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MT70CC TWIN

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Old 07-07-2011, 09:33 PM
  #1201
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Default RE: MT70CC TWIN

some twin ignition have programe problem( including DLE twin ignition during this year) and has been replace by RCEXL. and now quite numbers of MT70 and MT70S sold to Europe and have happy fly .
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Old 07-07-2011, 10:17 PM
  #1202
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Default RE: MT70CC TWIN

So that explains it
Faulty ignitions caused the bad bearing fits, poor machining, junk inside the crankcases and unreliable mechanical issues.

Thanks for clearing that up for us Tomy. We are really looking forward to having superb engines from you in the future now that the ignitions are sorted out.

Can we retrofit the new ignitions to the MT57 and the MT42 also? maybe they will solve the problems with those too.
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Old 07-07-2011, 11:07 PM
  #1203
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Default RE: MT70CC TWIN

i can only ,figure by that info,,that just the people from english speaking countries got the defective ones,mine wasnt real bad,but wasnt correct either,so i can only assume all the dialog here has been for nothing,, as far as good advise goes to the manufacturer,,and all we can come up with is ,,the ignitions were bad? mine still works fine,,and did so when my mt70 cc leaked oil ,and even when i attempted to use the leaky new version case,,with the crazy cylinder fasteners,,so in the terminology being used ,,,,,,,i had happy fly,,,after jody  went through my engine,,and also after novayusa  sent me a correct canister for the size engine,,the one offered  choked the engine to death...oh well ,,to be honest i think tommy may have been  making an attempt to make us aware of mld,s poor ignition,,,but he should have been addressing his own companys issues...........
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Old 07-08-2011, 03:43 AM
  #1204
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Default RE: MT70CC TWIN

Thanks for you are happy with the canister. Being long time not come here to read this thread because of busy with new type of header of canister,26-35cc canister and full series of pitts muffler(20cc, 30cc, 50cc)
wish you guys happy always with your flight.
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Old 07-09-2011, 12:21 AM
  #1205
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Default RE: MT70CC TWIN

How sweet this thread has become

It is a happy ending and don't we all just love those "Happy Endings"
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Old 07-09-2011, 02:39 AM
  #1206
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Default RE: MT70CC TWIN

Steve, where have you been?? Emailed you a couple of times and no answer. Wrongway was trying too.
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Old 07-09-2011, 06:24 PM
  #1207
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Default RE: MT70CC TWIN

Hi 72
I had a few issues to sort out. I spoke (by e-mail) with Richard over the past couple of days.

Got the small Yak flying (MVVS 26 on a pipe, C of G set at "Wild" and it is indeed Wild - recognise the basis of the covering scheme?), the "50" is under build (still) - I took a break from RC for a while due to some other things. and I have still got the "80" to build. (HTe 50 is getting an MVVS 58 in it - should be insane, the "80" is getting an MVVS 80 Twin spark - should be even more insane.

Anyone want a top of the range large profile plane? Wrongway RC - Wild Fred Laminar Yak.

I wonder how the 50's would go with one of the good 70 twins in it - .
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Old 07-09-2011, 06:39 PM
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Default RE: MT70CC TWIN

Glad to see you back in the game!
My Lambok has flown and was doing quite well until I had a battery switch problem, which caused a power off (optokill) fairly straight in crash. The fuse blew apart all the way down the middle but the tubes did not break. The wings were damaged from the tip to about 4 ribs in back to the spar. I have since rebuilt it and it is I think flying better than before.
I am just waiting to see if Jodi can get my mt70 up to his standards and then you may see a 70 powered Lambok!!
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Old 07-09-2011, 06:55 PM
  #1209
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Default RE: MT70CC TWIN

From what I have heard about the flying qualities of the Lambok (I have only heard good things about them). the 70 should be pretty much perfect on them. I know the DLE 55 is a great match and I am a huge fan of insane power on Profiles so I hope Jody can sort it out for you (If he can't nobody can).

Are you listening to this Tomy? - there is a market for your product - you just need to make them consistently good. See that photo I posted? It is the "small brother" of the plane we are talking about - imagine those showing your engines to the world.

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Old 07-09-2011, 07:02 PM
  #1210
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Default RE: MT70CC TWIN

That's the problem Steve. History has repeatedly shown that a couple of good engines are what start the sales trends but those fall off shortly thereafter because quality and consistency was never addressed. Ther's such a repetition of this activity with each new engine line there's little hope that change might be coming.

If the man had the ability to change his business model just a little bit he would be a raging success. The problem is that he is so consistent with failing to look after quality you might think it was intentional. he had the opportunity to be 10 years ago what DLE is today, but that path was not chosen.
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Old 07-09-2011, 10:55 PM
  #1211
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Default RE: MT70CC TWIN


Quote:
ORIGINAL: 72

..... I am just waiting to see if Jodi can get my mt70 up to his standards and then you may see a 70 powered Lambok!!
Unfortunately it's not quite that simple. The engine you sent did not come frommy shop, it was purchased from either Tomy directly, MT EnginesUSA,or one of the few otherresellers that just sold them as theyreceived them. A great many of those engines (notvery manyin total number) had/have "issues", they will run and run quite well but will not performorlastto their potential. Your engine has a few of the typical problems Ifound in almost every MT70 I was sent, all contribute to it's lack luster performance compared to the MT70 engines that left my shop. It has a crooked prop hub,incorrect ignition timing,leaking crankshaft bearings, and worst of all a mismatched pair of cylinders that provide a large difference in port timing between the two. The engine runs fine with about the same power as a DLE55, vibration levelsare higher thanthey should be, and the crankshaft mainbearings won't last very long once the rest of the grease pack leaks out. All of this can be corrected but not as inexpensively as other more consistently produced engines, we'll talk about that on Monday.

All of these problems and more wereevident in the first batch of engines we were sent, there was no way I could sell them that way. Ifound that the engines could be disassembled and by test fitting parts together I could assemble engines with good fitting parts that worked as they were supposed to. Among other things, bearings with the correct grease pack and seals were used, hubs were correctly installed, cylinders and pistons were matched together, carburetor adapter plates were surfaced flat preventing their inherent leak, engines were thenCLEANLYassembled with care and marked for future identification, all of this was done on top of paying full price for engines that were supposed to be "ready for use". The result was a relatively smooth running and very powerful twin for it's size and intended purpose,30% sizedaerobaticplanes.

TOMcan vouch for this engine's potential in that size airframe, it flat out crushes a DLE55, the one on my GW MX-2 spins a Xoar laminated 23x8 at over 7500 RPM on 1/4-32 spark plugs and stock exhaust.
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Old 07-10-2011, 04:29 AM
  #1212
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Default RE: MT70CC TWIN

I was quite impressed with what Jodi did with the MT 70, and what the engine would do in a 30% plane. If there's such a thing as too much power in a 30% plane, the MT/VV-70 fits that condition. I just renamed that engine Jody. I figure you did the work that makes it right so some credit should be given in the name
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Old 07-10-2011, 06:26 AM
  #1213
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Default RE: MT70CC TWIN

Jody,
Have you ever given thought to buying the parts in bulk and assembling the engines for VV? The MT70 has the potential for being "the engine" for 30% planes......most on here acknowledge that, so there is a "market". I don't know all the "ins and outs" of dealing with the china parts market, but from what has been said on here, it's possible. The "low cost labor force" needed for assembly is available here in the states and is under utilized....they're called "college student summer hires". There are plenty of colleges in your area with engineering programs. Most of these kids would jump at the the chance to learn from a master rather than "flip burgers" for the summer and it gives you the chance to pass on some of your wealth of knowledge. We use them at our NASA facility with great success. I've taught Voc-Ed classes at night at the local Community College for 30+ years and there are some students that you wouldn't trust with a screwdriver, but there are a few that have the drive and "know how" to be an asset and....... you get the satisfaction of seeing "the light bulb turn on" when they use the knowledge you've given them with success. It's a great feeling. It's too late for this year, but next spring, just email the HR departments at the colleges, tell them you want resumes and they'll jump on the chance.

Just an idea.....

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Old 07-10-2011, 07:07 AM
  #1214
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Default RE: MT70CC TWIN

Either that or convincing Don Lin to do a DLE 60 twin. That my friend would be a sweet engine if it was ever built. With it being smaller than the 70 in size it may not have the power though. I bet it would be on par with the 55.
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Old 07-10-2011, 07:40 AM
  #1215
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Default RE: MT70CC TWIN

Somebody started a thread about a DLE 60 twin and was flamed heavily. No market for it. Just a poor mans option. The consensus was it would never happen. I sure would like to have one though.
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Old 07-10-2011, 08:12 AM
  #1216
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Default RE: MT70CC TWIN

That's why DLE won't do a 60cc twin, it would compete with the engine that put them on the map. They would also have to change the cylinder so it would fit into 30% planes without the plug caps sticking out.

I have thought about buying the parts and building the MT70myself, last year that option was not available from Tomy but he seems receptive to it now. There are still a couple of changes I would like to makeso it's a bit more user friendly to set up, possibly a different carburetor, there are alsoother things in my personal life that could prevent me from doing it, I won't start it without being able to commit to it for the long term. I know the engine will survive at least most of the users out there, I've tried to kill the one in the MX-2 for over over 4 months now and the one in my Yak 55M for over a year. Endurance runs of 6-8 hrs straight with full throttle applied for 1 hr. nonstop, mountedon a test stand with no cooling but the prop blast, a 10-12 minuteflight at full throttle is a cake walk. Want to warm up an engine, the MX-2 will do a static knife edge spin without loosing altitude at full throttle, my Yak 55M an upright flat spin,tryeither of those maneuverswith any other engine for3 minutes straight, multiple times,might need a chisel to get the piston out.

Oh, and you better have pinned the firewall, trust me.

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Old 07-10-2011, 08:21 AM
  #1217
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Default RE: MT70CC TWIN

Jodi,

I just got 3 new Zoar props from VV last week thanks for the great service. I placed the order on Saturday an even with the 4th of July holiday I received them on Thursday here in Pa. Also since you drilled them for free it was out of the box checked the balance on the plane off it went. That's a great added value.
One of the props is for my MT70. I'm going to try a Xoar 24 A3D. I'm using a Xoar 24x8 beech wood now and the mt 70 turns that at 6500 RPM. I'm running a 2to1 header and a mt 65 lx canister.
I got an engine from the first batch from Tomy this was be for you where sending them out. I was one of the lucky ones this engine runs really well.

The front bearings leaked grease out for some time but now it's just a little oil. I would like to ship to you for a good look over and to change the bearings. How long do you need for this type of service.

Thanks Mike


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Old 07-10-2011, 08:33 AM
  #1218
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Default RE: MT70CC TWIN



It'll handle the 24-3DA fine, were running one on a GW SU-26 Honda scheme with the 70, it's turning it at almost 7000. I prefer the very snappy response and straight line speedof the 23" prop though, just my preference. I have a 22x8 3 blade that I like a lot too, I've just been to lazy to cut a spinner for it. If it's one of Tomy's headers you would do better by not using it, I tried it with half a dozen cans including the one you mention. It seemed ok on the ground but flight performance was poor compared to the stock exhaust. I might try a pair of 30cc sized cans in the future just for grins.

A little bit of two stroke oil leaking through the bearings isn't quite enough lubrication, I suggest they be changed. Turn around time right now is about 1 week.

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Old 07-10-2011, 08:59 AM
  #1219
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Default RE: MT70CC TWIN

Im hoping the 3Da it will run up faster then the sport prop 23x8. When I changed over from stock exhaust to the can Tomy convinced me to try a 24x8.
The engine is just way to loud to fly where I live with the stock exhaust. I have a small landing strip next my house and a lot of semi opened land but there are some homes a bout half mile away in a little valley with the stock exhaust i was not making friends.

Thanks for the info can I just send the engine out to V V or should I call first.
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Old 07-10-2011, 09:37 AM
  #1220
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Default RE: MT70CC TWIN

No need to call first, http://www.valleyviewrc.com/estore/m...structions.pdf
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Old 07-10-2011, 10:37 AM
  #1221
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Thanks
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Old 07-10-2011, 01:22 PM
  #1222
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Default RE: MT70CC TWIN

hi mb,,,long time no hear from,,,,i agree that the c65 canister does greatly reduce db levels but ,,is raher restrictive ,,and causes less power to be developed ,,,i had adressed that with novayusa ,,and he actually made me a canister with 2 outlets and moved the inlet to the other side of the can to allow a more straight in ,connection,but even that does not allow the engine to breathe as well as the stock ,,exhaust divertrers,,i cant describe them as mufflers ,,,,,im no tuning expert ,but im thinking if you could remove that little exhaust outlet on your c65 and have a larger one tig welded in ,,you may see better performance with little db gain, just tossing my 2 cents in for whatever it may be worth.but it does in a way back up jodys statement on the stock setup ,,if your setup is acceptable for you ,,and your are willing to accept the trade off,then leave that the way it is .
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Old 07-11-2011, 04:42 AM
  #1223
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Default RE: MT70CC TWIN

Hey unit,
Hope all is well, Thanks for shearing the two outlet can idea with me. I don't think I need any more power out of my mt 70.
My plane hovers just a little past idle and pulls out of a hover very fast doing snaps on the to the open sky.
I'm going to send my Mt70 in to valley view to have the case bearings changed out and ask Jodi to give it a good look over and address any other issues it may have.
I did give the 24x3Da a try last night and it ran up to 6900 RPM. I liked it the engine ran up a little faster and when in a hover it was turning more rpms and did not always want to fly away and was easier to back down with a little rudder.

I have a BME 115 with two MTW 75 h cans and it is some much less noisy then the MT its like night and day.

I may have to pick Jodi's mind on putting two 30 size cans in this plane to see how it change the noise and power.

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Old 07-12-2011, 04:44 AM
  #1224
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Default RE: MT70CC TWIN

two sets for MT70. as quite as MTW can.
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Old 07-14-2011, 05:11 PM
  #1225
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Default RE: MT70CC TWIN

Jody,

Do you have any parts for the 70?
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