anyone know where I can buy a ASP/magnum .80? Hobby People are have them on back order. Also, I have a ASP 80 with a APC 12X6 prop should go higher? And would i be able to go higher on my vertical?

I run a 12X6 on my Magnum 52 four stroke. I would think your engine would happily turn a larger prop. How much vertical you get depends a lot on what you have it attached to.

You might try a 13x6 or 14x4 prop - I have used both of those sizes on my saito 72's depending upon the airplane.

Props that I use are:
12x6 on a 61
13x6 on the 70's
14x6 on the 91's

I would think that a 12x6 would turn 11000+ RPM on an 80.
Just guessing but the 80 should do well with 13x8 and should be loaded between 9000 and 10000 RPM.

I flew a Sig Midstar for a whole summer with a Super Tigre 40 and had nearly unlimited verticle. A 70 mag or OS is about as heavy as a saito 91. That kind of power on that plane would be entirely too much fun. I would think one of the new Saito 62's would be just right on a midstar.
Fred

i run a 10 x7 or a 9x8 on my magnum 52 XLS in one of my speed planes. runs great.. my idle was very inconsistant. but that was due to the high end needle not being tight so the vibration would make it tune itself lol. these engines love the Rpms. and tend to enjoy to run slightly leaner.

magnums in general i enjoy. havent had a problem with 1 yet.. they dont usually have the power and do weigh more then other engines of the same size. but the price is right for fun flying lol. im currently flying 13 planes and 5 have magnum engines. and have no complaints so far.

I've been flying a Magnum XLS .52A 2-stroke for two season now. I had two issues with it when I first broke it in:

1) The remote needle valve assembly was leaking air, so I just moved the needle valve to the front and bypassed the remote assembly
2) The muffler bolts kept shaking loose and falling out, so I bought some blue lock-tite to secure them.

With those two minor annoyances out of the way, the engine has been running wonderfully ever since. My experience with my Magnum 2-stroke gives me no resevations about recommending Magnum 2-strokes at all.

I also purchased their RFS .52 and RFS .70 4-strokes from my LHS during the sale. They are both for projects I haven't finished yet, but I'm looking forward to trying them. I have an O.S. F-type plug and a Fox Miracle plug to try in them so I can see if the F-type plug is worth double the money that the Fox Miracle sells for.

I own O.S. and Saito engines, and it's funny to realize that cheap engines can run great while expensive engines can still be worth the extra money. The higher quality fit-and-finish aspects of the premium engines are sometimes subtle, but there are just minor considerations with cheap engines that you don't have to worry about with the more expensive models. Both will fly your airplanes very well, however.

Thanks for the suggestions. I did fail to include the type of plane my ASP 80 is attached to. Right now it is on a profile plane called the Radical 330 40 - 46 size 2 stroke or 52 4 stroke. The Engine when i remove the glow plug always drop in RPMs by at leaset 200 - 300 rpms and in the air it has a tendency to lean in and out while airborne. any suggestions?

If your RPMs drop when you remove your glow ignitor, it could simply be time to replace your glow plug. If it is doing that with a new plug, I would try switching to a hotter plug than what you're currently using or trying a 4-stroke glow plug like a Fox Miracle plug or O.S. F type.

If your engine seems to be "spontaneously retuning" while in the air, this could be one or more of several possible problems. This could be caused by less than ideal backpressure to the fuel tank, a wandering needle valve being turned by vibration, a less-than-ideal fuel tank/fuel line setup providing inconsistent fuel flow, or all of the above. Try working through each possibility as thoroughly as you can and eliminate them one by one.

The glow motor forum here at RC Universe is full of very helpful folks with decades of experience with regard to sorting out issues like these:

http://www.rcuniverse.com/forum/forumid_114/tt.htm

Do any of you guys have any expreience with the larger size Magnum engines? (1.20 and 1.80 four stroke)

I have a Seagul Super Sport and it calls for a 1.20 to 1.80 two or four stroke. The Magnum 1.80 is $349 and the OS 1.60 is $299. I am undecided as to what engine to get for this plane. I do have three OS 1.20 AX's and love them. This will be my first experience with the Magnum, and my second with a four stroke should I decide to get the Magnum 4S versus the OS 2S.

I am not sure about needing the additional weight. I do need it on my Tiger 120 which is terribly tail heavy (through no fault of mine) and the extra nose weight would be a definite benefit on that plane, however, I am not sure about this Seagul Super Sport.

Any suggestions or opinions would surely be appreciated.

DS.

I have an ASP 80 that seem to have lost compression. How do you go about adusting the valves. I have ran about 3/4 of a gallon through it. Before this it ran great.

I am building a Seagull Super Star. It calls for 1.20 to 1.80 two or four stroke. I looked at the Magnum 180 four stroke, cost $349.00 and the OS 1.60 two stroke at a cost of $299.00. The OS has more power and, well, it's an OS.

I have three OS 1.20 AX's: one on my Venus II, one on my Excelleron 90, and one on my Tiger 120. All run just great with lots of power, running a 16-8 prop on all of them, turns right about 10,000 RPM, slightly under, actually, and I get clear power verticals on the two pattern planes, and good performance on the Tiger 120.

I would assume that the OS 1.60 will perform equally well and adequately for this application. I am going to turn an 18-10 prop on that aircraft.

I was really going to go with the Magnum 180 four stroke, but my experiences with the OS 1.20 and others that have used or are using the OS 1.60 were all positive and I don't have much four stroke experience (almost none, in fact) which really tempered my decision.

DS.

Download the Magnum four stroke manual from this page
http://www.hobbypeople.net/gallery/210945.asp
Valve adjustment is on the last page. The .80 adjusts just like the .70

Fellas!
Just went through cleaning of my old XL52 magnum 4-stroke engines . However can't find my manual. Does any one know what the clearances should be on valve adjustments Thanks?

I thought most all of the 4-stroke glow engines recommend valve clearance between .004 and .010 inches...