I just bought a new DLE 55 from Tower Hobbies along with the Reactor 1.60 (50cc). Everything was built and I was ready to start breaking in the engine... The motor started right up and had a good idle... When I throttled up to 2500-3200 rpm the normal vibration was there expected from a 50cc but when I went to full throttle the vibrations felt like a messager and looked as if the plane was going to vibrate apart... The prop and spinner is balanced, I even took the prop and spinner off my Ultimate with a DA 50cc and tried that prop and spinner and the same vibrations were noticed... My question is.... Would timing cause the bad vibes? Or would the crank be out of balance? I just want to eliminate all possibilities before I send the NEW engine in for waranty work... Any and all help would be greatly appreciated... Oh and by the way, besides the vibrations the engine runs great and transitions great from idle to full throttle and back to idle.... This engine is a Beast!

Did you have the wings on the plane when you ran the engine

I did have the wings on the plane when the engine was running... I would never run a gas engine without the wings on, LOL... The plane had wings attatched and bolted on, I checked the engine bolts to make sure everything was tight and everything was.... At full throttle the elevators, rudder and the trailing edge wing tips (both) were vibrating pretty bad... Its not a violent vibration at full throttle but rather a high frequency vibe to where you can see it vibrate and feel it and it makes your hands numb... As I throttle down the vibes go to a lower frequency where you can see and hear it vibrate more...

Rover1newton,

I just bought a DLE 55 from Tower as well. It will be going on my new Aeroworks S2 Sport Cub. Have you tuned the engine or just ran it with the needles set the way it came?

I'd check the firewall and engine box very closely. Make sure it's solid. I'd reinforce it if I were you. This is a one badass powerful 50cc engine. A loose engine box or firewall would totally make the plane shake. It needs to be solid. I good tune would help also. A rich low needle can really shake the crap out of a plane at low RPMs.

By all means, tune it first.... Beyond that, I'm with Joe on this...How long are your standoffs? Got any good pictures of the installation?

Right on! the DLE 55cc is VERY powerful... I actually checked where the factory had their settings on the engine compared to the manual and they were very close but I did put the low end needle @ 1 1/4 out and the high end @ 1 1/2 out and it fired right up, idled great and had good transition... The only thing I have encountered negatively is the vibrations... The vibes @ idle feel normal but throughout the whole rpm range there are bad vibrations... Some vibes are expected but these are NOT normal...

Yep, I am fully aware of the rich low end needle setting. It has a great idle and good transition from low to high and from high to low... The only thing is it vibrates pretty bad throughout the whole rpm range... It's not the shaking at low rpm i'm worrid about its the vibrations... There isnt an engine box per-say... All it has is a firewall... Check out Tower Hobbies and look at the Reactor 50cc and you can download the manual... The way they have it set up in the manual is exactly how I have it set up... The stand off distance is 3"... And everything looks to be pretty solid up front and no where close to being loose... Also, all bolts are RED LOCKTITEed...

Hey Rover, I got exactly the same setup, same plane etc. I don't know what it is about that airframe but it shakes that back end like no tomorrow. My hoizontal stab came loose on mine when I tested it for the first time. I've been flying this combination for a over a year now and I can tell you that it still vibrates (on the ground) when that motor is throttled up. I guess its fine in the air or mine would have vibrated apart by now. Never had a airframe vibrate like this one. The gear on this bird is very weak, if you have not done so do yourself a favor and get a carbon replacement. And, make sure all your servo arm screws are secured with silicone. The vibration on the back end will loosen them up over time. Fairly decent plane but its hard to see with that color combination IMO. Jerry.

Well, since you have the same set up and have had no problems flying it I guess I'll just fly it then... Must be the airframe configuration then... It is built pretty light... Did you re-enforce the firewall at all? Where did you get the carbon gear from?


Thanks....

I took it out of the box and ran with it, no additional reinforcements. I think I got that gear at TNT. If you look over in the 3D area or search you'll find a thread on this bird with all the details on the gear etc. Jerry.

Thanks, I'll check it out....

If you're concerned about vib's I'd at least pin the firewall with either socket head sheet metal screws or wood dowels and epoxy. I wouldn't want a firewall shaking loose and an engine flying out. It does happen. A light plane doesn't absorb vibrations very well. That thing will probably be a rocket.

Yeah, if it vibrates that much just because of the airframe I was going to pin the firewall with the toothpick/epoxy method and prob a few screws before I take to the air.... I was looking for the carbon gear for it but no one makes it for the Reactor 160... Is there another set that from a different model that fits it?

I mis-spoke(wrote), here is the details on the gear I used; copied from the Reactor thread on the 3D forum.
FWIW I used the Graphtech 120 #120 Hangar 9 33%/35% Extra 330 Main Landing Gear on my Reactor, I simply cut the gear down the center, used the originals to get the hole spacing correct and mounted them up. I also had to open the slots in the fuselage about an eighth of an inch. They work great, look pretty cool too. Cost me all of $35 on sale a couple of months ago. No more prop strikes during my less than graceful Harrier arrivals

I have the DLE55 mounted in an Aeroworks Proflie Extra 260. I used the standoffs that came with engine which are 2-5/8". A little vibration at idle but that's it. Is it possible that the engine is too far out from the model? There was a mention that the standoffs were used were 3". Just a thought.

Just an opinion on the vibration, The DLE55 has alot of compression and also with it being new (not Broke in) It should get better as it breaks in. JMO

Hi It does sound like you have a very light airframe there.
The best method to test if there is something amiss with the engine is to take it out and bench run it with the same prop. and spinner. and you can set the needles at the same time if it starts jumping about then the engine has a problem.
A good idea with all gas engines is to check the timing before flying its very simple and only needs to be done once, use a timing wheel there are a few posts around, some are a bit complicated but the timing wheel method is the simplest, yes i know its a bore to pull it out of the aircraft and set it up on the bench, but apart from that you could fly it to see if it falls apart in the air.

FWIW:
Go to youtube and look up your plane running while sitting on the ground. Everyone I have ever seen vibrates/shakes extremely. I believe when your engine gets some time on it, it may reduce some but not a lot with that airframe.

Glenn

If the vibration is excessive comparing to DA50, consider send the engine in.

I would not fly the plane if there is a vibration problem, especially at high RPM. You may end up destroy the plane.

a friend of mine has the same airplane, and everything and doesnt vibrate much. We did some fine tune and now is less than before, i recommend you to check:

1. firewall
2. standoff/screws
3. pick the low and high and check for good transition.

If you have already your propeller tips and hub balanced it shuoldnt be too much vibration in that airframe.

I put one more tank through the engine and the vibrations are taming down a bit, think since it has high compression and not broke in yet I will wait till I have a few gallons through it before I send it in if it still has the vibes...... So, I checked all screws, nuts and bolts and decided to take her up for the maiden flight.... I had the rates low and expo up a bit and she flew like a trainer, cant wait to see what the high rates will do...... The Reactor and the DLE 55cc is an awesome combo! Once I feel more comfortable with the engine I will start to ring her out like my .46 Reactor with a Saito .91.... Thanks for all the advice... I did everything everyone suggested except send the motor in... The timing was 30 deg...

Tune it right, balance the prop right, and mount it right. Then get back to everyone with the results.

I really don't know who you are, but it was built right, balanced correctly and TUNED! This isn't my first rodeo.... I've not had a DLE before just DA's and they do not vibrate like this one has at mid to full throttle.... All I did was raise a concern to see if someone else has had an issue like this on a DLE 55... So, when you can give someone some good advice and know what you are talking about then post a reply... Other than that keep your posts to yourself...... It amazes me that some people go around posting crap like this, seems to me that they don't have anything better to do..... Thanks for all the help from the ones that were trying to help.................

Just bench run my DLE 55, planed to be installed in the Reactor and it shakes like mad in mid range, tuned carb but did not get any better. I am afraid it rattles the Wings of that Plane. I check Timing and behavior later, if not i switch to a different Ignition and let you Guys now at a later point. I deal a lot with Gas Engines and it seems to much advanced in mid Rpm. I try a DA ignition next and let you know here
Michael