Back into MA Tempest FAI

[matt jenner]

After some time I have gone back to a Tempest FAI.

I lost a tempest 3d last year after a short that caused it to go in full chat.. I sold it on as spares and went for a Trex 700, although the trex was cheap to replace it just did not have quality feel that my xcell had.

I have got one with a gear Ratio of 8.36/8.43 using an OS 90SZ, so I presume that is a 93tooth main gear with an 11tooth pinion, is there anything wrong with using the same engine and going back to stock gear ratio 7.75 ? What made people change to 8.45 ?

I also am looking for spares, I see the MA Germany is still building up stocks as I have emailed them a few times, I found a couple of places in Europe that have a few spares so am gradually building up a stock pile.

I currently have a Stratus with a OS91 and 4 boxes of spares, it flies really well but I still prefer the Tempest..

Are the parts between a Stratus and Tempest interchangeable ? I guess the head is main difference, but all other parts, are they similar ?

Many thanks

Matt

[trillian]

I don't know about the MA helis specifically but in general the difference between gear ratios of 8.36 vs something like 7.75 depends on what blades you want to run and what headspeeds. With 8.36 you can't get much more than about 1850 headspeed max, which might be fine depending on your flying style. With 7.75 you could run 690s and get over 1900 headspeed. Max power on that engine is at 15000 rpm. If you want to run heavy 710s like the Radix F3C blades then I think that engine would struggle a bit at 7.75 gear ratio. It might have enough grunt on high nitro, I have always run mine on 15% (Robbe Dyna-X).