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need opinions/advice on clocking my axles..Shorten my links?

kushboss

Newbie
Joined
May 26, 2019
Messages
29
Location
canada
i have been doing a lot of searching on here and i cant seem to find a thread that is the same as my situation the question i have is judging by the photos do you think that my rear axle should be clocked up towards the truck my is the front one alright? i personally think my drive shaft angles are acceptable but i want opinions on it part of the reason im wanting to clock the rear is because the pumpkin is in a position that it is the part of the truck that hits rocks most frequently also the shocks on my wraith are just temporary just saying that before someone roasts me for it that being said shock recommendations for a 8 pound wraith are welcome i am wondering if i got shorter rod ends like the revo ones and installed them on the upper arms if that would pull the axle in enough? any help is greatly appreciated
 
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You managed to never take a side on pic which is what would show pinion angle the best lol

You appear to already have Revo rod ends.
Shorter rod ends on the upper links would only tip the pinion down more, making it worse.
Jato are the longer ends but from my experience looking at your set-up they would be too long & would tip the pinion up far to high.

I run mine, be that crawlers or fast U4 trucks, with the pinion pointed near as I can, at or just a whisker lower than the out put of the trans.
Yours appears about the same.

ps- punctuation in your post would make it much much easier to read & identify the question, that long continuous string of words is difficult to follow.
 
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I really cant tell what your pinion angle is from the pictures, they're all too close up. Get a shot from the side showing the table and the pinion from a distance (with a tire removed).

Or you can judge for yourself, an ideal pinion angle would be parallel with the ground (though with RC you can point the pinion up a bit without too many issues).

If you need to adjust the pinion angle adjust the link lengths just like you mentioned, you could adjust both the uppers and lowers to keep the wheelbase the same or just adjust one set if you dont mind deviating from your wheelbase. You dont necessarily need new rod ends, I often trim a bit off the ends to get the length I want, just make sure you've got enough thread grab afterwards if you do this.
 
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I really cant tell what your pinion angle is from the pictures, they're all too close up. Get a shot from the side showing the table and the pinion from a distance (with a tire removed).

Or you can judge for yourself, an ideal pinion angle would be parallel with the ground (though with RC you can point the pinion up a bit without too many issues).

If you need to adjust the pinion angle adjust the link lengths just like you mentioned, you could adjust both the uppers and lowers to keep the wheelbase the same or just adjust one set if you dont mind deviating from your wheelbase. You dont necessarily need new rod ends, I often trim a bit off the ends to get the length I want, just make sure you've got enough thread grab afterwards if you do this.




By what rationale do you determine that "parallel to the ground" is the right pinion angle?
Parallel to the trans output shaft maybe, but to the ground has SFA to do with anything.
Even parallel to the output shaft would only be critical if the 2 shafts never moved relative to each other, in some kind of completely stationary machine drive & that's 1 to negate high speed vibration & 2 to force the inner joints to actually rotate & even out their wear.



In an rc vehicle, particularly a slower moving crawler, with an almost constantly moving suspension that doesn't even necessarily maintain pinion angle through it's cycle, setting the pinion angle level to the ground is utterly useless.
Tipping it up some towards the trans such that the joint doesn't keep bashing into rocks is far more useful.
 
pinnion angles are different depending on the style joint you running if running cv stle shafts you want the pinnion pointed to the output shaft if running u joints the pinion should be the same angle as the output shaft atleast i the 1:1 world for rcs it dosent matter at all your not sitting in them with a crawler nothing spins fast enuff to hit the point of resination so it wont affect your bearings you dont ballance the tires do you and they have way more affect o the rig thana slightly out of ballance or out of phase drive shaft if you want more clearance under the pinion go for it or not
 
By what rationale do you determine that "parallel to the ground" is the right pinion angle?
Parallel to the trans output shaft maybe,
You're right I was thinking U joints not CV's.


But just to explain the concept that you almost fleshed out above almost all RC's unless custom have their transfer case shafts parallel with the ground so setting the pinion to match gets you the equal and opposite angle thats considered ideal in the 1:1 world with U joint driveshafts. Though there is definitely a lot more flexibility with these angles in RC.


Google image search shows the many ways you can go about this.



https://www.google.com/search?q=pin...rpnkAhUHvKwKHX2tDoYQ_AUIEigC&biw=2560&bih=944
 
thanks for the advice all get some better pictures uploaded i for sure shit the bed on getting a good view lol
 
On multi-stage compressors running large V12 engines we ensure that the coupling flanges were parallel within 0.002" by shimming the mounts. This gives the best balance and universal longevity. The equivalent of this for our RC cars would be to have the diff pinion shaft parallel to the transfer case output shaft as shown below.

553fc71a335b2cb1373db943e2506d28.gif


The link below explains 1:1 driveshafts and why we align our driveshafts the way we do.

http://www.4xshaft.com/driveline101.html

Sent from my LG-H870DS using Tapatalk
 
I am aware of all the reasons why in 1:1 it's worth aligning driveshafts correctly, especially with fixed plant like a compressor drive or a road going vehicle with drive shaft speeds in the thousands of rpm.

I also say it total bollocks to be worrying about it with rc crawlers, there's more to be gained be not smashing that pumpkin & uni joint into rocks than any tiny imperceptible negating of wear or vibration.
And as I said above, who here is actually tuning their suspension to maintain pinion angle through it's entire travel? My bet is less than 10%
 
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