Rotomotor 85FS, 85cc four stroke opposed twin cylinder gasoline engine with electronic ignition
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Rotomotor 85FS, 85cc four stroke opposed twin cylinder gasoline engine with electronic ignition

Out of Stock
 
$1725.00
 
Item# (ROTO85FS)

 

  • Overview

Now is the time to take advantage of our great intro pricing!

Troy Built Models has selected the Rotomotor 85FS opposed twin cylinder four stroke engine to introduce customers to the Rotomotor experience.
We feel very confident you will agree this is the finest opposed twin cylinder four stroke gasoline model aircraft engine available.

The goal for the new 85FS four stroke engine was simple.
It must be easy to start, develop very good power, be fuel efficient, operate quietly and be extremely reliable.
Well, they succeeded!
An extraordinary amount of technology is packed into this gem of an engine.
It truly belies its simple lines and clean exterior!

The Roto 85 FS is very powerful. It will swing a 26x10 two blade prop at 5800rpm generating approximately 45lbs of thrust.**
It really is the perfect choice for 1/3 scale aircraft such as Piper Cubs and 30-33% aerobatic applications.
The Roto 85 FS provides extreme fuel economy with very quiet operation and makes it a "no brainer" solution to its thirsty and noisy two stroke cousins.

The supplied standard headers will offer minimal noise levels by themselves, but if you really want to quiet the engine down we recommend using the optional FS mufflers.
We recommend thoroughly reading the manual as supplied under the "Manuals" tab. If you have any further questions please do not hesitate to give us a call.

This is a very exciting introduction to our engine lineup!
Act now to take advantage of our special introductory pricing!

**a proper and adequate break in is required

Our intial order of Rotomotor FS engines has been received and shipped and so far the response has been exceptional.
TBM is now the official Rotomotor distributor within the USA.
TBM will be the Service and Support center for Rotomotor FS engines and will honor all factory warranties for Rotomotor engines purchased through TBM.


Rotomotor 85FS Exploded Parts Diagram
Item no. Description Qty.
8501 Engine block 85 left 1
8502 Engine block 85 right 1
8504 Bearing 61800 2
8505 Cam spacer 1
8507 Cam 1
8508 Cam gear 1
8509 Cam rim 1
8510 Timing gear 1
8511 Crankshaft 1
8514 Hub 1
8515 Bearing 6002 1
8516 Cylinder 2
8518 Cylinder head 2
8519 Back engine cover 1
8520 Tube of tappet 4
8521 Propeller center bolt 1
8522 Propeller mount. Plate 1
8523 Tube of suction 1
8524 Tube of exhaust 2
8525 Lever cover 2
8527 Cylinder bolt 8
8528 Nut M5 8
8530 Nut of carburetor 2
8532 Carburetor 1
8533 Air intake 1
8534 Spark plug NGK M10x1 2
8535 Imbus M4x35 6
8536 Imbus M4x10 8
8537 Set of screws of en. Block 8
8539 Carburetor bolt 2
8540 Screw of lever cover 2
8541 Piston 2
8542 Connecting rod 2
8543 Bearing HK 1210 2
8544 Bearing HK 1210 2
8545 Wrist pin 2
8546 Piston ring 2
8547 Valve guide 4
8548 Suction valve 4
8549 Seat of valve exhaust 4
8550 Rock lever 4
8551 Rocker-pin 2
8552 Snap ring of wrist pin 4
8553 Lock washer 4
8554 Spring rest 4
8555 Tappet 4
8556 Stick of tappet 4
8558 Screw of tappet 4
8559 Nut M3 4
8560 Screw M2,5x5 2
8561 Bearing 6003 1
8562 Valve spring 4
8563 Seat of valve suction 2
8564 Exhaust valve 2
Displacement 85 ccm
Power 5,5 PS @ 6000 rpm
Bore 39,5 mm
Weight 2 790 g / 6.14lb
Piston Rod 4 × NEEDLE BEARING
Crankshaft 3x BALL BEARING NSK
Ignition Processor Roto - Do not exceed 6v! *Battery Information
Fuel GAS + OIL MOTUL 710 1:40
Fuel Consumption 2l/hr @ 5500 rpm
Propellers 2-Blade: 26x10
3-Blade: 23" - 24"
For scale sound/operation (low rpm): 2-Blade 27x8 or 27x10 max

Dimensions
ROTO85FS.pdf

TBM will be the service support center for Rotomotor engines.  
Rotomotor warranty is 40 months.
We will supply warranty support through Rotomotor with their approval pending pics of failures and serial #'s as we do now for other engines.
For any warranty issues, the customer pays for shipping to TBM and would not incur any further costs for warranty related services or shipping back to them.


 
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Allied countries of the United States regarding shipment of any products from TBM

WARNING - Gasoline and Turbine powered R/C model aircraft are not manufactured to withstand unlimited G's. Any R/C model aircraft can fail, be it a wing folding up or a fuselage breaking in half under too high of a load. Just as any full size aircraft, model R/C aircraft have a maximum G rating. Because you are not in the plane flying it and experiencing the G's and reading the G-meter, it is more difficult to judge the G's on the aircraft, and it is very easy to exceed the limits of the aircraft. Understand that if you perform a snap roll, parachute, wall, blender, knife edge loop, or pull hard on the elevator at almost any speed, you can be putting in excess of 15 G's, even in excess of 30 G's, and most aircraft can only designed to take 10-12 G's. If you perform any violent maneuver, you can break your plane. When I perform hard maneuvers, especially for the first time on an airframe, I am prepared for a failure and am prepared for it as best I can be. This mainly includes performing the maneuver far enough away from spectators that in event of a failure that I am not endangering others. In addition, be prepared for the manufacturer to not pay for a new airframe which is broken during flight. It is common practice for any manufacturer to not replace an airframe which breaks in the air or upon landing. I have only seen manufacturers replace airframes when they have received many of the same failures and the manufacturer determines that there was a design or manufacturing error. If you break an airframe, and you are the only one to do so, then it is probably not the fault of the manufacturer. Please fly safely, and avoid full throttle operation other than at low airspeeds.

R/C model jets, warbirds, aerobatic planes and UAV Unmanned Aerial Vehicles to name a few are not a toy! If misused, it can cause serious bodily harm and property damage. Fly only in open areas, and AMA (Academy of Model Aeronautics) approved flying sites. Follow all manufacturer instructions included with your plane, radio, servo's, batteries and engine. Aircraft manufacturers guarantees each kit to be free from defects in both material and workmanship at the date of purchase. This warranty does not cover any component assembled by the customer. All parts of high stress must be inspected and reinforced if necessary by a competent builder. Some parts should be glued again. High stress areas such as firewalls, motor boxes, wing mounts, landing gear mounts, etc., are areas of high concern. Seek help if necessary. In not case shall TBM be liable for the cost of any product it offers which is not manufactured by TBM. The liability to the manufacturer cannot exceed the original cost of the purchased item. Further, TBM reserves the right to change or modify this warranty without notice. In that TBM has no control over the final assembly or materials used for final assembly, no liability shall be assumed nor accepted for any damage resulting from the use by the user of the final user-assembled product. By the act of using the user assembled product, the user accepts all resulting liability. The kit manufacturers have provided you with a top quality, thoroughly tested kit and instructions, but ultimately the quality and fly ability of your finished model depends on how you build it; therefore, we cannot in any way guarantee the performance of your completed model, and no representations are expressed or implied as to the performance or safety of your completed model. It is the user's responsibility to inspect each component for worthiness.