jeffie8696

Tower no longer stocks the 65, or even the 40 for that matter. I can understand the 40 getting dropped, it had a reputation for being about as powerful as a good .25BB. But the 65 has me wondering, mine is mounted on my Great Planes Escapade 60 and pulls it around really well. Are they available elsewhere? Did OS drop them or just Tower?

Hobbsy

My Feedback: (102)

I did a search for LA .65 parts at Tower and on the .65 specific parts, like cylinder, head. crankcase etc, it says, in stock limited availablity On common parts like throttle arms etc. it say in stock. I'd say that's bad news for us LA fans. I have a blue .65 and a blue .46. Great engines.

1QwkSport2.5r

There's always the better made Thunder Tigers. They're always overlooked it seems. ....

jeffie8696

I would like to know the weight difference between the Thunder Tiger GP61 and the OS 65 LA. The OS seems much lighter to me. As you may know I am a huge Thunder Tiger fan also. But there is something about the 65LA, it just seems to work really good.

dennis

My Feedback: (90)

I would imagine that sales volume determines weather an engine lives or dies. Many who fly control line use the LA46 and it would hit them particularly hard if that engine disappears. I still have a nib FP 60 and a NIB LA65. Just don't have a use for them at present.

1QwkSport2.5r

Jeffie: the weights listed are likely with muffler (TT) and without muffler (OS). That is likely why the OS is so much lighter. (18.9oz/OS to 24.4oz/TT). 5oz for a stock OEM muffler isn't unheard of.

jeffie8696

I guess I wonder how we as engine users let this one go? It works so well I cant figure why it isn't more popular.

Hobbsy

My Feedback: (102)

Here is the LA .65 weight with muffler wearing a Davis Diesel conversion head. I can't locate the stock head. You can probably knock off one oz.
Here are some specs from the OSengines.com site

• Specifications
• Parts Listing
• Accessories

Stock Number: OSMG0066
Displacement: 0.662 cu in (10.85 cc)
Bore: 0.944 in (24 mm)
Stroke: 0.925 in (23.5 mm)
Practical rpm: 2,000-16,000
Output: 1.68 hp @ 16,000 rpm
Weight: 18 oz (510 g)
Includes: #A3 glow plug, 60J carburetor, #E4010S muffler
Recommended Props: 12x7, 12x8, 13x6, 13x7, 13x8

1QwkSport2.5r

None of the specs I could find stated the given weight was with or without muffler. I have a hard time believing the OS is 5oz lighter than the TT. 5 ounces is a lot of weight.

Sport_Pilot

Is that 1 pound 9 ounces? Or is that the time?

JPMacG

My Feedback: (2)

OS / Tower also recently discontinued the 10LA. They still have the 15LA, 25LA and 46LA. I suspect the 15LA's days are numbered and maybe the 25LA's as well.

aspeed

I don't have the .65's, but my TT GP .40 is one oz. lighter than the LA .40. 11.7 and 12.7 oz. (I think the scale was set for pounds on the previous post.) That was with the same muffler because the TT didn't have one when I bought it. They both run about the same rpm on the same prop. nothing special but basic and simple to use.

jeffie8696

I need to get my hands on another GP61 (its actually a .65) and do some testing. The first one I had was crashed hard and I think it had a bent crankshaft, didn't run too well.

aspeed

You can straighten the crank out sometimes. If worst comes to worst, you can cut off the thread, drill and tap a new hole and put in a stud after softening the front. It would depend if the drive washer interferes and if there is enough meat. You would need a lathe or a good buddy with one, and check to see if the drive washer is running true.

2walla

My Feedback: (10)

Power to weight wise the bushed motors are very hard to beat but modellers think they have to have ball bearings so the demand drops year after year. The only glow motors i still regurarly run are fp60's. Bulletproof...

Hobbsy

My Feedback: (102)

Here is OS' claimed weight for the .65 muffler


This is the Replacement Muffler for the OS MAX 60FP, 65LA, and 61FX Engines.INCLUDES: One Muffler Two Muffler Mounting Screws
FEATURES: Muffler has an adjustable exhaust port and comes pre-tapped.
REQUIRES: Muffler gasket OSMG6014
SPECS: Weight: 5.5oz (156g) Center to center of mounting holes: 43 mm
COMMENTS: This muffler fits the following engines: .60FP .65LA .61FX

jeffie8696

I sold the GP65 years ago as a parts engine, I think the bend was in the valve area and not repairable. I have quite a few 60 size engines now including a Kraft, K&B, Irvine.

loopdeeloop

My Feedback: (4)

I think electrics are taking a bite out of the 40 - 60 size engine market. That, and the fact that there are quite a few 4-strokes and small gassers in that niche means the bushing two stroke demand is likely way down. I'm not partial to any brand but there are lots of choices for 40, 46, and 61 engines. I have quite a few Magnum/ASP's and they have been excellent engines. Yes -- I also have a bunch of LA/FP engines but I will not lose sleep over them should they disappear from the market. I have a Super Tigre 90 that will go on a P-47 and I see that engine is no longer listed at Tower Hobbies. Also not a big deal because an ASP 120 four stroke is very little more money than the ST 90 retailed for.

rgburrill

I see that Tower doesn't list 40 size engines any moe but does have the ball bearing 61 size. No use competing with themselves - besides, Thunder Tiger beats the crap out of them for sport engines

1QwkSport2.5r

So the LA65 and GP61 weigh about the same. 25oz +/- with mufflers. Based on the other posts, the TT is as good or better than the LA on rpm and weight. Sure seems like a good or better replacement for the LA. And for the crowd that doesn't want to have to break-in an engine, there's no better IMO.

jeffie8696

I will have to get them side by side and do a comparison, perhaps the TT seems heavier to me because of the design. The color of the OS65LA just really goes well with my blue Escapade.

aspeed

The smaller LA .10's and .15's beat the crap out of the TT of the same size. Can't say for the bigger sizes, but the TT Pro .40 seems to have some lovers.

jeffie8696

I can attest that the TT46Pro is a runner.

bigedmustafa

My Feedback: (2)

I have owned and run a number of O.S. LA-series and Thunder Tiger GP-series engines. The .25 LA is a terrific little engine, as is the TT .28 GP. I think the TT .42 GP makes a better sport engine than the .46 LA, but I like the .40/.46 LA on trainers because the top rpms aren't as high as the GP .42. The .65 LA and .61 (65) GP are both terrific engines well suited to a variety of aircraft.

I am a fan of the Hobbistar Select RTF trainer that normally ships with the .65 LA on the nose. It is currently listed as temporarily unavailable, so it will be interesting to see if Hobbico updates it. Perhaps they'll bundle it with a lower-cost .65 AX like they did with the new Avistar Elite RTF and the .46 AX II? Only time will tell.

Maybe I'm getting pessimistic in my old age, but I'd be more likely to bet that they're simply getting out of the .60-size trainer market... such a shame.

jeffie8696

http://www.youtube.com/watch?v=uEB6RvOVONo
I am also a fan of the GP42 as well as the GP25.