ThunderDragonCy 7881 Posted July 6, 2018 Got the 8.5t brushless and core RC Lipo in the DB01R today and gave it first run. The whole time I was getting a lot of slipping on the slipper clutch, and tightening it didn't seem to help. I have pretty much zero experience with these but the manual setting is way less preload than I have, and it has the upgrade black spring. Bought it 2nd hand so could be the slipper is knackered. Is this glazed pads? If so, can someone recommend replacements? The TRF501 pads are easily available but most reviews I have seen seem to say ditch the tamiya pads. Is this really a thing, or just people having preferred brands for transmission parts? Any help much appreciated. Thanks. Share this post Link to post Share on other sites
markbt73 5316 Posted July 6, 2018 I don't know about that particular car's design, but yes, slipper pads can get glazed. Sometimes you can breathe new life into them with a gentle application of sandpaper, or by scraping the glazing off with an X-Acto knife. Can't help you with the brand. I didn't know aftermarket slipper pads were a thing. Whether you try to refresh them or replace them, pay attention to the manual when you reassemble it. Someone may have put a spacer or a washer in the wrong place that kept it from tightening properly. Also, if they're available, I would replace the spring while you have it apart, as well as any of those wavy "spring washers" if it has them. They could have lost their spring, especially if both you and the previous owner kept cranking down the nut to stop it from slipping. 1 Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted July 6, 2018 Thanks for the advice. I think I found a big part of the problem though Have I mentioned how much I hate ball diffs? 1 Share this post Link to post Share on other sites
Wooders28 4723 Posted July 6, 2018 21 minutes ago, ThunderDragonCy said: Thanks for the advice. I think I found a big part of the problem though Have I mentioned how much I hate ball diffs? Guessing the slipper is fine and it was the ball diff slipping? I'm not a great fan of ball diffs either, and not needed if you've got grip, ive upgraded to a gear diff in a schumacher car and use heavier diff oil if i needed. Share this post Link to post Share on other sites
markbt73 5316 Posted July 6, 2018 Wow. I'm not sure I've ever seen one melted down quite like that. Pretty impressive, actually... Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted July 6, 2018 1 hour ago, Wooders28 said: Guessing the slipper is fine and it was the ball diff slipping? I'm not a great fan of ball diffs either, and not needed if you've got grip, ive upgraded to a gear diff in a schumacher car and use heavier diff oil if i needed. Well if the front one that's now in the back goes the same way I know what it's getting replaced with. 1 hour ago, markbt73 said: Wow. I'm not sure I've ever seen one melted down quite like that. Pretty impressive, actually... Indeed. Makes me think it was ******* from the start. 1 Share this post Link to post Share on other sites
speedy_w_beans 4272 Posted July 6, 2018 I think you just achieved a new record for the most melted ball diff! I've never seen one in that condition before. Sounds like your slipper is just fine... 1 Share this post Link to post Share on other sites
Rb4276 803 Posted July 6, 2018 I melted mine in my dn01 when i first went brushless. I had to gear down to 25t pinion and 77t spur. I was using 30t and 69 spur the car was going over 50mph when it melted with a castle 4600kv Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted July 6, 2018 Just now, Rb4276 said: I melted mine in my dn01 when i first went brushless. I had to gear down to 25t pinion and 77t spur. I was using 30t and 69 spur the car was going over 50mph when it melted with a castle 4600kv Probably is a little over geared with 4400kv and 25/91, but looking at the gear chart and advice on gearing probably only needs to be 21/91 really. Share this post Link to post Share on other sites
Juls1 1661 Posted July 7, 2018 I had the same issue with my dn01, thought it was the slipper, but it was the diff! The upside is the db01rrr has gear diffs so in theory......... Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted July 7, 2018 7 hours ago, Juls1 said: I had the same issue with my dn01, thought it was the slipper, but it was the diff! The upside is the db01rrr has gear diffs so in theory......... There is definitely a gear diff option. That is next if the other ball diff doesn't last Share this post Link to post Share on other sites
Juls1 1661 Posted July 7, 2018 I thought you where getting a front one way? Juls Share this post Link to post Share on other sites
super gripper 419 Posted July 7, 2018 I build ball diff's for people, I get them in the post all the time. Tamiya ball diff's are awesome but people run them too loose. Also do not get the gear diff's they are pants unless you spends lots of money on them - running around in your garden won't tax them but if you race they break - a lot …………….and yes you should have been using a 19 tooth pinion on a 91 spur gear - yes I am a racer ! Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted July 7, 2018 2 hours ago, Juls1 said: I thought you where getting a front one way? Juls I am. This is the rear diff. Front ball diff has been replaced by the one way and that ball diff is now in the rear. Share this post Link to post Share on other sites
Britaff 28 Posted July 7, 2018 You are not alone with this problem, I’ve just pulled this from the back of my garden brasher baldre. It’s running a 2s lipo and an 8.5t etronix combo but hasn’t been run on this for very long. it was so funny to see the poor thing trying to move on only front wheel drive. I guess I’m running the wrong gear ratio too so I’ll order standard parts and take the advice from supper gripper(thanks matey) and get the correct pinion size Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted July 7, 2018 That looks all too familiar. Gearing definitely needs a look, but smaller pinion will increase the torque in the drivetrain so if anything it will make the situation worse for the diff. Just need to make sure it is super tight before running and back the slipper right off. Annoying thing with mine was that people go on about diffs 'barking' but the noise was completely smooth like a slipper. I had no idea what was going on. Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted July 7, 2018 Double post Share this post Link to post Share on other sites
Britaff 28 Posted July 7, 2018 Yeah mine made no noise at all when it went either it just seemed to smooth out of power if you get what I mean i haven’t got a slipper in mine it’s bog standard but I’m running the 17tooth pinion, I’ve ordered the 19tooth suggested by super gripper and all the parts to rebuild it so I’ll make sure it’s nice and tight and see how it goes Share this post Link to post Share on other sites
super gripper 419 Posted July 7, 2018 do not slacken the slipper right off you will cook it. Run the slipper as per the manual - also bin the DB01 diff parts and get the trf501x one piece diff halves - I know what I am talking about people - picture of my race winning DB01R …………… I race a TRF502x now. 1 Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted July 7, 2018 1 hour ago, Britaff said: Yeah mine made no noise at all when it went either it just seemed to smooth out of power if you get what I mean i haven’t got a slipper in mine it’s bog standard but I’m running the 17tooth pinion, I’ve ordered the 19tooth suggested by super gripper and all the parts to rebuild it so I’ll make sure it’s nice and tight and see how it goes My buggy is second hand and came with a 25t pinion so opposite to your buggy. Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted July 8, 2018 14 hours ago, super gripper said: I build ball diff's for people, I get them in the post all the time. Tamiya ball diff's are awesome but people run them too loose. Also do not get the gear diff's they are pants unless you spends lots of money on them - running around in your garden won't tax them but if you race they break - a lot …………….and yes you should have been using a 19 tooth pinion on a 91 spur gear - yes I am a racer ! How tight should I be running it? I set it so when holding the spur and the right wheel the left wheel just didn't turn under a light spin. I am guessing go way tighter? Share this post Link to post Share on other sites
super gripper 419 Posted July 8, 2018 2 hours ago, ThunderDragonCy said: How tight should I be running it? I set it so when holding the spur and the right wheel the left wheel just didn't turn under a light spin. I am guessing go way tighter? building ball diff's is an art in itself. I have a ridiculous amount of experience building and setting up Tamiya ball diff's. Build the ball diff exactly as per the Tamiya instructions but I recommend using Associated ball diff lube as it is slightly thicker than the Tamiya stuff - the Tamiya one goes very running almost like water when it gets hot. The AE stuff stays where you need it for longer - at no point should you ever believe that once the ball diff is built is a forget thing - it will require a full strip and rebuild after about 25 - 30 runs. The 6 screws that hold the rear gearbox cover piece on change to 3mm hex bolts as you will be in and out of there plenty. - the same goes for the centre section. - Right in answer to your tightness question. - build it as per kit instructions. when you hold the ball diff you should be able to turn it holding the exits and it should feel stiff - if it grinds then it is too tight - next fit it in the car and put the car back together - once all back together when you hold one wheel and turn so you rotate the ball diff it should feel smooth but tight - when you try and spin it by hand the wheel should only remote half a turn ……………… hope all this helps - reading what you say you are testing wrongly - hold the spur only - hold the left or right wheel and spin it - the diff should only rotate half a turn once you let go 1 Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted July 8, 2018 3 hours ago, super gripper said: building ball diff's is an art in itself. I have a ridiculous amount of experience building and setting up Tamiya ball diff's. Build the ball diff exactly as per the Tamiya instructions but I recommend using Associated ball diff lube as it is slightly thicker than the Tamiya stuff - the Tamiya one goes very running almost like water when it gets hot. The AE stuff stays where you need it for longer - at no point should you ever believe that once the ball diff is built is a forget thing - it will require a full strip and rebuild after about 25 - 30 runs. The 6 screws that hold the rear gearbox cover piece on change to 3mm hex bolts as you will be in and out of there plenty. - the same goes for the centre section. - Right in answer to your tightness question. - build it as per kit instructions. when you hold the ball diff you should be able to turn it holding the exits and it should feel stiff - if it grinds then it is too tight - next fit it in the car and put the car back together - once all back together when you hold one wheel and turn so you rotate the ball diff it should feel smooth but tight - when you try and spin it by hand the wheel should only remote half a turn ……………… hope all this helps - reading what you say you are testing wrongly - hold the spur only - hold the left or right wheel and spin it - the diff should only rotate half a turn once you let go Nice one. Thanks. I'll give that a go. Share this post Link to post Share on other sites
ThunderDragonCy 7881 Posted July 11, 2018 Well, I got the car together today and gave it a run. Tightened the rear diff as advised and it seemed to work. It definitely started to come loose after about 5 minutes though so I stopped to tighten again and ran some more. Got a bit paranoid about melting it so stopped and came home. Just pulled it out and it's fine. Still smooth. It is quite greasy though so I think I am going to strip, clean and rebuild it with fresh grease. I have some ansmann diff grease already. Fingers crossed. Share this post Link to post Share on other sites
markbt73 5316 Posted July 11, 2018 Wow, are modern Tamiya ball diffs really that fragile and fussy? I've only ever had them in TA01/02/03 cars, and those were build-it-and-forget-it. Same with every Associated Stealth diff I ever had, although the thrust bearings get crunchy in those after a while. Seems like a pretty glaring design/engineering flaw on Tamiya's part... Share this post Link to post Share on other sites