T-Cycle knows idlers, and we've pulled all the stops with our Elite Power 23 Tooth Idler. This idler is designed to last the lifetime of your bike, your trike, your velomobile and your house. Seriously, this thing is tough. Along with that toughness, we challenged ourselves to cut weight by removing every iota of unneeded material. And if that's not enough, this thing is intricately beautiful: CAD-perfected symmetry in rounded triangular corners, 23 holes that allow light through the space between each of the 23 precisely milled teeth, a cog that mimics the contours of the sideplates to add a sheen of metallic brilliance to the mix, and a clean, white lasermarked TerraCycle brandname to let people know you got the greatest quality available. This is truly the meeting ground of performance, beauty and reliability.
1. What makes this idler better than other big idlers?
The Elite Power 23 Tooth Idler is made of a solid metal core surrounded by a very light and ultra-durable sideplates. Your chain is carried on a specially shaped 6AL4V Titanium cog for maximum efficiency and long life. A heavy duty aluminum bearing carrier pressed inside the cog carries a pair of high quality bearings. It's tough, light, and really sharp looking. It's the ultimate idler for large power side idler application.
2. How big is the idler?
The 23T idler has an outside diameter of 4.0 inches, or 101.6mm. With 8mm bearings, this idler is a drop in replacement for most idlers of a similar size (HPVT, for instance). We make other idlers similar to this in 14T and 15T sizes (65 and 70mm OD, respectively). The 23T idler is the same thickness as our other Elite Power idlers, at 0.62 inches or 15.5mm.
3. I see it has bolts. Can I take it apart?
You can, but you shouldn't need to. They are held together with 6 stainless bolts. We do not recommend taking them apart. If they have many thousands of miles on them and you have reason to believe the bearings are finally worn out, please contact us. They are precision made and there are some steps to the disassembly/reassembly that are important to follow carefully. Since the bearings are pressed into the core, you will need a bearing press if you ever need to remove them. With any kind of reasonable care, the bearings should last tens of thousands of miles, though, and it would be rare to replace them. With a press, even a simple one, it's easy to do.
4. If I ever wear out the cog, can I replace that?
Yes, we can replace the cog assembly if that's ever necessary. We haven't had to do that yet, but with so many idlers out there, we're sure it will happen some day.
5. What about efficiency and noise?
We make exclusively toothed idlers for power side applications because they are both quieter and more efficient that way. There are a host of technical reasons for this, but the biggest and most basic one is that chains are designed to be carried by the bushings. It is a nice, big flat area designed for forces to be applied to. Chains are not meant to be carried on the edges of their sideplates. It just doesn't work as well. Since the core of the idler is all metal, from the chain bushings through to the bearings, there is no sponginess to soak up power. The chain sideplates aren't used to transmit power down into the idler, so there is no rubbing contact like there is on plain bedded idlers. Noise is a complicated issue, but we expect you'll find these idlers are quieter than other idlers. The cog is specially shaped to smoothly and repeatably mesh with the chain, and unless the chain is being pulled sideways quite a bit, there will be very little rubbing. We always recommend allowing your power side idler will float side to side with the chain as it shifts. Another common source of noise in drivetrains is insufficient contact on the idler. If there is not enough deflection of the chain at the idler, the chain and the idler don't have a chance to mesh properly. This is true for all types of idlers. You'd think that a chain only lightly touching an idler would be quieter, but because of the complex geometries involved, there is a minimum amount of bend or wrap required to get maximum silence. The amount varies with the diameter of the idler: the larger the idler, the smaller the angle required- so this idler is very quiet. Substituting this idler in for a smaller idler often solves stubborn noise issues with nearly straight chainlines.
6. What bearings can you get with these idlers?
We make these idlers with 8mm Hybrid Ceramic bearings (ceramic balls, stainless steel races), 10mm, 12mm, and 3/8" ABEC rated steel bearings. We can make them with 5/8" bearings also, but that is for a special version for some RANS bikes.
7. What's the difference between these idlers and the Sport Series idlers?
- Available with 8mm, 10mm, 12mm, 3/8, and 5/8 inch ID bearings. The 8mm bearings are hybrid ceramic, all the other sizes are top quality ABEC rated steel bearings. The most common bearing size on recumbents is 8mm. Some older bikes and trikes were made with 10mm idler shafts, and only a few bikes were ever made with 3/8" bearings. Some newer European bikes use 12mm bearings. Chances are you need 8mm bearings.
- This idler with 8mm bearings is a drop in replacement for the HP Velotechnik idler (our HPVT idler kit includes the necessary spacer to make sure the idler lines up on your original chainline). On a very few bikes, the seat mount is sometimes closer to the idler mount than others. If that is the case with you (and it is rare), we can replace the side plates and reduce the size of the idler 2mm.
- The cog is precision machined, but there is a break-in period while the cog and the chain get to know each other. After that, you can expect your idler to last many, many thousands of miles before needing service.
- We use stainless fasteners because we know you don't want things rusting.
- The titanium cog is 6AL/4V titanium, for the ultimate in durability. The cog and frame are extensively machined out for lightness.
- Weight: 135g
- Bearing Care: The bearings are shielded, not sealed. Shielded bearings have less rolling resistance because the seal, while super close, doesn't actually rub. True sealed bearings are rare, when people talk about "sealed bearings," they usually actually mean shielded. These are top quality shielded bearings and will last a long time. What kills bearings is solvent, dirt, and water intrusion. As long as you don't spray things on the bearing faces, you will be OK. Regular amounts of dust and dirt getting on the outsides of the bearings won't be a problem, as it's hard for it to get past the shields (the shields really do come very close to the bearings). When you clean them, what you want to do is gently wipe dirt off and away from bearings, rather than rub aggressively and push the dirt past the shields. There is no need to lube the bearings, the special grease that's in them is what they need.
- No maintenance should be required other than occasional cleaning with a paper towel or soft cloth. We recommend keeping solvents, soap and water away from the bearings; they don't need aggressive cleaning and solvents and soaps tend to go after the grease. It's water resistant, but solvents and soaps are harder to deal with.
- You will probably never need to disassemble your idler. Should you ever need to, a 2.5mm Allen wrench is all it takes.
- In general, we recommend setting up your idler so it can float side to side with the chain as you shift. This is somewhat less important with the larger 23T idler. If your existing idler mount doesn't allow for this, we offer a variety of upgrade parts to make this possible.
- The 23T is an upgrade replacement for many 100mm diameter idlers (HP Velotechnik and similar). 8mm is the most common bearing size. These idlers can also be ordered with 10mm, 12mm, 3/8, or 5/8 inch bearings.
Just the Medicine my bike needed!
Thanks Terracycles advice, my Raptobike is back on the road again- this time with no chain derailments. My M5 Lowracer will have a tighter turn radius thanks to mid-boom power and return idlers. Don’t know what the recumbent world would do without these guys. Hey, how about some recumbent-specific mounts for the Garmin Edge GPS series?
ICE & idler
I was quite pleased with the way it turned out. I had previously purchased an over/under set for the front, and eliminated all the tubes on my ICE Adventure HD. But there was too much slop in the chain, and it rubbed under load. This idler lowers the chain to eliminate the rubbing. I may yet use a piece of tube to tame the flopping of the return chain, but it's really pretty benign. Oh, and it looks good.
Outstanding craftsmanship on this idler. I foresee it lasting many years on my rides.
Very smooth and worth the money
I first installed them in my Alpha 7 velomobile and hated them because the idler mounts were not aligned with the chain line but then after installing them in my DF velomobile I found them to be as smooth and quiet as the factory plastic idlers with rubber (return only style) If you own a DF velomobile you have to try this titanium 23 tooth idler with 10 mm axle bearing, it will outlast the velomobile...
Thank you so much…