DK308 219 Posted May 1, 2019 Hiya all Has anyone here any experiences with the Tamiya TRF PTFE sealed bearings? I can see that they are supplied with the TRF41X onroad cars, but not with the TRF offroad rigs. Do they work poorly offroad or what's the deal? All and any info on this is welcome. Thanks guys. Share this post Link to post Share on other sites
speedy_w_beans 4270 Posted May 1, 2019 Tamiya was probably trying to optimize on low torque / low friction characteristics with type L seals: shield type link If you look at the cross sections of the bearings, the Buna-N (type D) and Viton (type D1) seals are what we normally call "rubber shielded" bearings. Those get used for off-road. Note there are PTFE seals (Q and Q4) that seem better at sealing than the type L seals. If you look at ball bearing listings on eBay there are many with seal/shield codes in them (ZZ, for example). Some of these are optimized for friction/torque, others for sealing characteristics... You can read all day about ball bearings in some of these catalogs: NTN and SKF/MRC 2 Share this post Link to post Share on other sites
Jonathon Gillham 4595 Posted May 1, 2019 I usee some 1510's I had for my TA07 diffs on my sons HB D413 in the rear hubs. Lasted months, compared to my Kyoshos running standard bearings and 2 1/2 years in there hasn't been a single failure. They had that fibreglass look to the shields. I didn't want to use them as they are expensive but they were all I had available at the time. One actually fell apart when I tried to remove it and I had to pry the inner race off the axle. That link Speedy posted suggests there are different versions of them, some which seal better so maybe some would work fine. Mine were sold in pairs for the diffs so I guess were the wrong type 1 Share this post Link to post Share on other sites
DK308 219 Posted May 1, 2019 3 hours ago, speedy_w_beans said: Tamiya was probably trying to optimize on low torque / low friction characteristics with type L seals: shield type link If you look at the cross sections of the bearings, the Buna-N (type D) and Viton (type D1) seals are what we normally call "rubber shielded" bearings. Those get used for off-road. Note there are PTFE seals (Q and Q4) that seem better at sealing than the type L seals. If you look at ball bearing listings on eBay there are many with seal/shield codes in them (ZZ, for example). Some of these are optimized for friction/torque, others for sealing characteristics... You can read all day about ball bearings in some of these catalogs: NTN and SKF/MRC Yeah, I've tried to read as much as I mustered. But I reckon the PTFE bearings are more for the onroad stuff rather than offroad it would seem.Thank you for the links. 2 hours ago, Jonathon Gillham said: I usee some 1510's I had for my TA07 diffs on my sons HB D413 in the rear hubs. Lasted months, compared to my Kyoshos running standard bearings and 2 1/2 years in there hasn't been a single failure. They had that fibreglass look to the shields. I didn't want to use them as they are expensive but they were all I had available at the time. One actually fell apart when I tried to remove it and I had to pry the inner race off the axle. That link Speedy posted suggests there are different versions of them, some which seal better so maybe some would work fine. Mine were sold in pairs for the diffs so I guess were the wrong type Thank you. That's the kind of stuff I wanted to hear about. I think I will stick to rubber sealed ceramic bearings for "external" offroad use, and metal shielded ceramic bearings inside gearboxes etc. where things spin fast and get hot. Share this post Link to post Share on other sites