i bought a formula fastech last year and first run out the flex shaft was slipping like crazy when i tried to get in on plain i think its the collet nut. just in case i bought a new flex shaft as well but i have yet to get a coupler as the stock one seems very poor quality.http://www.offshoreelectrics.com/pro...d=aero-couplerwould this fit on the dynamite .15 and im not sure of the flex shaft size if anyone knows that would be greatly appreciated thanks.

i have 2 fastechs,and they both had the same problem.their collets were overtightened at the factory,and then when you loosen them to lube the shaft,they wont tighten again.i just ordered a couple of proboat replacements and havnt overtightened them,havnt had a problem since.i think the flex diameter is .150.if your heart is set on OSE replacements,give them a shout or look on their forums,they're a great bunch over there,they have helped me out quite a bit.

That one won't work as it's made for electric motors. Steve shows this number as the correct one but it appears to have the incorrect one in the picture. http://www.offshoreelectrics.com/pro...=oct-ocfh5mm15 . The Octura part I'm thinking may be too long to fit in place of the ProBoat collet. Aquacraft has a collet also that could go in there but I'm not too crazy about theirs either.

thanks for the response i decided to just order the stock coupler as it will be simple i just have to make sure i dont over tighten it  now all i need is for the hudson rivers flooding to go down