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Programmers
2007.07.14, 06:25 AM
Hey all, as mentioned in another thread I've been having diff problems. So until I get it sorted, I was thinking of using the stock derlin gear diff. I've noticed that in endurance races they're used a lot, and they're also used quite alot in stock class. Is that right or just my imagination?

Could people tell me the benefits of using a stock diff please? And would it be better to use a stock diff rather than a GPM 1/16 ball diff?

This would be for stock class.

Cheers!

bermbuster
2007.07.14, 06:58 AM
they are inexpensive....
you have no adjustments.....
The stock gears can work well if you have very good throttle control and you are not trying to transfer huge amounts of power to the wheels.....

Personally I never had great luck with gpm parts....Your issue may not be with the diff but with the quality of the gpm diff....

what problems are you having that makes you want to go back???

Programmers
2007.07.14, 07:53 AM
Okie koke, thank you. I will give it a bash and see what I feel. I've got a track day due with a mate of mine so I can see how it runs then when compared to a ball diff.

Here's the problems I was having:

http://minizracer.com/forums/showthread.php?t=25640

bermbuster
2007.07.14, 08:45 AM
i even posted in that thread.....your ball diff is clicking....
the reality is you must change one part at a time to figure it out....
the seasoned guys here think it is in the gear teeth....first get a new gear...they are cheap and they are a wear part....you may want a new pinion as well.....
what happens if you stall the left wheel while running....(Hold car in hand and use your thumb) then the right wheel.....what happens when you back off the diff tension and do it? increase the diff tension and do it? this can help you pin point the clicking....

TALLGEESE
2007.07.14, 02:10 PM
Programmers, I was using the stock gear differential for HFAY racing last season and I had good results with it.. A lot of people swear by ball-diffs but I always thought it was an advantage using the gear diff instead because of the lighter weight for stock-class racing.. I have an old MR-01 GPM ball-diff and it's heavy, the only other diff I've seen that's almost as heavy is the PN ball-diff.. I think the reason the PN diff is a little heavy is because it uses 10 diff-balls in the differential instead of 6.. Like Kyosho's ball-diff... The PN ball-diff I saw didn't have a titanium shaft on it though.. Good luck on fixing your'e clicking problem..

color01
2007.07.14, 06:13 PM
I was checking GPM's website I think, there's also a titanium shaft for the stock gear diff. That would make the whole assembly pretty darn light and good for stock class racing.

A little diff grease to keep the diff from unloading too easily would probably be enough.

imxlr8ed
2007.07.15, 04:14 AM
I think for me... the biggest benefit of using the stock diff is the guarantee that you will always have the direct connection from trigger to track. As long as both tires are on the track firmly, almost all of the motors power is devoted to moving the car (If you've got good traction, of course). Bermbuster is right on the power issue vs stock diffs, I've switched only a few of my cars back to stock, with my Mod cars, I need the power to dissipate through diff slip.

I too, switched to a stock diff in HFAY, I felt I was losing just a hint of launch out of the corners with my ball diff, every little bit of speed you had with the RTR stock motors needed to go the track in HFAY Seasons 1,2 & 3. Plus there's a weight benefit as well. (I'm pretty sure there is, anyways)

With the new S4 Spec Motor though... I'm running one of my smoothest ball diffs. The new power might be a bit much for a stock diff on these tracks.

Programmers
2007.07.15, 06:11 AM
Fantastic info, cheers guys. I am gonna be running a stock diff until I get the new motor. A new diff isn't an option at the moment, so I'll just keep on trying to find the click in the old one. I'm sure it was the play...

herman
2007.07.16, 05:32 AM
Benefits of using a stock diff?
they are inexpensive....
you have no adjustments.....
The stock gears can work well if you have very good throttle control and you are not trying to transfer huge amounts of power to the wheels.....

to add... they're lighter than ball diffs... :D

Programmers
2007.07.20, 07:02 AM
My thoughts
I don't think I ever really give the stock diff a chance because it was stock, hehe. But after running it, I did way better than I did with a ball diff. It's perfect for my HFAY car even if it is bloody noisy.

bermbuster
2007.07.20, 10:47 AM
My thoughts
I don't think I ever really give the stock diff a chance because it was stock, hehe. But after running it, I did way better than I did with a ball diff. It's perfect for my HFAY car even if it is bloody noisy.
i agree....we are running the stock diffs in our nascars (oval racing) and they work pretty good......

HammerZ
2007.07.21, 01:58 AM
to add... they're lighter than ball diffs... :D

Very true, lower rotational mass.

arch2b
2007.08.05, 05:06 PM
the kiss pricipal favors the stock diff as well :) there is less to tweak, less to worry about. no debate abotu how tight/loose, no worrying about lost grub screws...

stock diffs can be very good provided they are taken care of. adjusting gear mesh is your biggest worry and as simply to do as inserting a sliver of paper at time.