Newbie Flex question

[monarch]

Going thro a step learning curve at present and some help is needed please.
I have the Bullet Hyperformance lower leg with brushless motor mount and need to know is there an easy way to check the free play in the flex drive which I understand to be 1/16" to 1/8".
If the free play is less than this do I grind the flex or add spacers to either the motor end or dog drive where it enters the main housing.
Thanks in anticipation.

[BHChieftain]

Hi,
Are you talking about the space between the dog drive and the strut? There should be 1-2mm gap there as the flex drive will tighten up and shrink under load-- I usually adjust this by pulling the flex drive out a little from the motor coupler,

If this isn't what you are talking about maybe you can take some pics?

Chief

[monarch]

Hi
Not exactly what I needed, I understand that the flex drive should have 1/16 - 1/8" free play between the motor drive adpaptor and dog drive assm but my question is how do I get this flex free play correct, forgive me but this is all very new to me as RC cars are what Im used to so please bear with me. You mention a gap between dog drive and strut what is this for as I assumed that this drive screwed all the way into strut.
Maybe someone could post and idiot's guide to setting these things up properly.

[T-Man]

He's talking about the Hyperformance 3.5 bullet drive outboard lower.
http://www.offshoreelectrics.com/pro...5-bullet-drive
There is no space between the drive dog and the lower unit drive bushing (what would be the strut in an inboard setup). The stub shaft is fixed in the bushing and cannot move. The bushing the stub shaft rotates in is threaded into the lower unit output. The motor is mounted at a fixed distance at the top of the lower unit. The necessary allowance for the cable changing length is accomplished by the fact the cable has a square on both ends and the square ends are slip fit into both the motor coupling and the stub shaft at either end. There are no set screws or other mechanical means for securing the cable on either end. The cable is driven by the square ends of the flex fitting into the female square motor coupling and stub shaft connections. This way, the cable is free to change length while the motor and stub shaft remain in fixed position since there is extra free depth available on both the motor coupling and stub shaft female square connections.

Monarch, I don't believe you should have to do anything other than bolt your motor onto the mount, slip the flex ends into the motor coupling and shaft connections and have fun.

[monarch]

Hi T-man
When I first got the unit the motor drive end pushed down on the flex when I mounted the motor which means that there was no free play in the flex, is this correct.
Sorry to be a pain but I would like to get this thing fully shorted before using and possibly breaking flex drives.

[T-Man]

Not sure; that may just mean that the fit between the flex and the motor coupling is tight. I just bought one of these units and haven't run it yet. I think a lot depends on where you mount the motor coupling on your motor shaft. I will be mounting mine with the top of the coupler as close to the motor can as possible. You may have to grind your motor shaft back to shorten it a little. This would provide additional clearance if you need it.

I believe I would call Hyperformance Products and ask for advice. I believe I will do the same. If you do talk to them, let me know what they recommend.

[monarch]

Hi
I will have to Email them I live on the other side of the pond, but if you call them please let me know outcome, I will let you know anything I find.

[Greg Schweers]

This is what I do: Put the flex shaft into the drive and make sure it slides into the stub shaft. Take the adabtor for the motor, slide it on to where it almost touches the end bell (tighten set screws). Now, set the motor onto the top of the drive adaptor.

If the motor won't sit flush then the cable is too long; and you'll need to grind a little bit off each end.

If the motor sits flush, then you need to move the adaptor on the motor down a little bit at a time, until the motor starts to come off the drive adaptor.

Once you've figured that out, you can back the adaptor up a little bit, and that will give you the play you need.

If the cable is too long to begin with, you need to grind the cable until the motor is flush with the top of the drive adaptor. Once you have it flush, just grind a little bit more, and you should be okay.

Just remember, if you cut the shaft too short, you can always slide the adaptor down. If anything, the shaft is going to get shorter when you run the boat.

[monarch]

Hi all
Thanks that's exactly the info I needed.

[properchopper]

This is what I do: Put the flex shaft into the drive and make sure it slides into the stub shaft. Take the adabtor for the motor, slide it on to where it almost touches the end bell (tighten set screws). Now, set the motor onto the top of the drive adaptor.

If the motor won't sit flush then the cable is too long; and you'll need to grind a little bit off each end.

If the motor sits flush, then you need to move the adaptor on the motor down a little bit at a time, until the motor starts to come off the drive adaptor.

Once you've figured that out, you can back the adaptor up a little bit, and that will give you the play you need.

If the cable is too long to begin with, you need to grind the cable until the motor is flush with the top of the drive adaptor. Once you have it flush, just grind a little bit more, and you should be okay.

Just remember, if you cut the shaft too short, you can always slide the adaptor down. If anything, the shaft is going to get shorter when you run the boat.

Jeez G, that's exactly how I do it - You spyin' on me or what ?