Larry, I own a BME 102 and I just sold my ZDZ40. I actually prefer a single bolt hub on a small gasser. My 102 is also a single bolt and I have no trouble at all with that. The prop may slip on some motors if you don't tighten it properly or use a spinner backplate with insufficient knurling. As for multi-bolt hubs...Do a search on prop bolts breaking. Many people have experienced problems with that, although it is usually caused by bottoming out the bolts when using a thin or soft prop.

Bill at Taurus was asked about the multi-bolt hub and I believe he would make it happen if enough customers requested it.

Ralph,

You wanna bolt up that 22-10 Mejzlik I gave you on that G-62 of yours and publish some numbers for me? Saves a lot of arguements. If I had a 24" prop for you to try out you'd have it in a heartbeat.

As for the rest of it, until you've had the power available to do some wild stuff I guess you wouldn't understand the desire for it. I guess you could say that if I had to explain you wouldn't understand.

D.W being the authority that he is, I think I should likely defer to his better judgement. RTK, you know me well enough to know what I just said.

How about we compare the same setups ? take the mufflers/cans off both or put an equivalent exhaust on the G62....Never tried a pipe or can on a G62, might be interesting...

Since you are here Ralph (RCIGN1), (I'm the other Ralph) what will a 62 turn a mejz 22x10 at

Don't know, never had one...
A generic Mac's pipe on a G26 adds 1000 rpm....

I have a real sneaky feeling that if the mufflers are matched up, say a couple of wrap around Pitts, there's gonna be some red faces with the non-Zenoah owners.

Pipe the 62 and the situation will become even worse. Or better, depending on your perspective I have flown a stock 62 on a 28% Extra and it flat out smoked the DA in vertical. Period!!

The only sub for cubic inches is cubic money. Tuned pipe vs muffler. Same exhaust and the cubes will win.
A lot of folks forget HP is only a mathematically derived number, what counts is torque.

I've heard all the G62 jokes & comments...."paint it pink and put a curly tail on it"..."they are only good for warbirds that need nose weight"...etc. I've been watching the converted & lightened G62 threads with interest. I've never owned one, but they seem to last and are economical. I've seen several in use. The one I saw the most of was in a Godfrey Laser and he was only turning a 22x8.

Here is the chance to finally put all the rumors to a stop. Put up some real numbers. Give us the facts. How about some of you 62 owners run some Menz or MSC 22x8, 22x10, 23x8, 24x8 props. Do it open exhaust and with a wraparound pitts muffler. B&B style noise diverters and Zinger props don't count. Come on guys...go big or stay home. You are fighting for the reputation of the G62.

Chuck

With a little porting, the G62 puts out more than 1.5 additional HP over stock without the slightest weight increase.

Headkitted and converted to reed induction, it's a monster.

Bottom line - don't discount the G62 so readily. There is amazing potential in that engine waiting to be tapped.

Only problem with that is $$$$.
For the difference you can get a 3W 80, $675...
I'm not dumb enough to suggest that a G62 will match a 3W 80...Or any other 80

I guess the question I want data on is will it really match a modern 60? Or 58 or 55 or 52? Numbers only please. I really want to know. I am not anti G62...just misinformed by those that are.

Chuck

True - but good porting for a G62 is available for less than $100.

The 80 is a step up and always will be, but a ported 62 @ ~$350 for the engine and ~$100 for porting is a heck of a lot of bang for the buck.

The average person looking for a G62 can't find one for $350...If I send you one of my new 4 lb G62s can you get it ported for $100 ?
If it works we will get something going...

Hello Ralph, while neither I nor my shop do G62 porting (otherwise I'd just be shilling my wares with posts like I've made), I can recommend several porters who do simply top-notch work. I've used them for several of my personal engines and have been very pleased with the results. PM me if you'd like details, and I'd be happy to make an introduction.

As for pricing on the G62 new, perhaps the 'average person' should check my site

I guess I'm not average, the only 62 on your site was one for a scooter, about $450...

Look more closely

http://www.davesmotors.com/store/engines.html

near the bottom.

Found it, how much for a hub so it can be used on an airplane ?
Looks like yours don't come from Horizon either

If I had one in stock, I could get you a quote But at the moment, it's not a part I carry. What are they going for from Horizon et al?

I don't need hubs, I make my own...Horizon wants about $80..
That's just for the hub...the bolt and washer are just as ridiculous...
Prop test...G62...Altitude 6800 feet...Temp 55 degrees...Fuel 32-1 oil, 87 octane gas..TNC tach..No muffler..My ignition, timimg at 28 degrees BTDC..Tried more, no difference...
22-10 Top flite 6900
24-10 Zinger 6000
24-8 PK 6000
22-6-10 Zinger 7200
22-10 Zinger 6700
22-10 MSC 6300
22-8 Menz S 7300
23-10 MSC 6000
22-10 DynaThrust 7500
Readings when I lived in Phoenix at about 900 feet altitude were about 400 rpm more on the Zinger 22-10.
I have seen slightly higher and lower readings from different engines...

Update...Different G62, Zinger 22-10, 7000 rpm...Same conditions as yesterday..I would expect all the other numbers to be 300 higher, based on this one...This engine must have had more time on it and is looser..

Now if a certain individual was to obtain a density altitude conversion chart to graph the loss in percentage of efficiency at altitudes above sea level he might learn something. Also needed is the ability to understand that a 55 degree day at 6,800 feet msl does not fall within the standard lapse rate and is therefore at a density altitude considerably higher than 6,800. A rather loose temperature lapse rate for a standard day is in the area of 3-1/2 degrees F. for every thousand foot gain in elevation above sea level. The base line at sea level is 59 degrees F.

But first he needs to understand that a constant gain in altitude causes a constant loss of available oxygen for "sea level" I.C. engines to mix with the fuel, thereby reducing the amount of available power without the addition of a super charger of one sort or another. You can only lean an engine so far.

Far too many flying r/c have little or no understanding of basic aerodynamics which seriously and adversly effects their ability to understand why their planes do what they do, and why those same planes can be utterly predictable to do certain things at certain speeds and attitudes. An understanding of weather and the atmosphere provides tremendous insights into engine performance.

Pat

Here's a few more numbers to throw out there. New G62 on stock ignition, B&B muffler, 3 gallons of fuel through it and now on Stihl oil at 50:1. Broke in on 2 gallons at 32:1. Temperature was 50 degrees, I'm at 580 MSL. Needles are still just a tad on the rich side, but not burbling at all. Just not peaked. No needle adjustment was made between prop changes, and all props were flown for a flight to compare flight characteristics and engine performance.

22x10 Mejzlik 7350
23x8 Mejzlik 6750
22x10 Menz S 6650
22x10 Bolly Wood 6900
22x8(cut down 23x8) Bolly Wood 7050

I believe my broke in DA50 (31 gallons) turns the Mejzlik 23x8 at 6600, the 22x10 Mejzlik at 7200, and I only tried the Menz S 22x10 on it once when new and only got 6200 or 6300.

I had another G62 that had Ralph's ignition on it that was well broke in with 60 gallons, and it turned the same Mejzlik 22x10 at like 7600. The KS 1060 will go on the G62, but still haven't come up with a good header. My old G62 & Mejzlik 22x10 prop would hover the crap out of my 20 lb. Giant Stinger. I'd like to see what one would do on the new AW Yak coming out with the tunnel already built in. G62/Mejlik 23x8/tuned pipe/Yak @ 20 or 21 lb........

Well, I got my Yak today. Sooner than I thought. I'm going to be conservative. So 50cc is going to be the engine. This is my first gas plane and the biggest invesment as far as money is concerned. I'll think about excess power on the next one.

Thanks for the opinions, personal preferences, and thought provoking comments.

Mike

Glad to hear that you received the plane early. I'm sure you'll be happy with the 50.

Good flying,
Pat

These open exhaust and B&B "muffler" readings are approaching what a DA or Taurus will turn with a quiet wrap around pitts muffler.

I guess cubes really don't matter. It sure does not look like the mighty G62 likes big props at all. That's what these numbers say quite loudly.

After careful consideration and research, I decided on a Taurus 3.2

Mike