I am looking to buy a gas engine but i am not all that familiar with the engines out there. The ones i know of are Brisson, DA, Zenoah, First place engines, 3w, Bme, and Zdz. Is this about all of them are did i miss some?

How do these brands compare to each other as far as power weight and reliability?

Why does the Bme use a single bolt prop hub while most of the other us the other type of hub? I am most intrested in the single bolt hub because its easier to mout the prop.

Can the others be converted to single bolt hubs?

Thanks

Grant

Hey Grant, the Brison (exellent choice, BTW) is a single bolt hub, also.
But here's my 2cents.
Buying or not buying a engine based on how the prop mounts is just plain wrong.
Please reconsider.
If that's your primary consideration when purchasing your engine regardless of preformance, customer service, and reliability, that's your choice, but I hope you adopt a few more critieria.
I have a engine that use a single bolt, and a DA that uses 4.

I love both my engines and wouldn't get rid of either one, but the way the prop mounts hasn't even been remotely important.

I am in favor of a single bolt hub. I don't have a lot of equipment available and for me, I need a straight hole. I am lucky that when I purchase a propeller from Airwild, it is the correct hole size for my Brison 3.2 and I don't have to do anything. I have ruined several propellers by drilling the holes in the wrong place. Here again, I am not the most mechanically inclined person you will ever see. I can understand the theory, but application I know is my shortcoming.

BRISON ! nuf said.

The main question here should be what size plane you will be putting the engine on, and what you will trying to be doing with it. There are a ton of choices available, and you should really define your performance needs before picking one brand of engine over another.

grant-RCU

I am still a bit new to gas engines myself in that I am on my second gas engine project, so I can really appreciate your question. Keep this in mind when considering my opinion, but I will add some things I have learned, which you may find helpful.

I agree with Kris^ in first wanting to consider what airplane you are going to be mounting in. You will also want to consider the options of going with electronic ignition vs. an engine with a magneto generated spark. Electronic ignition provides a hotter spark and in many cases makes engine starting easier. Conversely, an engine with a fly-wheel usually runs a bit smoother than one with electronic ignition. You will also find that weight varies a good bit from engine to engine. Make sure you consider total weight when doing a comparison. Include things like the muffler, electronic ignition (if applicable), battery packs required, etc. Don't pay much attention to HP ratings. These are usually very misleading. I have often heard it said, there is no substitute for cubic inches.

BackAfter30 mentioned performance, customer service and reliability. These are very important when making your selection decision. The gas engine market has really seen it's popularity grow in the past few years. There are now several quality name brands out there. You can just about pick any of them, based on the criteria mentioned and not go wrong. DA is known for their customer service, which being new to gas will be important to you when you have questions.

I also agree with Geistware in that a single prop bolt does make mounting easier. You need a drill press and a prop jig to drill a multi-holed prop. Even with these you have to work the holes a bit to avoid any binding, and it just takes more time. IMHO the only real benefit I see to a multi holed prop is that it looks cool :-) Maybe there is a safety issue with multi bolts, which makes sense, but my single bolt prop never came loose. I have had both and found the single bolt is much easier.

In summary, the criteria I would use would include the following. Size of the engine (cubic inches)required for the airplane being considered. Go to the high end of the scale vs the lower end. Carb location and cowling room for mounting. Total weight, Ease of starting, reliability, customer service, history from other users - RCU has a wealth of info on just about any engine. Cost, and in the end what you feel you want.

Don't be afraid of electronic ignition. I was at first and went with a mag. generated spark. I have electronic ignition on my second engine and it is easier to start. Good luck and I hope this helps you.

DA - all you need to say!!

jongurley - LOL - Yep!

OK, I tried to be objective with my advice, to some extent somewhat.
If I were to spend my hard earned money today, on another 50cc class engine NIB, it would be the DA~50 without so much as a second thought.
Everything about my experience with DA has been unlike ever before, first class treatment every step of the way starting from the first phone call.
And FWIW, DA gave me the prop jig at no charge.
Furthermore I drilled the prop on my lap, with a hand drill the first 2 times I drilled my props. Both came out perfect because as I drilled one hole, I filled it with a bolt, easily aligning the prop jig.
Total time for 2 props drilled in my lap was 30 minuets.
No big deal.

Sorry for the sales pitch, but I tried to be objective.
BTW I do love my Brison 3.2, but I bought it used, for substantially less than new.

Drilled the prop in your lap?----------
Didn't your mom ever tell you about safe use of tools -or loss of YOUR tool?

Yes Mom, (I mean Dick)
Believe me I thought twice about mentioning that, but it is what it is. Not safe, not smart, but at the time I was just trying to figure out how to best drill the prop when it hit me..the first hole was a piece o cake...then this idea of the bolt came to mind how to best locate and hold the jig steady...then another and so on.
I am not recommending to do it my way, but it worked out just fine all the same.