Since 1986, O.S. owners have enjoyed the unique experience of owning and operating the fabulous FR5-300 Sirius 5 cylinder radial. Models have become bigger over the years and O.S. wanted to release a new radial engine to cater for that market. The result is the gorgeous FR7-420. With 7 cylinders and a capacity increase to nearly 70cc, the FR7-420 offers a dramatic increase in both torque and power. In keeping with the scale image set by the Sirius, the new FR7-420 has been styled in the same way with front pushrods and separate rocker boxes for the inlet and exhaust valves. These totally new cylinder heads are not just about 'style', they offer a more efficient design that contributes to the power output. That neat frontal appearance is maintained by keeping the single, dual needle carburettor at the back and hidden in the centre of the engine mount. The prototype engine shown here will have some detail changes (cast cylinder heads etc) made before release, but the general style will be similar. It would almost be a crime to hide it away in a cowling!
Quality and style this good is something to be proud of owning. The wide range of large propellers recommended makes choosing the right one for your model simple. At these sizes, they could be close to scale!
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Refund Policy
You have the right to cancel within 7 working days after the day you take receipt of goods. You must notify us within this time that you wish to cancel. You are required to take good care of the goods and return them to us at your own cost within 30 days. Your product must be complete, unused and in ‘as new’ condition (e.g. if you have opened the box to examine the product you must have done so without damaging or marking the product in any way). It should be returned with the original box, packing and accessories. If the returned item is in a condition which does not enable us to resell as new, we reserve the right to make a charge from any refund to cover this cost. We recommend that goods are returned by recorded or insured delivery. If you would like to phone our despatch department we can arrange to have the item(s) picked up. We will subtract the return cost from your refund. No refund will be provided for lost goods being returned to us, as this is the responsibility of the sender. We cannot cancel your purchase when: • The seal is broken on any software in the case of a simulator. Special Orders - If the goods were a special order that we do not have in stock and have had to order specially - If you cancel we reserve the right to charge a restocking fee of 10%. If we send a substitute without first checking that the substitute is acceptable then consumers are not expected to pay return carriage costs. These rights are in addition to those relating to faulty or misdescribed goods. If goods are returned as faulty, generally we will provide a replacement. If the item is of a ‘ready to go’ type model eg. Helicopter, plane, car etc. the item will be sent back to the supplier for a decision to be made in respect of a refund or replacement. Only then will a decision be made