Hello,
When an engine company lists a weight on an engine, are they giving the weight with the muffler, or without?
Example, ys.45 is 14.11 oz, is that with muff?
Also who has the lightest .45 2cycle?
Thanks for the info!

USUALLY...the mfr will specify the weight of the engine in either configuration. USUALLY.

As for light .45's....

the Fox .45BB is 12oz.

and the not so light...

The OS 46FX is 16.5oz.

That's a QUARTER POUND difference for those keeping score at home. This sort of thing DOES make a difference!

Not totally fair to compare engines based solely on weight of course, but....it's something to be considered. The lighter the model...the better it flies.

Most will state the weight as being with or without muffler although OS give a weight that's without muffler and don't tell you.

The lightest ball raced .46 that I know of is the Stalker in either side or rear exhaust. With muffler these are 10.25ounces. They also have a new light version of their RE .61 which is supposed to be about the same. That makes it at least half a pound lighter than just about any other .61 engine!

Are the stalkers any good?
Where do you find them?

Just a note...

lightweight is a function of engine design to a certain extent.

An ABC or ABN engine will be heavier than it's ringed counterpart because the brass liner is heavier than a steel liner.

4C engines are heavier than 2Cs because there are simply more parts.

Construction differences factor in. When you make things thinner...you are using less metal...hence lighter weight.

Use care...some obscure engine that is "the lightest" is not necessarily the be all and end all of model engines.

Make your choice on performance. If there's equal performance to be had...THEN go to the lighter engine.

Soybeans are sold on weight....engines aren't.

Most manufacturers give weight with and without the muffler. However, the weight does not include the prop washer and prop nuts. I weighed each of my YS and OS engine without prop washer and nuts using a precision postal scale, and each engine ended up being the same weight as what the manufacturer claimed. However, when prop washer and nuts were added, each engine turned out to be 0.1 - 0.2 oz heavier.

Splitting hairs Rich? <G>

Yep, splitting hairs. Sometimes .2 oz of lead can throw off your balance

On a peanut scale....<G>

Racecity,
I dont know about 4 strokes being heavier than 2 strokes.My 61FX is more than a 1/4 pound heavier than my 91 Saito

Interesting...

Then again...the Saito is built very "lightly". I've seen three owned by club members that have actually sheared off the cylinder in a crash.

Pretty lightweight construction....that's why!

Great engines...don't get me wrong...but the light weight carries a price.

An ABC or ABN engine will be heavier than it's ringed counterpart because the brass liner is heavier than a steel liner.

I don't think there is much differance, though brass is gold colored, it doesn't weigh as much as gold.

4C engines are heavier than 2Cs because there are simply more parts.

Most manufactures show weight without mufflers. Most 2 cycles are lighter than the equal powered 4 strokes if you show weight without mufflers, but heavier with. Although some of the newer mufflers made of rolled aluminum tubing are much lighter than the older cast ones.

I don't know why, but seems that manufactures that make both 2 and 4 stroke engines have heavy engines. Seems that manufactures that make just one type make light engines. Saito only makes 4 strokes and they are light. Fox just two strokes and they are light, same with K&B, Webra, and others. An exception might be Rossi who make heavy two strokes, but they are also very powerfull.

Hey Sport..

My figures are coming from weight WITH and WITHOUT mufflers.

Are you arguing that 4C's are heavier? They are.

ABC liners are in FACT heavier than steel....pick one up...measure it some time...come back to me on that.

??????

A typical equivalent powered 4 stroke is lighter than the equivalent powered 2 Stroke with mufflers, but there are many exceptions.

A brass liner is thicker and heaver than a steel liner. Especially in older engines. However the weight penality is not very significant.

A TT91 fourstroke weighs 25.3 oz with muffler
-TT pro 61 weighs 26.75 oz with muffler

A OS 91 fourstroke weighs with muffler weighs 24 .75oz
- OS 61 FX weighs 24.3 oz

Saito 100 with muffler =21.25 oz
Ys63 FZ with a Saito muffler=18.13 oz

The Saito and Ys are lighter and more powerful than all the other 60 size 2 strokes in Dave Gierke's 60 size engine test in the May 2003 MAN mag
The popular fourstrokes around my neck of the woods are not heavier than the popular 2 strokes.

Sportpilot,
2 stroke mufflers are way heavier than 4stroke mufflers

RaceCity,
You list the Fox as 12 oz , is that with a muffler?

Most .60 sized engines are not equal in power to a 4 stroke .91 these days. You may have to compare .75 2 stroke weights to compare apples to apples.

Spaceman....yes, the Stalkers are very good but quite different to the usual RC engine. They run somewhat like a 4 stroke in having high torque at low revs so if you buy engines based on HP figures then it'd be very low on your list
But if you want to swing a big prop at maybe 11K and save half a pound of weight.....

Down, where do Stalkers come from, I have some Mercos that are low rpm torque engines. I happen to like that kind of engine. They fly planes just as well as hotrod engines. Mercos work best if propped for about 8,500 rpm.