Instead of a Pinion, Use a clutch bell? and double check my gearing please.
 

Hi Everyone!

Firstly... Thanks to simplechamp for delivering me this awesome ofna centre diff!

I am quite shocked by how amazing the build quality is!

Question 1
Anyway, as i decided against the slipperential and because i am converting my savage flux to a CD rather than a tranny which has a slipper... I feel i may need some sort of give in the drive line....

I saw somewhere but i cant remember, someone using a clutch bell and pads to protect the motor. Basically a nitro setup...
Is this easy enough to do? Would it be possible for my 1520? And is it necessary taking into considering the weight etc of my ext savage?

Question 2
I just want you guys to check that my gearing is correct before i buy the wrong pinions. I am just a little confused as it looks ill be using 9t-11t pinion to get my desired speeds... Smaller than i have ever used (never had a centrediff)

http://i878.photobucket.com/albums/a...earingcd6s.jpg

Does this look correct? These are the speeds that i am running now with my current 18/47 gearing, and with no heating issues etc... so i am looking to maintain these speeds with the centre diff....

Thank you

1.- Tekno RC makes a clutch adapter to use standard clutches on electric motors. This would give you an area for stress relief, but also adds maintainence to your vehicle because of worn out clutch shoes and bearings. Another factor to consider is that the clutch systemadds the width of the clutchbell to the overall length of your motor/gear combo.

It is a viable option, but not one I would choose.

2.- That gearing is correct. A transmission offers the gear reduction you need for a good spur/pinion combo, but adds a weakpoint. A CD eliminates the weak point, but doesn't have the gear reduction necessary for an ideal spur/pinion combo. But it will work!!

Thank you for the fast response...

1. How strong are these motors are taking abuse? i have basically been running my savage with the slipper tightened all the way so far... Should the motor be fine? As long as i dont land and big jumps on power then nothing should really go wrong correct??? I dont mind my weak point being my pinion as it is easy enough to change, i just dont want to be replacing my f/r diffs and CD spur.

2. i guess having a very small pinion means it will wear very fast... at least that will wear and hopefully wont wear out my spur too quickly...

I was looking at the Novak Pinions, hopefully they should be all gd

The motors are quite strong and take abuse well. Not landing on throttle (driving sensibly) will keep your motor running for a long time. Have fun!

thats all i needed to hear. Thanks a lot!

Pictures and info!!

on what??? my conversion??? once i start installing everything, pics will be taken and posted in my thread.

On the ofna center diff that simplechamp did for you!

will get pics up tonight.

I don't know if you can use a CB with Mikes CD mount. The adapter plus CB will extend the gear face out quite a bit. You maybe able to reverse the CD so that the spur is opposite of the motor, but IDK.

Tekno always used set back motor mount to acct for the length

Harold always used rubber donut sex spacers to acct for the length

I fixed that for ya, Finn.

When Fisting or...? Haha

Tip: Always use spellcheck....

It's nothing I did to customize it, I just sold him an Ofna 8-spyder diff.

I am spellcheck. Always re-read what you typed!

Well you've gotten modest. Linc said you always liked the full length colonoscopy

Hello,
Just to say that clutch bell setup will increase the distance between front bearing and mesh contact, resulting in a lot of stress on the front bearing !!! And that is BAD for efficiency and bearing ;) Forget it... Contact some pinions suppliers and buy them by quantity of 20 :lol::lol:

oh yea... didnt look at it like that...

My CD Diff setup is under way... Changing pinions and setting mesh will be easy with my new setup, so i am not so worried now

Not true nuz69. IT has not been bad for efficiency in our years of testing the clutches in our many brushless racing vehicles (truggies included). Our bearings last many times longer compared to a nitro clutch and this is with standard cheapo bearings. There are way more issues involved with running a pinion directly connected to the drivetrane with no disconnect like a slipper or a clutch. A pinion directly relays all of the initial torque of motor start up and under braking the issue is compounded. This relay of torque is moving out to the driveline components like outdrive cups and CVD joints. This is where the problem really exists, not in a clutch bell bearing.

Yes but mechanically the force on the front bearing increases with the distance of the mesh, that's why for example the RC elite motor mount include another bearing to dispatch the stress between front motor bearing and the mount bearing...
Maybe your bearings would have lasted even longer without clutch bell... Anyway like you say the best solution would be pinion + slipper, but most of people run their buggies and truggies with a direct drive system without drive train problems...
For the Monster-trucks an the other hand, with their very high grip and large tires, the drive train is more stressed for sure so a slipperential could be needed...

Yes it does, but that's like saying "don't run a pinion, because it hangs off a shaft that has a bearing supporting it too far away". At some point, the design is given faith that it will work. The clutch "works" and doesn't blow out bearings, doesn't make mesh issues, doesn't hurt anything, in fact we are very surprised to see how little we have to maintain them in order for them to keep working perfectly.

Point is, we both choose different ways to run our motors in this hobby and I am trying not to mis-lead anyone that may want to choose a very accepted option (the clutch) by giving them all the information and not just one point of view.