Attic What IZIT #15
by Bikeman • September 13, 2023
We had a lot of fun with the Attic What IZIT back in the day. We'd dig up some of the more obscure parts hiding here and put it out to our loyal visitors to come up with what it is. Bikeman would always know of course but it was entertaining to see how long it would take for someone else to come up with the correct answer. We would post the answer so the winner could take a victory lap. In the event of multiple correct answers we would post the most complete or creative one. We'll try to dust one of these off each week and keep the excitement going of what will pop up next.
Originally Published early in this century
A new relic from the attic has surfaced. This one isn't very hard if you think on it a bit. What might be hard is coming up with the maker of the product and a good description of the pros and cons associated with the item. As always the best answer wins and bonus points for personal experience or a picture of your bike with this item in use.
This edition provided us with several excellent answers to choose from. In the end it came down to personal experience with the product that put him over the top.
The Winner is Chet Lewinski
"This is a chain tensioner manufactured by Bullet Brothers. Circa 1996? This item bolted between the rear derailleur and the frame using the same mounting bolt. The arm then extended beyond the frame, a spring attached to the arm was then stretched and mounted to the derailleur cage just behind the lower pulley -you know the chain guide tab just behind the pulley. This device was designed to increase chain tension and reduce the dreaded chain suck problem. This product was originally targeted to downhillers at the time but was also a popular add on item for those of us who insisted on running Gripshift SRT/X-ray shifters with a Shimano derailleur. This helped compensate for the extra cable drag caused by early twisters and weak return springs. In addition to running one of these I also used a Gripshift Bassworm and a stronger after market spring produced by Sidetrack, even with all these accessories shifting was still inconsistent at best. Boy, there sure was a lot of snake oil being sold back in the day!" .... A Bassworm reference will always help your chances.
Runner Up #1: Geoff Yeo
"Isn't that the old bullet bros' chain tensioner from the late '90s? It attaches to the bottom of the RD cage with a spring pulling it backwards to keep stuff from slapping around. Good idea, but the thing was hanging off the back in the way of um... trail hazards?... Other chain tensioners that involved rollers (like the early Kore ones) faired better. ....let me add this: it may have helped chain suck, but it also made your shifting suck."
Runner Up #2: Steve Bodayla
"This looks like a Bullet Bros. chain tension system, a.k.a. "Chain Bub Hypertension System." It was supposed to eliminate chain slap and keep the chain from falling off the front chainrings, but it mostly just added friction by applying tension to the chain, and provided something else for brush to get tangled on.."
Runner Up #3: Anthony Azzara
"That's a Bullet Brothers (Bullet Bros?) Chain tensioner! That arm was positioned to sick out behind the rear derailleur, and the spring pulled the derailleur backwards, adding more tension. This supposedly increased chain tension to keep the chain on on rough downhills. Came in some funky ano colors too, I think."
Runner Up #4: Wayne Chang (Attic #14 Winner)
"This is a stab in the dark. I donated this part to the Trips for Kids Bike Shop some 10 or 12 years ago. for the lack of a proper name, it was called a Thingamajig made by Precision Manufacturing. I'm pulling shite out of the arse now. It was attached on the rear wheel skewer to provide spring tension to keep the derailleur hanger back which helped the chain stay taut preventing excessive chainslap. The kit came with 2 springs, one tighter than the other depending on how much tension you wanted. you would install one and pretty much lose the other minutes later. Since this was an early 90's part it was CNC'd out of aluminum and anodized to the snazziest rave colors available. Mine was the violet purple that Grafton used so often.."
Runner Up #5: Mark "Tex" Logrbrinck
"It is a tensioner for the rear derailleur, you bolted it on your quick release. The black clip hooks on to the cage at the lower deraillueur pulley. The spring gave tension to keep the chain from falling off in rough sections. I thought of buying one, never did. Don't know who made it. Oh yeah are Bikeman Team members not eligible? and you are right it was an easy "what iz it". ....yes, team members who have not been in the shop and seen the item are eligible. We keep the items locked up in a safe place until the listing is over to keep it from would be "Attic Spies".