Chainring Set

New-Old-Stock Shimano 600EX Biopace Chainrings...52x42 w/130mm BCD (Best Quality Oval-Style Rings We Have Available) Thank you for your interest in this item and please visit our store for other offerings. We have very reasonable shipping terms and combine orders to save money (for customers) on shipping costs. We also maintain customer friendly return/refund/exchange policies. Product Description: Listing Update...I have two nearly identical listings for like chainring sets. The only difference is cosmetic and concerns the label color. You will note on this chainring set, the label color on the large chainring is predominantly black/gray with white lettering. The nearly identical chainring set, which may be viewed at listing #272624492626, has large chainring labeling that is primarily blue/yellow with white lettering. I realize this may not make much difference to most, but I still thought I would make the distinction by allowing folks to choose between the two labeling differences in separate listings. Original Listing... This offering is for a new-old-stock Shimano 600EX Biopace chainring set finished in a an anodized brownish gray color. We've actually had a few customer comments regarding this color...with some believing the color is brown, while others believe the color is not a true brown and shows a hint of gray under certain light. I guess in the end, we'll stick with the brownish gray reference...with the emphasis on the brown color more than the gray color. I can also confirm the set includes an oval-shaped 52T model, an oval-shaped 42T model (both of which have a bolt-circle diameter (BCD) of 130 mm) and a complete set of chainring bolts. The chainrings were made from an aluminum alloy and date back to the early 80's. Both chainrings have beveled teeth and the 52T model includes a chain guard pin to help prevent an overshifted chain from lodging itself between the backside of the crankarm and this chainring. They are easily the best quality oval-style chainrings we have available, as the beveling/shape of their teeth is much more uniform and precise relative to lower quality Shimano chainrings. We are not entirely sure how much benefit this will provide while "on the road," but it's clear Shimano took more time and care in manufacturing these chainrings relative to some of their lower level chainring offerings. As for their specs., it worth reiterating their common BCD measurement makes them a good candidate for a number of Shimano double cranksets. Additionally, Shimano spec'd a number of their road triple cranksets with the same BCD measurement for the middle ring and outer (largest) ring, which provides other compatible options for this offering. Although, please do not consider these rings for a Shimano mountain bike triple cranksets, as they generally have a smaller BCD measurement. As noted above, these are 80's vintage chainrings...so they pre-date Shimano's SuperGlide chainrings (introduced in the early 90's). Atlhough (and upon closer inspection), the tooth design on these chainrings appears very similar to SuperGlide chainrings. The teeth on both types of rings are beveled to facilitate shifting, but the width of these older rings is thicker at the mounting points. Our best guess is the slightly thicker design was intentional and allowed for a wide enough gap between the rings (when mounted) to accomodate the thicker chains typically used on 5/6-speed drivetrains from this era. Please understand, this observation is focused primarily on the entire ring design and not necessarily the teeth...as the teeth on these chainrings are compatible with the relatively standard 1/2" x 3/32" chain. We also believe these chainrings may be used on any number of drivetrains (5, 6, 7, 8 and possibly even 9-speed drivetrains) with a compatible chain...meaning a chain with an appropriate external width for the intended drivetrain. If we had to make a recommendation, we would probably lean towards a 5 and 6-speed drivetrain first, but there is some flexibility here...as we have not encountered any problems when mounting these rings on 7 or 8-speed drivetrains. With respect to condition, they are new and unused...and although bulk-packed...they are still in fairly nice condition (with no signs of wear on any of the teeth). The chainring bolts are also fairly nice. We have a box of them and although some show signs of use (with slightly rounded allen bolt openings, the chrome is still nice and the bolts are still functional). Terms and Conditions: You may visit our store by clicking on this "Store Home Page" link and please note the product categories on the left side of our "Store Home Page". We have also moved our "Terms and Conditions" to a separate page within our Ebay store. You may navigate to this page by clicking on the link on the left side of our "Store Home Page" (below the product categories) or you may click on one of our "Terms and Conditions" direct links herein. Note to international customers regarding shipping... We apologize to those that feel some of our international shipping charges are too high. We only charge actual shipping rates, but once an order exceeds a certain amount, we hesitate to use the least expensive US Postal Services First Class International service. We feel this way, because this service is not trackable or insurable...so more risk of loss. We prefer the US Postal Services Priority Mail International service for more expensive orders, because this service is trackable at USPS.com and insurable...so less risk of loss. Unfortunately, this service is more expensive, especially for smaller/lighter packages, relative to the First Class International service. We are sorry about these higher shipping costs, but hopefully our notes help to explain why this is the case. Note to international customers regarding customs... We also apologize to those that feel their country import taxes, duties and brokerage fees are excessive. As a small US business, we are required by customs' laws to declare each order as a retail sale. Additionally, the declared order value must be equal to total store purchases and/or winning auction bids (less any shipping costs, as these are not considered in the declared value). As a result, each customer will be responsible for paying his/her own country taxes, duties and brokerage fees, which will be collected upon delivery. Again, we apologize for these additional costs, but we cannot afford the penalties and fines that come with breaking customs' laws...so we have to strictly abide by them.