ORIGINAL: NM2K
ORIGINAL: s�rpet
My newest fox engine .25 is not good engine it vibrating very badly high revs, leak fuel from front bearing, cant hold needle settings, itry many different fuels, synt, castor, low nitro, no nitro, high nitro.
Os .25fx is 100% better engine.
New engines shake more than engines that have been ran for a while. Balance your prop and run the right size (9x4 to a 10x4).
All glow two-stroke engines must leak some fuel from the front bearing, otherwise the crankshaft would seize. Yes, it can be a bit sloppy, especially if your engine has a bushing instead of a ball bearing supporting the crankshaft.
New Engines aren't broken-in, as we say in America. Once enough rich running time has been accumulated, the engine will loosen up and cool down a bit from previously runs. Cooling down means that the engine isn't as tight as it was before - which is good. Hot engines do not hold needle settings well, which is why it is best to run a few tanks through the engine on the bench.
Fox engines need A LOT of the fuel's oil to be of the castor oil kind. Your engine will run much better and will last a lot longer if you run 20 to 25% castor total oil. Follow the instructions and you will have a great engine. Your Fox .25, if it is the ball bearing version, will eat the OS .25FX alive once it is broken-in and the right fuel is being used. Sorry, but that is the truth.
Ed Cregger
bull****.
best what ballbearing fox can make was apc 9x4 15030rpm and jxf 9x5 13800-14100rpm
1.5l fuel used breaking in engine and 15 flight.
iuse engines 1:12 aces combat planes
my best os fx engine run with apc 9x4 almost 16000rpm and jxf 9x5 14600rpm and they are very smooth.