What is a Slipperential?

[brushlessboy16]

Ever consider a gear unit like the RRP Double disk, metal slipper pad with a plastic spur bolted to it?

[RC-Monster Mike]

Originally Posted by brushlessboy16

Ever consider a gear unit like the RRP Double disk, metal slipper pad with a plastic spur bolted to it?

Yes, we considered it - unfortunately, there is no room. We tried several ways to use a plastic spur in fact (the design started with a plastic spur). Our hardened pinions can withstand the abuse and run pretty quiet on the steel spur used. Would plastic work with the current design? - most likely, but a loose setting may cause failure. We had success with plastic spurs, but we had a heatsinking mount built into the spur, which added space and cost. The Steel spur is rugged, long lasting, and much simpler to work with.

[MetalMan]

I just ordered my Slipperential It will go in my Savage, and will be abused quite a bit! We'll see if Mike's hard word paid off

[jhautz]

OK... So mini review time. I put the slipperential in my truggy and went out to the local track this morning for some practice time and to see how this thing worked and how it effected the way the truggy drove.

I started off with the standard recommended setting of about 1.25mm gap between the plates on the slipper assembly. First lap with it and it was a noticeable difference. It made the very bottom end on take off from a stop or low speeds feel noticeably softer. I drove for the better part of a pack just trying to get a feel for how it reacted to hard launch conditions and the parts of the track that typically I used a quick snap of the throttle to clear a set of doubles and the hard acceleration out of the tight corners. It took a little getting used to at first, but after making an adjustment to my driving I got more comfortable with the feel.

I then pulled the truck off and did a quick temp test with my finger on the slipper assembly to see if was getting hot. It was for sure warm to the touch, but not as hot as the motor. (didn't have my temp gun in my pocket for that first run) But for sure didn't see any heat that concerned me.

After that first pack I started making adjustments loosening the slipper so it slipped more, and then adjusted it so it slipped more again until I had dialed so much slip into it and lost so much acceleration that I no longer could clear the triple on the back straight. It is a long triple. The nitros pretty much needed to land the small double right before it perfectly to set themselves up and get enough run up to clear it. Before dialing in all the slip I was actually easily able to overjump it with to hard of a throttle snap.

I figured that was about as loose as I could ever see anyone practically running it. I ran an entire pack thru it at this very loose setting trying to get a feel for it at this high slip setting. I also wanted to see how the clutch handled the high slip and what kind of heat would build up. After the pack (14-15 minutes) I quickly temped the slipper assembly and got a high reading of 116 degrees(F). Much cooler than I expected to see with running that much slip.

Next I started dialing back to the tight side with very little to no slip that I could detect. It basically felt just like it did with my normal diff. Tightening it down hard like that basically gave it no detectable slip at all I assume though that under a really hard hit like landing a jump with all 4 tires at the same time under throttle it would give just a bit and absorb some of the shock the motor would normally take.

Finally I spent a little time dialing it in to where it felt good to me. What I found that I liked might be a little more slip than what some others might want, but what I found it did for me was let me be more aggressive on the corner exits. With out the slipper I would have to carefully roll into the throttle coming out of the corner or risk having the back end break loose and step out on me. With the slipper set with just a bit of slip that corner exit became much less touchy. I did sacrifice a bit of the instant snap that would let you pretty much clear any jump on the track with no run up, but once I got the slip set where I liked it it seemed to be a good balance.

Thats about all I got to do with it today. A good little first try with it. So far I like it. Seems to be a solid unit that does just what its supposed to do. Looking forward to getting it on the track in a race condition so I can see if it actually helps with lap times. It seems like it will be a nice little tuning option. I can see it being very useful on the days where traction is low and having the smoothed out power curve on the bottom end will help keep everything in check.

So far so good Mike. Nice job.


(Crazy Side Note) After I got done playing with the slipperential in the truggy I took my buggy out for a few practice laps and wouldn't you know it... I broke the rotor loose from the motor shaft on my Neu. Probably just one to many drivetrain shocks. Gonna have to get it repaired now and then get a slipperential for the buggy too so I don't do that again. Talk about timing. I don't think Mike could have scripted that any better. LOL

[starscream]

I just bought a slipperential tonight.
I've got first place in the last two 8th scale races with my MBX5 (Ol' Faithful)
Hopefully the slipper will help smooth things out for that little extra advantage

Hey Mike,
Any word on optional spur sizes? 48/50/52?
I could use a little bigger spur for the RC8T

Thanks!

[Ryu James]

thats crazy about your buggy jhautz. talk about a selling point! i just ordered one and am anxious to try it out. i know i am gonna have to spend some time with it cuz i am just not used to having any slippage in my drivetrain. the guys who use clutches in their setups probably could find it easy to get used to this. in fact, that is a question i have Mike. how does the Slipperential work with a clutch setup like the Tekno kits run? does it essentially take the place of the clutch or could the two be run together?

i run direct drive and have tried Tekno's clutch setups and although i think they are great quality and work great i have preferred direct drive although i know there are benefits to having some "slip". like coming out of the corners like jhautz spoke of.

can the slipperential be compared to a clutch or are the two in completely different arenas?

[Maciolus]

Congarts Mike!

Could you please upload pdf file with instruction sheet?

[What's_nitro?]

Haha me too! My GTP will be the guinea pig...

Hey Mike- Any chance of a bevel gear version? You know, for a triple-slipperential setup?

[RC-Monster Mike]

The Slipperential will work fine with the clutch setup, Ryan - a bit redundant, but it would work perfectly fine. One thing to consider when using the clutch(and therefore mechanical brakes) with our Slipperential is that the slipper is built onto the diff cup - so if the front or rear brakes are actuated UNDER the center diff top plate, it will need to be moved to the top to avoid interference.
The Slipperential and Tekno clutch are two different means to a similar end result - though the behavior is different. I answered a similar question on another forum, so here is a copy/paste:

A nitro style clutch theoretically "disconnects" from the drive train at low/no rpm and engages up to "lock up" as rpms increase.
In practice, they both(Slipperential and nitro style clutch) offer drive train protection and traction control - just different ways of getting there and different "feel". The Slipperential is never "disconnected", so throttle response is instantaneous - direct drive(and also allows esc brakes and reverse). Power output/delivery can be tuned and the harsh shock to the drive train is minimized in either setup - just tuned differently. The Slipperential can be infinately adjusted in the vehicle by loosening the adjustment nut lock screw and turning the nut(adjusts like any other slipper really). The clutch setups are tuned with different clutch pads, springs, spring orientation, etc.

[jhautz]

To me the only thing similar in the slipper vs the nitro clutch is the fact that both protect the drivetrain from shock and smooth out the bottom end sharpness. I've driven them both now and they feel very different to me.

Nitro Clutch: The thing I didn't like about the nitro clutch was in low speed technical sections it lacks precision to me. It was hard for me to hit the throttle just the right amount the get the clutch to engage and the car to make the smaller acceleration. For me it was anyway. The nitro clutch does give allot of the same power management on the low end that helps prevent the traction loss on harder acceleration, and it also disconnects the drivetrain from the motor when you let go of the gas and it allows the car to coast allot better.The disengaged drive train is something that the slipper will not do and some like that driving characteristic. (good or bad, you decide). Requires the use of mechanical breaks

Slipper Clutch: Keeps the very connected feeling for me, making the lower speed drivability in the technical sections easier for me. It didn't really feel any different than direct drive with no clutch in this area. Adds the benefit of smoothing out the bottom end snap to help maintain traction on heavy acceleration like the nitro clutch. It does not disconnect the motor from he drivetrain when off throttle so the coasting characteristics are the same as a direct drive (good or bad, you decide) Allows the use of simple motor breaks or mechanical breaks with the right setup.

One other thing I did notice yesterday while playing with the slipperential is it not only effected the sharpness of the hard acceleration, but it also effected the braking a little using the motor brakes. Made it harder to lock up the the brakes when coming into a sharp corner under heavy braking. The slipper seems to absorb the initial impact that slamming on the brakes creates. The initial hard hit of the breaks seems to be what breaks the tires traction and starts then skidding and once once they are skidding its hard to get them back. So there may be a breaking benefit for the slipperential also. It could also be a negative for those that like to slam on the breaks, slide into a corner and then throttle out of it. I'll have to do some more playing with it to see how the adjustment effects the braking exactly. It was more of just an observation of a side effect at this point, but something that could be interesting.

[Ryu James]

Originally Posted by RC-Monster Mike

The Slipperential will work fine with the clutch setup, Ryan - a bit redundant, but it would work perfectly fine. One thing to consider when using the clutch(and therefore mechanical brakes) with our Slipperential is that the slipper is built onto the diff cup - so if the front or rear brakes are actuated UNDER the center diff top plate, it will need to be moved to the top to avoid interference.
The Slipperential and Tekno clutch are two different means to a similar end result - though the behavior is different. I answered a similar question on another forum, so here is a copy/paste:

A nitro style clutch theoretically "disconnects" from the drive train at low/no rpm and engages up to "lock up" as rpms increase.
In practice, they both(Slipperential and nitro style clutch) offer drive train protection and traction control - just different ways of getting there and different "feel". The Slipperential is never "disconnected", so throttle response is instantaneous - direct drive(and also allows esc brakes and reverse). Power output/delivery can be tuned and the harsh shock to the drive train is minimized in either setup - just tuned differently. The Slipperential can be infinately adjusted in the vehicle by loosening the adjustment nut lock screw and turning the nut(adjusts like any other slipper really). The clutch setups are tuned with different clutch pads, springs, spring orientation, etc.

thanks Mike. that explains things perfectly. sorry if you posted that somewhere already. i didnt see it and this was my first time reading anything about your slipperential. it sounds like the slipperential will be more up my alley. i cant wait. the way jhautz described his comparison of the clutch and the slipperential makes sense and i can relate. i didnt like the disconnected feel from the drivetrain at low speeds and and it just didnt "feel" right to me. just my preference. but understanding now that the slipperential keeps the drivetrain always engaged while providing adjustable slip to smooth out take-off and out-of-corner acceleration sounds like the perfect combo to me.

also, jhautz mentioned the effect the slipperential has on braking; how it is hard to lock the brakes up with the esc brakes. he said it could be a positive or negative effect i guess depending on your driving style. for me, i like to lock up my rear wheels going into a SHARP turn but i use mechanical brakes so it wont be an issue at all.

i am plannin to run in the brushless buggy open class at the Silver State RC Race in Las Vegas this weekend. i imagine i might be the only one there with a slipperential since it just came out. i am pretty new to competitive racing but i cant wait to try it out and also show it to everyone. get some good exposure. anyone else going to be there with a slipperential?

[jhautz]

Originally Posted by Ryu James

also, jhautz mentioned the effect the slipperential has on braking; how it is hard to lock the brakes up with the esc brakes. he said it could be a positive or negative effect i guess depending on your driving style. for me, i like to lock up my rear wheels going into a SHARP turn but i use mechanical brakes so it wont be an issue at all.

Please remember, I had my truggy brakes set up before I put the slipperential into it. It was tuned so I could just barly lock up the tires comming into the hard corners when using the direct drive. My brake epa is set to only 64% so there is alot of braking left to dial in if you want more braking. Please dont think that you cant lock up the tires, it just seemed to take the edge off of the brakes is all. I havent spent ay time trying to tune the brakes with the slipperential, the brake comment was just a side note observation. My initial feeling was I liked the feel of the slightly less touchy feeling brake, but if I wanted more I'm sure I could have dialed more in. I just havent gotten to playing with it yet.

[himalaya]

Mike have you ever considered (if possible) to further integrate more features into your proud product? something like Losi's smartdiff or torsion diffs ? that will make the slipperential ultimately perfect.

[Finnster]

I was reading the product description I couldn't find a few specifications that would be handy to those looking, esp as word gets out and casual customers come looking and don't necc browse the threads. Specifically the tooth count of the spur (sounds like only 46 is avail now) as well as the diameter for the bearings. I'm assuming std 8mm.

The later isn't critical, but would be nice as it says you need bearings to fit your app.

[Arct1k]

Just a idea but might be good to have available for purchase sets of shims for the centre diff in the shop...

Then include within construction guide how to shim centre diff correctly.