Modification to brand new Hyper 50 motor????

[stevejr72]

Just bought a Hyper 50 motor for my Raptor.
Speaking with the owner of another LHS, he told me that if I wanted my motor to last more than 1 gallon of fuel, I need to dremel something out of my motor... :dontknow :dontknow :dontknow

Sounds almost like he wants me to ruin it before I even get to use it.

Has anyone here ever heard of doing this?

[Mike C]

I've heard of some balance issues with people removing the web from the crank.

Some will swear by it.

No way I would do it. I've not had any problems with my hyper (that I didn't cause).

If a bearing makes noise change it ,,I havn't had to yet :dontknow

[stevejr72]

web?
Why would removing it help? I thought the OS Hyper was top notch... Doesn't seem to make sense to me why OS would make such a great motor with a problem that requires a mod like that.

[Mike C]

It doesn't, but every time a fan comes loose, and trashes a rear cover and shoots trash through the motor people blame the rear bearing. That along with the real failures that happen now and then. And then throw in a bunch of modeler with nothing better to do ,,there you have it. Pass it around the internet and then it's a must have.

Search Crank web mod. I'm sure you'll find it here. In one of the recent MHT issues , the auther (Ashley Lightfoot) wrote about doing the mod. then started loosing servos due to viberation. He thought he was smarter then the OS engineers :dontknow

[stevejr72]

Can't find the thread... really interested in seeing it.
A little help please.

[Motions]

Most people I know have done the web mod including me. It doesn't provide any more power but it reduces vibration quite a bit. It's not a hack job, you need to know what your doing.

[stevejr72]

Motions,
I still don't get it though... Why would OS continue to make this motor if it requires such a mod in order to run properly?

[Motions]

It does run properly as designed. OS designed the crank web to cover the rear bearing. I'm not sure why it was designed that way. By removing this web, it doesn't effect performance but it does balance the crank a little better and reduces vibration. It's not really needed but it runs much smoother.

[BarracudaHockey]

I definately would NOT do it until the engine is out of warranty though.

[Motions]

BTW, you have one now Andy. :smokin:

[flyinfool]

It is all just smoke and mirrors.
While at the last place I worked at I tried removing the web and then tested using some very expensive vibration test equipment.
I had accelerometers mounted in the X, Y and Z directions with X being perpendicular to the crankshaft and cylinder (side to side in the heli), Y being parallel to the cylinder ( front to back in the heli) and Z being parallel to the crank (vertical in the heli).
I then ran the engine at a fast idle ( there was no safe way to hover the heli with the test gear attached).
All that the crank mod did was to reduce the vibration in the Y direction and increase it in the X direction. The total amplitude of the vibration did not change, only its direction.
As one would expect there was very little vibration in the Z direction, and it did not change with the mod.

It is not possible to balance a single cylinder engine like what we are using. You can choose which plane the major component of vibration occurs by changing the weighting of the crank.

[BarracudaHockey]

Dang I wish I had cool toys like that!

[flyinfool]

I wish I still did. :arggg:

[Scamp62]

check out the mod here:
http://www.runryder.com/helicopter/t243245p1/?highlight=web+mod

[Motions]

It is not possible to balance a single cylinder engine like what we are using.
That is absolutely correct.

It is all just smoke and mirrors.
There was definitely smoke but no mirrors. :mrgreen:

[Mike C]

See those that swear by it and those that don't :wink: Mine has been running bout 30 gal. no problem, its been a good engine :lol: No mod needed :wink:

[HeliSat]

I used to race nitro onroad. There were a few guys that swore by dremel grinding cranks and other mods. There were also the sheep that followed. But at the end most of these guys didn't win races. I did very well with my unmodified engines.

I concluded that these guys were looking for easy solutions to win races, instead of spending the time practicing. :arggg:

I have just bought an OS50 hyper - I wont be doing the mod.