Daniel Z

I have a Ys 110 working with good idle and transition but giving me about 8700 rpms with a 15x8apc, using new ring, so I`m a little disapointed
Changed the valve cover gasket and improved to 9100 rpms , I still think It can be better , all the rest af the engine is very well mantainned

any ideas?

Daniel

Zeeb

My Feedback: (41)

Umm....

That's not all that far off what it should be. What percentage nitro fuel are you using? I've got a couple of these little beasties and can get about 9500 max static RPM on an APC 16x6, so if you accept that going down an inch in diameter and up one step on pitch is roughly equivalent, you're pretty close but the nitro percentage will have some bearing on what it'll turn. Have you checked the valve clearances? That'll make a difference as well if those are off, usually too loose.

Zeeb

My Feedback: (41)

double post.

petec

My Feedback: (58)

It would help to know what fuel you are using. Your numbers are in the ballpark.

wcmorrison

My Feedback: (2)

Check your regulator diaphragm.  I had trouble with a 63 that would not get over 8,600 RPM.  Idled well, etc.  Changed the regulator diaphragm and it zipped right up to 10,500 ~ 11,000 RPM.  Been a go'er ever since the change.  Be careful not to lose the little parts when you open up the regulator.

Chip

ThumbSkull

My Feedback: (57)

With 30% and a 16x6 Xoar, I get around 9200 peak. That's a lot of prop so I'm not sure why you are disappointed.
16x6 and 15x8 are very similar power factor so your engine seems to be about right.
Are the results not enough in the air? What bird are you motivating?

Daniel Z

I`m using wildcat 20/20, the regulator diafragm seems a little distended but at 4k is ok and transition is good, I will try a new one anyway (thanks wcmorrison)
I`m flying a 3,5kg or 7,7lbs plane (Aerokevlar Panther) and I want more power for vertical lines, and pulling out of torque rolls

Seen posts of people with ys110`s puting 10k+ on a 16x4 or 15x8 is not unususal and is 20% more than mine!

I will change orings too, Any ideas will be well recieved.

Thanks for your help

ThumbSkull

My Feedback: (57)

You would probably see 10K+ with a 16x4. It's not as much load as a 16x6 or 15x8.
I'd bet the guys saying they get 10K+ are using a 15x6 and not a 15x8.

For your 7.7lb plane, I'd certainly try a 16x6 Xoar, JXF or APC sport. Those should get you the best static thrust and reasonable top speed.
They will also slow your down-line speeds. Not all mfg's props are equal.

bigal126

My Feedback: (18)

Hi,
I have a related question. I own the 110 fz. I use the 16 x 6 xoar and it works great. Flies the plane fine for my style of flying. However, I took the engine out of my 9.1 pound CG extra and put it in an 7.8 lb bird. For a replacement I got the 110FZS version. Does it take the same prop, or should I use something bigger? Thanks.

ThumbSkull

My Feedback: (57)

FZ and FZs are same power just different pump location.

tande

My Feedback: (48)

With all due respect...The FZs uses a "Sealed crankcase" & the FZ does not...."WHEN" [&o] you can get the FZs adjusted correctly it will pull another pitch# higher than the FZ...Again FWIW... My experience...YMMV...

Zeeb

My Feedback: (41)

Well my FZ engines will pull over 10k on an APC 16x4W prop, just not enough prop and when it hit the mid 10k range I shut it down and never did try to peak it with that prop. As I said they run in the 9500 RPM range on an APC 16x6 and I richen 'em up to about 9200 RPM for flying initially then see what happens on the uplines and adjust accordingly. I didn't mention it before, but that's with CoolPower 30% heli fuel and although field elevation doesn't affect the YS engines as much, I'm at 4500' ASL here in Utah.

Daniel Z

Well , then I`m missing about 500 RPMs not 1000 as I thought, do you agree?

I have a 16x4w and a 16x7 apc props , will replace the orings, change props, and tach the engine again

I have a MAS 16x6 , Does it worth?

still4given

Check the fit on the rear disc. It should be very close to the the back plate. Also, RPM readings vary greatly from place to place. Did you get more RPM before you changed the ring?

Daniel Z

No, I had about the same 8700 rpms before , that´s why I hoped an improvement with the ring replacement.
Changing the valve cover gasket made it a little better (9000-9200 peak)
I`m just over 500 ASL, have tried 30% while ago but I haven´t noticed changes in performance (dont remember tach readings)

I thought my plane should be on the overpowered side at 7,7lb with this engine that`s why I`m scratching my head

Will watch the rear disc also, thanks still4given

Thanks again for everyone

Zeeb

My Feedback: (41)

Don't forget to check the valve clearance while you're at it....

Also, there can be some differences in tach readings depending on who's tachometer you're using. I finally went to a TNC tach as I was getting different readings from, shall I say, less expensive tachs? Now I'm not pushing that particular point here as my 110's will haul a 9lb. model around with authority so the fact that you're having what you think are performance issues with a lighter model would suggest your tach readings may be close. Just a thought.

I've never tried an MAS prop but from my experience with the GS gasser stuff, props can make a tremendous difference on those models and you pretty much have to try different manufacturer's and sizes to get a suitable prop for your particular flying style and a particular model/engine combination. Also, going from 20% nitro to 30% yielded more RPM and a slower idle with the engines being a bit easier to tune when I did the fuel change. You should, I think anyway, be able to notice a difference between the two different fuel nitro levels.

petec

My Feedback: (58)

Let me step in here.

You can see a difference between tachs, I lost RPM when I got a new tach when my old tach from the same manufacturer met it's demise. RPM should be a ball park and not an absolute.

Pros make a HUGE difference. An APC is going to retain it's shape at higher RPM and air load than some other thinner props and that will also give you a lower reading for the same diameter and pitch from manufacturer to manufacturer.

Higher nitro content will give you a higher top RPM by a few hundred RPM depending on nitro content. Higher nitro will also give you a broader sweet spot on the needle at the top end and bottom end.

As for the FZ vs. FZs, the FZs made slightly more power but functionally they are the same.

Your RPM readings in your first post are in the ball park and certainly valid for 20% nitro. For comparison I would swing a 15x10 APC at 8800 RPM on 20/20 on the nose of a 1.20FZ.

Daniel Z

Ok, today I bench tested the engine again, with the new Orings and gaskets (and ring)

20% wildcat fuel

15x8 @ 9100-8800 (not stable)
16x4w @ 9900-9600

The only thing not looking good is the diaphragm, its not flat, a little bulged, anyway I can have decent transition
Is this thing enough to steal my missing RPMs?, I know Chip said it does, but I want to know everyone experience

Thanks,

Daniel

petec

My Feedback: (58)

8800-9100 RPM on 20% with a 15x8 is respectable RPM. I'm curious what you mean by not stable though.

The regulator diaphram will stretch a little but if its bulged the next step is torn, replace it.