New YS 120SRX

[Leon Luke]

NEW 120 SRX I have been testing a new motor that has performed flawlessly. The testing is done and the motor is ready to be released now.
1) The motor has a new crank shaft with new balancing needed to make the 120 smoother, this should not be a complaint anymore.
2) The crank case is different inside and out. Inside, porting changes made for more power and smoother running. Outside, the case has been modified to accept new head sink head to extend down lower.
3) The head/heat sink is much larger and extends down much lower towards the crank. The head fits around the cylinder case like a jacket, as the cooling fins have been machined away.

I've been running Cool Power 20% on 8:1 with headspeeds 1950-2000. Motor runs very happy and is very easy to wide tuning range. For those that run electrics, the 1950 headspeed may seem low, but the torque of the 120 and lower weight of the nitro helis in general make it a machine that flies effortlessly. You can tic toc for minutes on end and it just keeps powering through with no sag and no leaning out.

I've been running the tareq 91 as my preferred motor due to tunability and power approaching the 120, but now I'm going 120!

Please contact the YS Facebook page for more info on availability. I believe this is a limited production run for now.

The YS SRX 120 motor is coming out and going into the Mostro. I'm thinking it's gonna run even stronger in the Mostro with its better cooling system.

[Bob O]

The increased cooling ability of the head is a great feature! Can't wait to see it in the Mostro.

[Jim Hansen]

Sounds good Leon. Thank you for the update. Is there a release date?
Thanks again.

Jim Hansen

[Leon Luke]

Very soon! You can check YS Engines on FB.

[Matt Nasca]

I'm excited to see the new 120 with all the improvements! The 91 SRX Tareq is awesome too so YS looks to have two winners for the .90 market!

[DominicD]

I don't mean to derail your thread Leon but I do want to ask a question about Nitro engine development. Unless I am crazy it seems we have had a ton of big improvements to engine performance only after electric flight became so overwhelmingly popular. Is there something new to engine designs that has allowed these new designs or were the engine manufactures just complacent in the past ?

[Leon Luke]

In my opinion, nitro engine development is kinda like a black art that requires alot of trial and error and thus money. A lot has to do with the resurgence of interest in nitro as evidenced by some new models from a few manufacturers, that have encouraged the engine makers to invest money into development.

[robertvizzo]

One of our club members (Matt Stringer) got to fly one in a trex 700n this weekend in Bakersfield. He reports it has crazy power running at 1900. I will be getting one as soon as they come out. Matts dad tells me that this motor will be able to turn 2200 on 20%, is that even possible?

[MikeG4936]

What kind of pipe can we expect to run on this motor? Will the old 120SR pipes work well, or will Hatori and Funtec be producing new pipes for the SRX?

[Leon Luke]

I used the Hatori YS 120 pipe and it works good. I don't know of any special pipe from Hatori for it.
As far as 2200 HS is concerned, it all depends on your gearing. I never ran it higher than 2000 HS on 8:1.

[Sky_]

Please post a VIDEO.

[jwatts007]

I am looking forward too getting one of these beauties...hopefully I will not have too wait too long...I have had no end of fun with my 120 sr engines and these should be even better....

[Matt Nasca]

Here it is in all its splendor!

YS120SRX HELI

• New crankcase design for increased power and efficiency.
• New oversized cylinder head for more efficient heat dissipation
• New balanced crankshaft for smoother operation
• Steel lined back plate to decrease drag for more power

Specifications

• Displacement: 19.93 cc
• Bore: 30.38 mm
• Stroke: 27.5 mm
• Practical RPM: 2,000 – 16,500
• Weight: 582 g

[Sky_]

Damn!

I need a YS120SRX immediately!

[MikeG4936]

What nitro % works best with this motor?

[Matt Nasca]

15% - 20%

[Leon Luke]

I put in some more flights yesterday and it still impresses. This is my number one choice over the previous favorite of Tareq 91!

[Sky_]

Originally Posted by Matt Nasca

15% - 20%

Oh no - i have 20 Gallons of Rapicon 30%.

[dodgeboy]

Originally Posted by Leon Luke

I put in some more flights yesterday and it still impresses. This is my number one choice over the previous favorite of Tareq 91!

Really??? Cause the 91srx is bad ass. What area does it show its better?
The 91srx was a ton better than my os105 hzr for low end tq. It is able to hold the rpm better throughout the entire flight. Tuning was slightly different than my 105 but I feel I got a good tune on my 91 now.
You know when I first bought my first bigger nitro motor I went with the os105 cause I thought bigger is better. Now that I have the ys91srx I know thats not the case. I have always stayed away from the ys120 due to other have stated it was a jack hammer. I have seen people say they would have to change their booms due to the vides the 120 produced cause it would start to crack the boom at the boom blocks. How are the vibes with this motor compared to the older version???

[Leon Luke]

Originally Posted by dodgeboy

Really??? Cause the 91srx is bad ass. What area does it show its better?
The 91srx was a ton better than my os105 hzr for low end tq. It is able to hold the rpm better throughout the entire flight. Tuning was slightly different than my 105 but I feel I got a good tune on my 91 now.
You know when I first bought my first bigger nitro motor I went with the os105 cause I thought bigger is better. Now that I have the ys91srx I know thats not the case. I have always stayed away from the ys120 due to other have stated it was a jack hammer. I have seen people say they would have to change their booms due to the vides the 120 produced cause it would start to crack the boom at the boom blocks. How are the vibes with this motor compared to the older version???

I like you loved the 91 Tareq, as mentioned earlier, I preferred it over the previous 120. And have always said it had more torque than the 105.

But with the 120SRX the game has changed.

The 120SRX is smoother now due to a different heavily balanced crank. It is on par with the 91 Tareq in that regard.
The 120SRX is very easy to tune with a very wide window, that is not very critical. It is on par with the 91 Tareq in that regard.
The 120SRX has without a doubt, greater low end torque than the 91 Tareq.

At 13.5-14 degrees full collective with the tareq you can hear it reaching its limits, and with the 120SRX you do not, it just keeps going and smoke is consistent.

In hard tic tocs like 20 in succession, you can begin to see the tareq warmup and lose a bit of smoke, the 120SRX keeps running consistently.