/2012 3:41 PM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11035008
RE: increasing compression on Saito 4S..!?
OK, chunky .82 piston just had my "skeleton treatment"...we will soon see if I overdid it this time...[:o].? Had to shave off -0.6mm from the piston crown in the lathe. Weight down to 70%. Will now mill the crankcase 1.0mm for CR increase plus 0.6mm to compensate for the lower piston crown = 1.6mm total.
Posted on: 4/9/2012 5:04 AM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11034173
RE: increasing compression on Saito 4S..!?
Just dismantled the Saito.82 engine and was in for a BIG SURPRISE...!!! Just look at the .82 piston as compared to a stock .72 piston.!!!..No wonder I could feel the .82 engines vibrate through my pants with piston weight at >13g (0.46 oz)....[:(] Scratching my head how to bring down the weight of that chunk...?? Measured the thickness of piston crowns(center) and they were 1.9mm vs. only 0.9mm for the .72 piston...!!
Posted on: 4/7/2012 3:13 PM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11032178
RE: increasing compression on Saito 4S..!?
[quote]ORIGINAL: downunder Quench height is effectively the same thing as squish height although they're of different shapes simply because a 2 stroke doesn't need to accomodate valves (obviously). Because no one really knows just how much this piston inertia affects clearance in a 4 stroke I'd play it safe and have ~.015'' as a minimum. [/quote] Thanks a lot for chipping in here [b]downunder [/b]- I really appreciate your thorough knowledge in this area...! Just to let you know I measured the squish band/quench height on four of my Saitos. I used a short string of solder wire introduced into the glow plug hole and pinched the wire at TDC and measured the flat part with a caliper. Measurements as follows: Saito.82 (stock NL) CR n.a. and squish band 1.5mm(0.060" ) Saito.82 (stock HB) CR=9.1 and squish band 1.5mm(0.060" ) Saito.72 (milled 0.7mm) CR=12.8 and squish band 0.7mm(0.027" ) Saito.72 (milled 0.8mm) CR=13.4 and squish band 0.5mm(0.020" ) ...so it appears as expected that the stock "US market optimized" Saitos are made for high nitro use with no squish band effect. However, my fourth engine above is now close to "optimal CR" for low/no nitro use and may have some squish band effect....!?.. And those two milled .72 engines sure run nicely...[:D]
Posted on: 4/7/2012 2:58 PM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11026235
RE: increasing compression on Saito 4S..!?
[quote]ORIGINAL: SrTelemaster150 I think that the glow plug (or in my case spark plug electrode) interfrerance W/the piston is still a concern W/either of the combustion chambers you pictured as well as the FA 150 & the most likely the FA 180 too. [/quote] Well, if so you can grind a small recess in the piston crown to clear the plug electrode (within limits of course...[;)]).
Posted on: 4/2/2012 11:55 AM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11025269
RE: increasing compression on Saito 4S..!?
Hi again SrTelemaster and others. Yes, I think we talk about the same thing, it appears to me that "Quench Height" and "Squish Band gap" would be synonymous - the gap between the outer edge of the piston crown and the outer edge of the head deck with piston at TDC...Right..?!! and to this we will have the corresponding widths and areas if you like. Just took a photo of the Saito.72 cyl/head unit for comparison and it has a quite different shape. Rather than the "pads" in the Saito.150 it has a "recess" for the valves versus the true hemi shape of the Saito.56. It also appears from photos that the glow plug hitting the piston is unlikely with the larger engines and only an issue with the smaller .40-.56 engines.
Posted on: 4/1/2012 2:53 PM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11024014
RE: increasing compression on Saito 4S..!?
[quote]ORIGINAL: SrTelemaster150 [quote]ORIGINAL: canardlover [quote]ORIGINAL: RVM Nice work on that .72! [/quote] YES, and next in line is my .82 for a similar treatment. RVM, how are you doing with your .82..?? BTW, I can tell you all that I have measured the CR of this .72 GK and with a headspace of 0.95mL it has a calculated CR=13.4....[:D]...! Hey downunder are you still with us..??!!..close
Posted on: 4/1/2012 8:26 AM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11023589
RE: increasing compression on Saito 4S..!?
[quote]ORIGINAL: RVM Nice work on that .72! [/quote] YES, and next in line is my .82 for a similar treatment. RVM, how are you doing with your .82..?? BTW, I can tell you all that I have measured the CR of this .72 GK and with a headspace of 0.95mL it has a calculated CR=13.4....[:D]...! Hey downunder are you still with us..??!!..close enough to what you recommend is it not..?..[;)]
Posted on: 3/30/2012 3:15 AM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11020812
RE: increasing compression on Saito 4S..!?
[quote]ORIGINAL: Kostas1 [quote]ORIGINAL: [color=#000099]canardlover[/color] Hello again, another update on the Saito CR increase and some more ''swiss cheesing''..[:D] Recently bought a Saito .72 GK in good shape and as usual I could not resist to take it apart for a closer inspection. Everything was in good order except that it was equipped with the early plastic rear
Posted on: 3/26/2012 8:32 AM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11015547
RE: increasing compression on Saito 4S..!?
Hi SrTelemaster...[;)]...I am so pleased to get respons from another "tinkerer"..Please keep us posted on more progress.Thank you..! Regarding the use of E85 I have tried that also but discontinued for two reasons: SMELL and SAFETY: http://www.rcuniverse.com/forum/m_3219478/anchors_3219478/mpage_1/key_/anchor/tm.htm#3219478 ..if you chose to continue with E85 make sure you have a good amout of lubricating oil in the fuel - including some castor - since you will screw in the carb needle quite a lot as compared to methanol fuel and also your engine will run hotter. One brazilian guy commented in the link above (post #15) that going to pure ethanol would be an alternative to E85 and that would also get rid of both the smell and safety issues. Could you please give more details on your spark setup..Thanks.. Good luck and keep us posted...Cheers..[;)]
Posted on: 3/25/2012 12:54 PM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11014437
RE: increasing compression on Saito 4S..!?
[quote]ORIGINAL: SrTelemaster150 [quote]ORIGINAL: canardlover Hi again all engine tinkerers..! 2)Overall it seems that milling the crankcase does not increase power much but the engine certainly runs better on 0% nitro which was my goal from the outset. [/quote] Introduce a timed spark ignition event to allow additional tuning parametres & I think you would see more benefit. [/quote] Hi again
Posted on: 3/25/2012 12:13 PM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11014390
RE: increasing compression on Saito 4S..!?
Hello again, another update on the Saito CR increase and some more "swiss cheesing"..[:D] Recently bought a Saito .72 GK in good shape and as usual I could not resist to take it apart for a closer inspection. Everything was in good order except that it was equipped with the early plastic rear crankcase cover which is rather flimsy. So I bought a new reinforced cover and gave my usual "swiss cheese" treatment and milling of the crankcase to take off 0.8mm for an increase in CR. This time I went a bit further in my lightening of the conrod. I drilled four holes each 4.2mm dia. which is more than ever before..[X(]....!! See pic of the setup and wish me luck, testing it very soon...Thank you..!
Posted on: 3/24/2012 3:34 PM by Author "canardlover"
in the forum "Glow Engines"
http://www.rcuniverse.com/forum/fb.asp?m=11013411
RE: Old YS.60 2S-need directions
Lars, thanks a lot for your input. Well I do NOT like or use Aerosynth since I think it "stinks".My favourite brew is ML70 and castor (2+1 mix to my 4S engines) which smells like perfume in comparison. Has had several positive remarks in the club field that my engines "smell good" so I freely hand out my recipe....[:D]....should be OK for the pump diaphragm too we hope.!!??..Cheers/Harald
Posted on: 10/13/2011 5:33 AM by Author "canardlover"
in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=10762850
RE: Old YS.60 2S-need directions
Many thanks Mike - just sent you an e-mail....Regards/Harald
Posted on: 10/11/2011 1:13 AM by Author "canardlover"
in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=10759301
Old YS.60 2S-need directions
Howdy, just aquired an old YS.60 RC in mint condition. A pumped 2S with baffled piston which I ran yesterday in a stand. Really powerful and the impressive tank pressure indicates that pump is still in good order. Was able to adjust it to run pretty well using the supplied spray bar glow plug and 7% nitro but still ran a bit rich in the middle range. Anyone who can help with: 1) manual for this "antique" engine..? 2) suitable glow plug..? 3) Nitro content..? 4)...hands on experience..? Thanks in advance....Cheers/Harald
Posted on: 10/10/2011 1:01 PM by Author "canardlover"
in the forum "YS Engines Support"
http://www.rcuniverse.com/forum/fb.asp?m=10758351
RE: canard foreplane loading..??
Hi guys, thanks a lot for sharing your plans and viewpoints but now is vacation time and I leave home tomorrow morning and will be out for 2-3 weeks. So do not expect any more Load factors until I´m back. Meanwhile you can "chew" on some load factors for published designs that I have calculated as follows: Gannet, .40 pusher, low wing RCM, Sept-83 Lf=142 % Dragon, .40 pusher, shoulder wing RCM, May-79 Lf=156 % Sweepee, .40 tractor FSW, low wing MA, Aug-89 Lf=172% Basic Canard, .40 pusher, low wing, twin fin MAN, Jan-85 Lf=188 % Scat Twin.40 push pull .40-.46, low wing RCM, July-89 Lf=227 % Quite a span with you Villa on the “low end� at 110% and the Scat Twin at a whopping 227%. I have an article in RCMW Nov. 2001 stating that the Scat Twin “…needs 10 degrees nose up elevator for level flight.� Not surprising at that Load factor. Cheers for now../Harald
Posted on: 6/30/2011 1:50 PM by Author "canardlover"
in the forum "Aerodynamics"
http://www.rcuniverse.com/forum/fb.asp?m=10600229
RE: canard foreplane loading..??
Dan, here is my calculation on your Sabrebat. Rather conventional but on the light side with a foreplane loading factor of 130%. The problem with most calculations - mine and the linked calculator given by Villa - is that they do NOT take the lifting force of the fuselage into account. And most of the fuse is in front of the c.g. which means that Lf must compensate for that also. No problem with you Villa having an aluminium spar as fuselage...[:D]... That is the reason why Dan (and others) must load the foreplane more. Now sack time again...Good night./ Harald
Posted on: 6/29/2011 3:20 PM by Author "canardlover"
in the forum "Aerodynamics"
http://www.rcuniverse.com/forum/fb.asp?m=10598766
RE: canard foreplane loading..??
Villa, thanks a lot for your plans which I have missed. Made a quick calculation on the "Runard" and found that your foreplane is very lightly loaded. With the proposed c.g. at 3" ahead of the main wing L.E. you have a "static margin" of 3% MAC and a foreplane loading of 110% (see attached drawing) I hope I made it correctly it is sack time now here in Sweden. Dan: would it be possible to do the same with some of your canards..?...Good night/Harald
Posted on: 6/28/2011 3:30 PM by Author "canardlover"
in the forum "Aerodynamics"
http://www.rcuniverse.com/forum/fb.asp?m=10596964
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