Help me choose an engine

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Hardcore RCTalk User
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Charlotte, NC
RC Driving Style
  1. Bashing
  2. Racing
I have posted that I was planning a .21 conversion. I started thinking if I am getting myself into trouble. Will I be replacing dif and tranny gears after every run? I'm worried about reliability.

I've seen lots of posts from happy Fantom .15 owners. I'm interested in checking out what the hype is about.

I cannot ignore the quality and reliability of OS motors. I'm looking at the .15 CV-X.

I want to be able to do the following:
1) Run off-road with decent speeds
2) Have enough ponies for some occasional jumping
3) Be able to do wheelies for showing off

I'm currently runing 18/72 gearing.

So what do 'yall think? Drop a .15 in or go for the .21 conversion?
either the os .15 cvrx,or the fantom.the only difference is one has bottom end and one has top end,just depends on what you think about the probs some people have with fitting the fantom in.
the os is cut the crank and drop it in.
I have the OS CVX 15, it is a bad a$$ engine. Plenty of power for offroad and jumping and yes wheelies. I am also running 18/72 gearing. I have not tried a cvrx yet but that will be my next engine. You also have to look at cost, how much you want to spend will also make a difference. You will want to upgrade the plastic drive shafts, after only 7 tanks my OS was twisting them, so I just put a full set od Dynamite cvds to handle the new power.
Well I just heard that OS is coming out or has come out with an OS CVRX 15 SHORT SHAFT, no mods needed just drop it in no cutting. :banana: Thats my next mill.
Is the New OS your referring to Just for the Maxx?
The OS CVR-X (s) Short shaft is what I have in my Maxx and yes the shaft it shorter but still needs to be cut .
No I dont think so, I have just found out about this short shaft OS cvrx but I was under the impression it did not have to be cut. :confused: Thats ok though I had to cut my OS shaft and it is no big deal, its still gonna be my next engine. So what do you think of it FastEddy?
I have no problems cutting the shaft since I have a dremel.

As it looks so far I should try out a .15 first.
I am leaning towards the Fantom right now. :)

I'm not worried about drive shafts because I've upgraded to Dynamites already in anticipation of an engine upgrade. :banana:
you will not need to change the shafts with the fantom;)
I have both the Fantom and the CVR-X I love both of them. If I bash or race on a short track I use the OS if I race on a large track I use the Fantom.

The AE GT comes with a shaft-cutting tool that works great with the OS or Fantom.
You just screw it onto the shaft and cut even with the end. Wa-La a perfect cut. I will try to find the part #.
you seem to be the first guy from the USA to say low end is cvrx,and top end is fantom,which is what i find myself.
get the os and be a happy maxxer,or get the fantom:)
I still dont think thats right.
I got the (S) and needed to cut.
Did they change the specs?
Oops Sorry..
I got the .12 (S) for my XXX.
I had to go look at the box.
*****Sorry for the Mis-Info******
Easy, I have an OS CVX .15 right now, but I want the CVRX. I am very happy with it but I am always looking for more power. My Mutant head should be here today or tomorrow, I hope. I can't wait to get that thing on my OS :banana:
while i am this happy with os i would not get a mill made by anyone else,i find that they are suited to my needs and likes.
more power is always nice too.