THE NEW MT 57CC ENGINE

[hughes500e]

	Quote: Originally Posted by Al Lewis
	From what little I've been able to read they are about the same so far. I still think the MT-57 would spin a bigger prop with a stiffer reed though. 24X10 or 26X8. That Xoar should give you good thrust. Don't you mean 23X8?? I use one on my smaller 43cc as Vess doesn't make a 20".

The XOAR dealer up here had no 23x8 props in stock so I'm checking out the 23A. Unless I read wrong with the stock exhaust I should be able to obtain 6800 to 7 RPM with good pull.

Here's a thought, with DL being new on the block perhaps they wanted the strongest running 50cc and marketed it as such. If we measure the actual displacement maybe...........

[jrjohn]

	Quote: Originally Posted by sinergy
	Al.. there have been no attacks on my part.. this moron just doesnt give up. I haven't even said one bad thing about the engine in the entire thread! However John you can say what you like.. consider yourself ignored.. I refuse to response to your useless posts anymore. Your name calling amounts to the intelligence of a 5 year old

Chainsaw,I never wanted you to respond to me. How about you ingore everybody and just go away, thats all I really ask. And yes, your right, I don't give up, and I'm not paid for my opinion. No sales team for me.

[Al Lewis]

	Quote: Originally Posted by hughes500e
	The XOAR dealer up here had no 23x8 props in stock so I'm checking out the 23A. Unless I read wrong with the stock exhaust I should be able to obtain 6800 to 7 RPM with good pull. Here's a thought, with DL being new on the block perhaps they wanted the strongest running 50cc and marketed it as such. If we measure the actual displacement maybe...........

I've checked the published bore and stroke and it's a 50. The key is in the ratio of bore to stroke. Just like the old 302 Chevy.

[robertp17]

is it oversquare al? lots of engines have a bigger bore than stroke, just curious if the dl does.

[soarrich]

	Quote: Originally Posted by hughes500e
	The XOAR dealer up here had no 23x8 props in stock so I'm checking out the 23A. Unless I read wrong with the stock exhaust I should be able to obtain 6800 to 7 RPM with good pull.

If it's a Vess 23a my tach said 7400rpm and 33 pounds 8 ounces of thrust. I haven't calibated the scale but the tack is dead on 3600 with a light. Now I wish I didn't throw my bowling ball away, finally a use for a 16 pound ball. Anyone know of something common that is a specific weight near 25~30 pounds?

I flew a 23A Vess the engine liked it, I just got a Xoar 23A, but I've only flown that on my Brillelli 366GT it was a great combo, quiter that the Vess I think, flown two weeks apart though, so I'm not positive.

Al
I'm hoping you scale is reading light, because mine would have been at about 32~33 pounds. Who would think it would be so hard to find a fish scale that gave a honest reading?

[wildhare]

	Quote: Originally Posted by soarrich
	Anyone know of something common that is a specific weight near 25~30 pounds?

You could take it to the grocery store and weigh a frozen turkey or a big bottle of detergent or a bag of dog food or something. There are lots of heavy things in a grocery store and lots of scales around to weigh things to double check.

The weight of the turkey will be on the label, but I'd weigh it on a couple other scales and double check the reading.

TF

[AJT]

I always use a dumbell for a cail weight! seems to be a good standard. I'm sure there are pleanty of dumbells around for use (LOL).

[soarrich]

	Quote: Originally Posted by wildhare
	The weight of the turkey will be on the label, TF

Cool idea, I'll offer to go shopping for the wife seeing it's Mother's day. Hey what a guy!

[Al Lewis]

	Quote: Originally Posted by robertp17
	is it oversquare al? lots of engines have a bigger bore than stroke, just curious if the dl does.

DL Bore & Stroke is 43mm X 35mm
DA Bore & Stroke is 42.6mm X 35mm

Rich sounds like that fish scale was designed for bragging rights. I want to take that one salmon fishing with me!! LOL Like Tom says, you should be able to get something weighed at the local market close enough to check it. One other thought is, if you didn't turn it on until after the engine was running it would zero at about 2-3 pounds too high due to the pull from the idling engine. These scales zero when you turn them on regardless of what's on them.

[soarrich]

	Quote: Originally Posted by Al Lewis
	Rich sounds like that fish scale was designed for bragging rights.

I checked it out, a 3.74 pound meat package weighed 3 pounds 12 ounces. A 36.4 pound battery weighed 36 pounds 7 ounces. That is less than .5% error, if there is any at all. I standby the numbers I posted 100%, they are accurate. The scale I have is a new Rapala 50 pound scale from BassPro on the web, it goes for about $30 to the door.

You want to take you DL's cowl off, hold your scale at crankshaft height, with 7400 rpm you'll get 30~31 pound thrust.

Tom needs a new scale. I'm sure if you hook a DA85 up to a Vess 23A spinning 7400 rpm without a cowl it'll make 33 pounds of thrust. I did all my test without a cowl like the picture showed.

[Al Lewis]

That's it!!! Everybody's scale is bad but yours! LOL It may be your process Rich. There is a formula out there for calculating thrust. You should try and find it and see at what rpm a 22A (basically a 22 X 8) would need to be to put out 30 pounds of thrust. Better yet ask Robert Vess. He's on here all of the time and I'm sure would be happy to help out. I don't doubt your sincerity, just your methods.

[soarrich]

Pe has a Microsoft Excel spreadsheet, you can download it yourself from his website, it said 22x8 7530rpm + 33.07 pounds of thrust, run the spreadsheet yourself. BTW his program predicts NX 22x8 7172 rpm for 30 pound of thrust. No Vess prop constant in the spreadsheet.

Tom said his scale is crap, and you're measuring your engine with the cowl on, that will lower your thrust, try it.

Enough arguing, have a nice life.