I thought I'd write a short review of the very first Laser enginethat I've seen 'in the flesh'.The particular engine is a 70, the smallest Laser currently makes.Quality and workmanship are obviously extremely good. Perhaps the mostnotable example of this is the rocker cover; while this is a trivialexample, it does show the attention to detail and desire to make a firstrate product. It's fully machined from solid aluminum and overcuts arenearly nonexistent. The rest of the engine shows the same commitment andattention to detail.It's often mentioned how short Laser engines are compared with other4 cycles of similar displacement and this is true. The Laser 70 isactually slightly shorter from the bearer beams to the top of the rockercover than a YS.53 is. What is usually not mentioned is how narrow thecrankcase is; this is actually even more impressive although perhaps notas important as engine height is to those trying to cowl around one. Alot of displacement has been squeezed into relatively small package.All steel wearing parts are hardened and the cylinder is NicaSilplated.
Up for sale is a Laser 200 V-Twin four stroke nitro engine. This engine is sold in the United States by Proctor Enterprises. More information on Laser engines can. This is a fantastic running Laser 200 four stroke V-Twin. The engine was bought it with a Proctor N28 kit. The engine was carefully hand lapped.
The piston is nearly conventional except it has a 'ring and ahalf'; there is a second ring below the first compression ring althoughthis is listed as an oil control ring rather than a second compressionring. The cylinder and head are quite wide making for massive coolingarea. These engines are reputed to last a long time and their design andappearance would certainly seem to indicate this.Unlike most current 4 cycle model engines these engines are somewhatdifferent regarding the valve train and valve train location, and thecarb.
And muffler mounting are quite different. Rather than usingthreads to hold on the exhaust nipple and muffler, Neil Tidey uses anO-ring and clamp arrangement to secure both the carb. And muffler (thereis no header per se).
This allows quick removal / installation as wellas full 360 degree positioning of each item. The muffler mounts directlyto the head and it's quite small; even considering it's size most of itcan be tucked behind the cylinder leaving very little muffler stickingout.
There is no intake pipe for the carb. Either, it mounts directlybehind the head and points directly into the intake valve. A clever andsimple way to mount both devices. The entire valve train is mountedbehind the cylinder. There are two independent cams located behind thecrankshaft and these operate conventional push rods and rocker arms. Oneunusual aspect is that the rockers and valves are set at quite an anglecompared to conventional model engines.
This is where Lasers gain asignificant height advantage over more conventional engines; there ismore of the rocker behind the cylinder than there is above it. Further,this layout will protect the entire valve train assembly from crashdamage; to bend a push rod or push rod sleeve one would have to actuallybreak the cylinder.
After a crash that bad the push rod condition isquite meaningless.Running- The engine started readily, ran and idled well. Fuel wasK&B 500 (12 1/2% nitro, 17% synthetic oil and 1% castor oil) althoughthe owner usually uses 10% nitro with 15% all synthetic oil. Poweroutput is reasonable for a normally aspirated (non- supercharged) engineof this displacement and weight, turning an APC 12-8 to 10,500 rpmpeaked. No difficulties, oddities or problems were noted.Overall, a high quality, well made engine.
About average in weightbut short and wide for it's displacement. Noise output seemed aboutaverage although I did not measure it.OPINION: The following is my take on these engines.
Or, this is thepart that should generate the most flames:-)It would not be a mistake to buy one of these engines and I can'timagine anyone happy with any conventional, normally aspirated 4 cyclemodel engine wouldn't be quite pleased with one of these. They arebetter made than the average Japanese 4 cycle and use superior materials(hardened valve train components, cylinder lining, ring(s), etc.).The upside: These engines are short and have narrow crankcases fortheir displacement. Fitting them into a tight cowl space, which is oneof their long suits, is where they hold their best advantage.
Further,the generous finned area would make them cool better than most Japaneseengines of similar displacement. Laser engines become something of abargain when comparing their twins to Japanese twins. All Laser enginescurrently made are 'V' twins and they cover quite a range; from 1.60 to3.0 cu. While the price increases substantially, itdoes not jump into the ridiculous territory that Japanese multis seemto.The downside: there are two basic problems. 1) Lasers actually offerlittle over conventional Japanese engines other than simply being madeof better materials.
As the Japanese engines seem to last for years andyears, one has to wonder how much of an advantage this is. Put anotherway: this engine may well fix several problems that no one has. 2) Inthe US, the single cylinder engines are rather expensive compared withJapanese engines of similar displacement and power output. In the UK,Japanese engines cost so much that Lasers are actually competitive pricewise and therefore a good value; here this is not the case. A Laser 70is £200; at current exchange rates, this calculates to $300. An OS.70is readily available for less than $200 and compares will with a Laser70 overall, and for $215 a Saito.91 can be purchased which is bothlighter and more powerful.For specifications, prices and photographs, the link is:Brian'You can always tell an Engineer.But you can't tell him much.' David Larkin27.05.00 0:00.
Brian,I was hoping you would comment on Jim's engine and find your commentsinteresting.Perhaps there are some more comments that can fairly be made:The LASERs are designed for sport and scale use and consequently performreliably in cowlings, and in different mounting positions - there is noneed to add a nicad if you mount your engine inverted! The fact thatLASERs are so user friendly is not insignificant. Pleasure of ownershipand operation is important. The fact that LASERs are overwhelmingly themost successful engine for FAI R/C Scale use says something for theirreliability and dependability in this type of application.Within the single cylinder LASER range there are differences of approach.Some are designed with particular emphasis on power, others have beendesigned more with compactness in mind, than specific power.I think if you had actually made noise measurements you would have found asignificant difference between the LASER and other four strokes. I havedifficulty hearing my LASER 80 if several planes are flying.While LASERs are expensive, I see a number of repeat orders from LASERusers. Consequently I infer that their owners are happy with the valueofferred.Best regardsDave LarkinCregger27.05.00 0:00. All right, I'll let you get away with that one Brian!:)Important point though.
The Laser 70 also spins 12x8@10500rpm using 0%Nitro (but only on 15% oil, if you add more they tend to slow a fair bit -20% makes them run really badly especially those over ). Sorrycouldn't let that one pass:)Relatively the Laser is far easier to handle at least on the designed fuel(unsure about how they handle on Nitro), in that I have never had a kickback from any of my friend's Lasers (damn - must get one). These include a70, 80, 150 and a 100 and soon a 200V-Twin.Laser also can be made to idle incredibly low. I think I got the 150 downto a flight idle of 1500rpm on straight fuel. For some reason my pal wasn'thappy flying with a 1300rpm idle:)RegardsChrisBrian D.
Felice wrote in messagenews:[email protected] Archer28.05.00 0:00. Does not usually seem to be a problem Ed, Laser seem to 'suck' fuel moreefficiently than most four strokes. The only time I've ever had theslightest problem was with an old (1964) Laser 61 mounted upright in an oldLou Andrews Aeromaster.
The guy who built this mounted the tank very low,leaving a distance of aver an inch between the TOP of the tank and thespraybar. This model does tend to load up a bit during prolonged invertedflight.Most Lasers that I have seen are mounted inverted.-Best regardsJim (night owl) Archer, Norwich, UKCregger wrote in messagenews:[email protected]. Since I abide by the rule that says that the level of the fuel tank centerline must be within 3/8' of the carburetor's spraybar, how wouldthis affect fuel tank installation in 'normal' model airplanes? Especially with inverted engines.
Ed Cregger Brian D. Felice wrote I thought I'd write a short review of the very first Laser engine that I've seen 'in the flesh'. (snip)Brian D. Felice28.05.00 0:00.
Hi Chris,Yes, I know the Laser is cut to use zero nitro fuel and have no doubt thatit does this with ease. I did forget to mention this but also feel that it'svirtually insignificant in the states (US) anyway as we usually use either 10%or 15% fuel anyway. I've never even seen no-nitro fuel for sale here locallyalthough it is available mail order. Bear in mind that I wrote that from thepoint of view of the American modeler and no-nitro fuel isn't a significant goalhere.I saw Jim start the Laser one time by hand and it certainly started readilyon the 'backflip' but then again, so do most Japanese engines. There did notseem to be a significant difference in it's behavior when compared to other 4cycles of it's displacement.The only engines that have truly impressed me with low idle have been OS.70's and.91's.
They will continue to idle at speeds that should have shut themdown handily. The Laser had a fine low end that was absolutely reliable and morethan acceptably low but not in the best OS class.I only saw this engine in action a handful of times and do not own one; Iwould certainly not consider myself a Laser guru. It may well have subtleattributes that escaped me.
Also, I tend to compare all 4 cycles with regard toOS engines because they are so common here and they are extremely conventional-it's easiest for me to think of other engines as to how they deviate from OSs.Rgds,Brian'You can always tell an Engineer.But you can't tell him much.' Chris Hinds wrote: All right, I'll let you get away with that one Brian!:) Important point though.
The Laser 70 also spins 12x8@10500rpm using 0% Nitro (but only on 15% oil, if you add more they tend to slow a fair bit - 20% makes them run really badly especially those over ). Sorry couldn't let that one pass:) Relatively the Laser is far easier to handle at least on the designed fuel (unsure about how they handle on Nitro), in that I have never had a kick back from any of my friend's Lasers (damn - must get one). These include a 70, 80, 150 and a 100 and soon a 200V-Twin. Laser also can be made to idle incredibly low. I think I got the 150 down to a flight idle of 1500rpm on straight fuel. For some reason my pal wasn't happy flying with a 1300rpm idle:) Regards ChrisBrian D. Felice28.05.00 0:00.
Dave,Yes, it's clear that Lasers have a good and loyal owner base. Clearlydifferent than, for example, MDS:-) Lasers have been around long enough toknow that this loyalty is not the result of three good engines. If I were tobuy one, I would also fully expect that any major flaws that occurred duringmanufacturing had been sorted out at the factory. Mass production will alwaysyield a few badly flawed examples no matter how good QC (QA to the youngerpeople) is. Neil gets around this by simply running each and every engine thathe makes and that alone would be worth something to the person starting abrand new 'brand X' engine only to find that it had a broken ring.You may be entirely correct about the noise output. I did not measure itnor were there any other 4 cycles around to compare it with other than my YS.It was significantly quieter than the YS but this is to be expected due toturning slower, using less nitro and being a smaller engine.
Certainly it wasnot any louder than, say, an OS.70 although the exhaust system is bothsmaller and lighter. I know the recommended BMFA noise levels are very low andthese engines seem to have no difficulty meeting them.Brian'You can always tell an Engineer.But you can't tell him much.' David Larkin wrote: Brian, I was hoping you would comment on Jim's engine and find your comments interesting. Perhaps there are some more comments that can fairly be made: The LASERs are designed for sport and scale use and consequently perform reliably in cowlings, and in different mounting positions - there is no need to add a nicad if you mount your engine inverted!
The fact that LASERs are so user friendly is not insignificant. Pleasure of ownership and operation is important. The fact that LASERs are overwhelmingly the most successful engine for FAI R/C Scale use says something for their reliability and dependability in this type of application. Within the single cylinder LASER range there are differences of approach. Some are designed with particular emphasis on power, others have been designed more with compactness in mind, than specific power. I think if you had actually made noise measurements you would have found a significant difference between the LASER and other four strokes.
I have difficulty hearing my LASER 80 if several planes are flying. While LASERs are expensive, I see a number of repeat orders from LASER users. Consequently I infer that their owners are happy with the value offerred.
Best regards Dave LarkinBrian D. Felice28.05.00 0:00. Ed,The example I saw (Jim's 70 in a AcroWot) was side mounted and presented noproblem. I don't know if you could center the spray bar to the C/L of the tankshould the engine be mounted upright or inverted. I also don't know how much ofa problem it would be to offset the spray bar to C/L by, say, 1/2 to 5/8 of aninch though; it may not be a significant problem.
These engines typically don'tuse muffler pressure so I assume they have a reasonably sized venturi in thecarb. In the first place. Any tank placement problems are aggravated by the nowcommon practice to use a very large carb. Throat for a given engine size.Brian'You can always tell an Engineer.But you can't tell him much.' Cregger wrote: Since I abide by the rule that says that the level of the fuel tank centerline must be within 3/8' of the carburetor's spraybar, how would this affect fuel tank installation in 'normal' model airplanes? Especially with inverted engines.
Ed CreggerDavid Larkin28.05.00 0:00. I think that quality control at AGC is more than just testing. Apparently GeorgeAldrich visited the factory and was shown around. He was impressed. Afterwardshe was chatting with Neil and said that while he reallly liked the engines hewasn't in the market for one just then - but could he have a reject part as asouvenir?
This caused a pained expression to pas over Neil's face 'Actually,George, we don't make any reject parts.' However he gave George a valve cover totake home.Also Neil keeps very close tabs on the behaviour of his product. It's a habit ofhis, I'm told, to ask club members if they would mind if he unbolted theirengine and took it back for stripping and examination.
This way he can see howeverything is standing up under field conditions. Improvements are fed in tothe production progressively as they are developed, like the switch to ABN andthe switch from Supertigre to Irvine carbs.
So if you are buying engines for atwin it is best to buy a pair to the same spec. I bought two LASER 50s somemonths apart and ended up with one standard and one ABN engine, though Neil saysthey have close enough the same power output.'
Felice' wrote: Dave, Yes, it's clear that Lasers have a good and loyal owner base. Clearly different than, for example, MDS:-) Lasers have been around long enough to know that this loyalty is not the result of three good engines. If I were to buy one, I would also fully expect that any major flaws that occurred during manufacturing had been sorted out at the factory. Mass production will always yield a few badly flawed examples no matter how good QC (QA to the younger people) is.
Neil gets around this by simply running each and every engine that he makes and that alone would be worth something to the person starting a brand new 'brand X' engine only to find that it had a broken ring. You may be entirely correct about the noise output. I did not measure it nor were there any other 4 cycles around to compare it with other than my YS. It was significantly quieter than the YS but this is to be expected due to turning slower, using less nitro and being a smaller engine. Certainly it was not any louder than, say, an OS.70 although the exhaust system is both smaller and lighter.
I know the recommended BMFA noise levels are very low and these engines seem to have no difficulty meeting them. Brian 'You can always tell an Engineer. But you can't tell him much.' David Larkin wrote: BrianI was hoping you would comment on Jim's engine and find your comments interesting.
Perhaps there are some more comments that can fairly be made: The LASERs are designed for sport and scale use and consequently perform reliably in cowlings, and in different mounting positions - there is no need to add a nicad if you mount your engine inverted! The fact that LASERs are so user friendly is not insignificant. Pleasure of ownership and operation is important. The fact that LASERs are overwhelmingly the most successful engine for FAI R/C Scale use says something for their reliability and dependability in this type of application. Within the single cylinder LASER range there are differences of approach. Some are designed with particular emphasis on power, others have been designed more with compactness in mind, than specific power. I think if you had actually made noise measurements you would have found a significant difference between the LASER and other four strokes.
I have difficulty hearing my LASER 80 if several planes are flying. While LASERs are expensive, I see a number of repeat orders from LASER users. Consequently I infer that their owners are happy with the value offerred. Best regards Dave LarkinLyman Slack28.05.00 0:00. Hi Brian -Great review and I have to say I concur 100% - I'm running one inmy 'Custom Live Wire' (Built for a recent Vintage R/C event from 1958plans). Great engine as far as I'm concerned; I also have a 1.20 waiting tofit into the very small cowl of the TF Bonanza currently on my bench.Take a peak at the model in the 'Hanger' section of my siteOne great point: The manuals for all the Laser line are shown ontheir Web Site.Cheers - Lyman Slack/AMA6430 IMAA1564/Flying Gators R/C/Gainesville FL/Brian D.
Felice wrote in messagenews:[email protected] Larkin28.05.00 0:00. As Jim says, this usually isn't a problem, however it is a consideration whichI feel should always be brought to a prospective owner's attention. The LASERinstructions suggest that you place the tank in the usual location relative tothe spraybar in an aircraft intended primarily for aerobatics, but that adeparture from optimum location is acceptable. Bear in mind that the LASERhas very good fuel economy so the tank size required is quite small, and thattwo seperate tanks are used for the twins.
Usually optimum tank locationisn't a problem for inverted or side-mounted engines unless you have committedyourself to a forward servo mounting location or something like that. Itwould be more of a problem with an upright engine, but upright engines are arelative rarity in fully aerobatic designs.LASERs have good fuel draw, do not use muffler pressure but benefit from alittle extra pressure provided by facing the vent line into the propwash.,Cregger wrote: Since I abide by the rule that says that the level of the fuel tank centerline must be within 3/8' of the carburetor's spraybar, how would this affect fuel tank installation in 'normal' model airplanes? Especially with inverted engines. Ed Cregger Brian D. Felice wrote I thought I'd write a short review of the very first Laser engine that I've seen 'in the flesh'.
(snip)WFTEX29.05.00 0:00. Nah, it is one of the methods used by those who have 4 strokes that have nomuffler to put a tap on.Jim Branaum AMA 1428'Another modeler supplying glue to the AMA'WFTEX' wrote in messagenews:[email protected]. Vent line into the prop wash??
That is a new one. Ken LASERs have good fuel draw, do not use muffler pressure but benefit froma little extra pressure provided by facing the vent line into thepropwash., Richard Crapp29.05.00 0:00.