Designed for super efficiency, super durability, and super price!
Get the higher efficiency of a larger 23T idler, but in our value priced SportPlus Series. This idler has it all: great efficiency, great looks, tremendous ruggedness, and great price. It features the same new specially designed beveled sideplate shape as our Elite Series 23T idler, but the sides aren't machined from a solid block of aluminum and it doesn't have the Elite's titanium cog or ceramic bearings. So you get exceptionally smooth chainflow, a very durable 7075 Aluminum cog, very nice ABEC 7 bearings, and super tough glass filled nylon sideplates, all at a much lower price.
Available with 8mm ABEC 7 bearings, or high quality 10mm or 3/8 inch or 5/8 inch bearings. Matching stainless chainkeepers available with 6mm or 8mm mounting holes.
1. Why this idler?
Larger idlers are quieter and more efficient. Until now, we only offered a 23T version in our Elite line. The Elite line is very nice, but expensive. This idler brings many of the performance advantages of a larger idler at a much lower price.
2. Why are larger idlers quieter and more efficient?
Larger idlers are quieter because the geometry of a 23 sided polygon is a closer approximation to a true circle than a 15 sided polygon. It has to do with the arc error between a polygon with the same number of sides as the number of teeth of the idler. Larger idlers have less arc error, and the chain moves more smoothly over them. Larger idlers are more efficient primarily because each link of the chain doesn't bend as much as it comes on and off the idler. The smaller the idler, the more each link has to bend.
3. Will this fit my bike or trike?
If you have a bike or trike with an approximately 100mm diameter idler already, this should be a drop in replacement. Just be sure to order it with matching bearings to your old one. On a few HP Velotechnik bikes and trikes, the distance between the idler mount and the seat mount is slightly smaller for some reason. For those situations, we make a version that is slightly smaller (and the same size as the stock idler). If you are upgrading a bike or trike with a smaller idler, you need to check that the idler will clear other things near the idler mount, and check to make sure that moving the chainline down a bit doesn't cause interference with the frame or steering linkage.
4. What is the "specially designed beveled sideplate shape" and why is it important?
Part of the role of the sideplates is to keep the chain from derailing off the cog if anything bad happens (a big bump, a bad shift, etc.). To do this, the sideplates have to be as near to the cog as possible, but still allow the chain to come into the idler from the side, because some chainlines don't allow the chain to always come in straight. With a larger idler, the sideplates don't curve out of the way of the chain like they do with a smaller idler. The usual thing is to move the sideplates out on a larger idler, but that reduces the chain control. We used computer modelling and real world testing to design a special angled shape to the inside of the sideplates that both keeps the chain from rubbing in normal use, but is right there to keep the chain in place if anything unusual starts to happen. It is very effective at reducing or eliminating chain derailments.
- Tough glass filled nylon sideplates have a specially shaped inner surface to guide the chain back onto the cog if it ever tries to derail. Compatible with 7, 8, 9, 10, and 11 speed chains.
- Precision machined 7075 Aluminum cog.
- All metal core construction, the chain loads are carried in metal all the way to the bearings.
- Stainless bolts and Nylock nuts.
- Outer Diameter is 99.6mm, but a 98mm version is available for HPVT products where the seat mount is close to the idler mount.
- Weight is 113g with the 8mm ABEC 7 bearings.
- Check the clearances to the idler to see what spacers are required. If possible, allow the idler to float from side to side so it can track with the chain as you shift.
- Fits on any bike or trike where a larger, approximately 100mm diameter idler will fit. On certain HPVT bikes and trikes, the seat mount is closer to the idler mount than usual. For those bikes and trikes, we make a slightly smaller diameter version. Be sure to request the smaller version if there is any question of using the standard sized idler.