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View Full Version : Rival doubletap spring tension adjustment/failure?



GuyContinental
10-05-2012, 07:45 AM
On my ride home yesterday my rear Rival Doubletap became super finicky about returning after a shift, it would physically stall about 10 mm from "home" position unless I coaxed it in with a finger. The result was a incomplete throw on subsequent shifts with predictably bad shifting. The set-up is pretty battered from many years and many many miles of CX abuse (mainly by others) so it wouldn't surprise me if it were something terminal in a component part.

I'm pretty new to SRAM road equipment and still figuring out the mechanicals and could use some advice- my immediate thought is that the return spring mechanism (however it works) has become unseated or is starting to go, from there I wonder if it could be a simple lubrication issue (I've never lubed the internals of a brifter but given the harsh life of a CX/all-weather commuter, perhaps I should(?) or a tired/snarled cable (it's the only un-replaced cable on the bike.

Thanks!

Guy

Dirt
10-05-2012, 10:02 AM
Rival and early Red had a few issues with use on Cross bikes because neither did really well when they got really dirty. My first generation RED stuff would freak out a bit after getting really pounded with dirt and sand. Second Generation stuff got better. Generally I found that flushing mine out with Clean Streak helped a lot. SRAM's web site had a video for flushing that stuff out a few years back that helped. When I did it, I used it as an opportunity to service the whole system. I took the hoods and bar tape off and removed the cables and housing because I was gonna replace all of that at the same time (more on that in a minute). If I recall correctly, once I got that all removed, it was a relatively easy process to spray it all out and get things moving well. I let it dry, then added a very small mount of lube to the key moving parts so they worked smoothly. If I recall correctly, I used Clean Streak to spray stuff out and Boeshield T9 (squeeze bottle form) to lube.

That said.... ANY time you have problems with return spring on a derailleur system, the culprit is often the cables and housing. Bikes that get ridden hard and in harsh conditions need new cables and housing once or twice per year. That's where the expensive, fancy pants, sealed cable and housing sets actually do us a disservice. We don't like spending $60 or more for fancy cables and housing and then throw it all away once or twice per year. If you can't throw it away, then spend $20 on bulk, Jagwire stuff and be done with it. You'll be more likely to change it regularly. Yokozuna cables are LOVELY when they are working as designed, but suck just as badly as any other worn cable system when past their duty cycle.

Cleaning the derailleurs and the guide under the bottom bracket (if you have one) with Clean Streak then lubing correctly is also a big help.

Does that help?

Pete

PS: I got through phases with my cleaning products. At times I really try to be green and use bio-friendly solvents and service products. They really are quite good. There are times, however, that some stubborn problems are seriously aided by using a bit of cleaner with Petroleum Distillates. I know... I'm a mockery of environmental leadership to say that. See what SRAM suggests... their service web site is better than most... If I recall correctly, using the powerful stuff really helped when I did this.

PPS: Clean Streak is my "Ozone Layer Destroying" solvent of choice. It works fast and easy so you can use a minimum of it. I like that they add a little orange smell to it now to fool you into thinking that it might be a bio degreaser. I'm pretty sure that is a total sham.