I'm getting a BME 30% Yak in a few weeks. What engine should I use? I was thinking DA50 or MVVS 45cc.
I've heard that the DA50 "burbles"?? I 've heard the engine and I must agree that it seems to make a missing sound or a burble sometimes. But I also hear that they (Desert Aircraft) has the best service. But i can't find any in stock. DA says 3 to 4 week wait.

I've also heard of nothing but good things about the Mvvs. Powerful, reliable, light weight. In stock available for immediate shipment.

I need sojme advice from people that have experience with these engines.

Thanks in advance
Mike

Note: Let's not turn this into a whizzing contest guys. These are my opinions.

I also looked at DA and MVVS/Evolution 45. I have no doubt that the DA (I've made offers on two this week here) is a fine product with some of the finest customer service you could ask for.

Think about a Taurus TS52. I like the idea of a double web crank and a bell mount included (no standoffs required). Do a search on the internet and see if you can find one bad comment and then decide. I went through the same process and have one on order. Taurus had a price increase in December but it is still a good value.

Here's the process I went through...

MVVS (Same as Horizon's Evolution 45GX): Not much history

DA: Most history of any late model 50cc. Mostly good reports, but the one I see at our field is still not dialed in and I have heard about the mid-rangle burble/deadstick issue a lot as well. Granted, these may be user related problems and DA will back what they sell. I personally don't like 2 or 3 inch standoffs.

Brison: Good motor! I owned a 2.4, but there has been some changes at Brison...

Fox & FPE: I don't know. To me they look like a Brison copy.

BME: I hate beam mounts on a 50cc motor.

ZDZ: Good for some, not so good for others. I had a 40. Do a search....

3W: I seriously thought about the new 55! I have not heard any user reports yet and all I could get from AA was cannister data.


Here's one of the Taurus threads http://www.rcuniverse.com/forum/m_35...tm.htm#3570123

First, go with a 50cc plus, not a 45cc. More aircraft options later.

Second, there are a lot of great engines out there in this size range. It will come down to fitting your budget. Fox, First Place, Brison, BME, 3W, Taurus are a quick few I can think of, and not necessarily in that order.

Third, that "burbal" you hear about is directly controlled by the needle settings input by the user, and the stage of break in the engine is at.

I agree! Some good advice from Silversurfer. RE: His third point...For every complaint I read about the DA... usually twenty or so guys wrote in and said theirs were awesome. I think the user was a factor, or perhaps the break-in was not that far along.

I think DA and Taurus will tell you the wait is about 3 or 4 weeks.

I fail to see what the stage of breakin has to do with a burble...I agree with the needle setting, too much of the "I haven't touched the needles yet" syndrome.....

I put an Evolution 58 in my 30% yak it has tons of power. It's like flying a big foamy.

Ralph,

With every new engine I have owned the required mixture settings for good running changed slightly during the break in process. Since I use only synthetics from the first run, the full process may take a smidge longer that "natural" oils. In any case, my mid ranges have always had a small "burbal" at those ranges until a few gallons had been run through and the final needle setttings had been obtained.

There's only one person that I personally know that has not had that "burbal" and he always leans the crap out of the enigne 'cuz he forgets which way to turn the needles.

Pat

Ouch Pat, I think that one was directed at me
This problem happens for the same reason that when my plane is up side down I still don't know which way to input for correct rudder output. I get disornemanted easily. I also hate an engine that burbles too much.
I do agree that the end user is the one that usually causes the engine to run poor.
There are many good engines out there that will fit the bill and all will run well if properly set-up.

bigtroutdog--When you order your plane why don't you ask if they have a package deal with the new 55 from BME. Just another option to look at.

I didn't provide any names to protect the innocent.[8D]

---------------


Fortunately, if a gas engine will still run, it isn't too lean. <G>

I agree, all engines will require some tuning as they break in and get looser...It's the pilots who never touch the carb needles until 4 or 5 gallons have been run through that have the most problems, and that's who I was referring to...
RTK is innocent ? Must be two RTKs
And Ed Cregger is also right, if the low is too lean it will never transition, and if the high is too lean it will quit before it gets to WOT...If you open the throttle and the engine gets almost to max rpm and starts to slow down, there's a message there, shut it down and richen it..
It's really hard to get one too lean to stick, but it can be done if you try hard enough..[8|
Or don't use enough oil []

Nah it wasn't that lean, just enough to clean the plugs I used a similar procedure when I was flying full scale to get a decent mag check after some banana head ran it too rich

Ralph, I know I must be innocent of some thing I just gotta be.
Plus I haven't cooked an engine in many many years.

RTK,

You left me more openings on your last than I know how to fulfill. Therefore You're getting away with it.....this time

I would think for a 30% a 45 or a 50 cc would be under powered.
Have you looked at the Evolution 58? That would really give your plane tons of power, it can swing a 26x10 @ 6000 rpm, and a 24x10 @ 7000[8D]

Ok the winner is.... nobody...yet.

This is my first gas airplane. The Mvvs 45 is supposed to have slightly more hp than the 50 DA. (5.2 vs 5.0)

So getting the larger displacement engine doesnt make sense unless it makes more hp.

I don't think either will under power a 16 lb yak. A friend has a TOC Yak with a 50 DA and it has awsome vertical.

Thanks for the opinions. I guess it's like what glow fuel to use. What ever you think works. If I could buy a new DA 50 right now

I probably would. Only because it's made in the USA. I'm not convinced either one of the two engines I'm looking at, is the better

choice.

I'll decide within the next two weeks. Maybe sooner since they shipped my Yak today.

Mike

Mike, just keep in mind that the MVVS does not come with standoffs so you will need to make or buy some. It is also designed to be run with a can. All bets are off if you use an in-cowl muffler. You might be down several hundred RPM, and in the giant scale gas world that is huge. On some of the Yaks you can put a can down the bottom of the belly if you cant the motor.
On the plus side...Horizon is already stocking parts for it.

Keep us informed. It's a big choice! Been there...still doing it!

Chuck

Chuck
Thanks for taking the time to help. The BME Yak has a canister tunnel. So that's not a problem. But I hear it's a pain in the ass to get everything lined up with the thrust lines etc. Mvvs has a engine mount available on their web site. So no stand offs. But no Pitts style muffler which would make the job easier.

I like the fact that DA has everything I need for installation like standoffs, mufflers, (or cannister if I want). Seems to be less of an issue . They just are'nt available. DA seems to be more of a popular motor so I can get help easier.

Thanks again
Mike

I'd go with a can. DA has wraparound headers on their site. Horizon also carries a Bisson muffler for the Evolution 45GX which is the same as the MVVS. If you are down to those two I think I'd lean towards DA simply because there is little data out on the MVVS. Yes I know guys say it turns this or that RPM with this or that prop...but for how many years? That was a factor in my choice.

Here's the muffler... Oops. Horizon updated their site since yesterday. They had a pitts on a 45 in a H9 260. Here's the number of it anyway: BIS05545 Inverted Wraparound muffler I have the picture saved at home. I'll post it later.

If it was me, and I had the money and could stand the weight I would go for the quiet power of the can setup.

Chuck

Here's the picture of the muffler from Horizon's site yesterday. They changed the site and I can't find the picture now.

I'm not an expert on gas engines. I only recently got my first one, an FPE 3.2 on a Sig Sundancer biplane. I love the engine so much that I just bought another one, a 4.2 Now I have to find an airplane for the 4.2 and I'm looking.

Anyway, the 3.2 is just so easy to crank, run, fly. The Sundancer is not a big plane, maybe 16-18 pounds but it is off the ground in no more than ten feet, if that much and it just zooms.

But I never read much about the FPE, it is not so popular as some other brands. Some advertise more than others and get more publicity while they appear to be the same basic engine. And everyone has his favorite, usually whatever he is flying.

The one engine that has impressed me the most (I've never seen one) is the Taurus. I've never read a single negative about it and the balanced crankshaft seems to make it unique among all the gas engines I have read about. And the manufacturer is a regular contributor to the forum...I think he truly is interested in his constituency and the way his product is received. The only thing I don't like about the Taurus is that the prop is bolted on, 180 out from the rest of the world....someday they'll change that.

Larry

I'm going to step off the beaten path with this one. You're starting baseline is 30%. Okay, great. You're looking at 45 to 50cc engines, but have started to move toward a 58. Again, great. Now the side step. Why not compare some weights and prices and consider a Cunningham converted G-62? Weight is inline with the 58. Power is probably equal to or better. Reliability is a lifetime given. I have no idea where Evo will be tomorrow. Price is comparable. Ignition warranty is lifetime with RCIGN. Later uses is higher with the 62. Availability is likely sooner with the 62. Getting full and easy access customer support is a high priority with the 62, not that yoy will need any.

My choice at 30% would go to the Cunningham G-62. It's quite a bit more powerful than the DA50, (quiet, DA owners) with no known reliability issues. The base engine has been in production for decades, making parts availibilty a non issue.

Pat

Silversurfer,

A converted G62 will not run against he MVVS58 any day or night, the mvvs58 will smoke it. A properly setup mvvs58 on canister swings a 26x10 @ 6000 rpm, 24x10 at 7000, it swings the 24x10 @ 6700 rpm on a Slimline wrap-around pitts DA-50 modified muffler.
The best the zenoah can do is a 22x10 @ 7200.

So no way will the zenoah 62 ever come close to the mvvs58 power, The mvvs58 with a factory canister weighs the same as the zenoah converted so its not any heavier either.


As for the reliability, price performance ratio, or any other factory, I'm not going to comment on that because I do know, however, if you wanted power readings, well their you go MVVS58 wins in this category.

Disco---A stock lightened Ralph Cunningham 62 with ignition is at 4lbs a stock 58 with out ignition is at 4 lbs. Where are you getting your numbers from? Or am I wrong?

Silversurf,>>> quote

" Okay, great. You're looking at 45 to 50cc engines, but have started to move toward a 58. Again, great. "

I don't think I said that I've started to move toward a 58. I'm going to stick with the 50cc range.

I have a VW in the back yard... why don't I drop a 454 w/blower in it.

How much power do I need? ? want?

bigtroutdog
I am not answering for Silversurfer, but it never hurts to have a little to much power. The excessive power can be controlled by the left stick.
I always shoot for at least a 2 to 1 power to weight ratio, helps me out of tight spots.