BenAround

Hi all,

My actual name is Marty. I'm an old fart, having started mountain biking in the early 1980s when I was living in Fairfax, Calif, by the trails of Mt Tamalpais. I had done a bit of road biking before that, but after discovering the fire roads of Mt Tam, I was hooked and went out and bought a Specialized Stumpjumper, one of the early ones. I liked it a lot, but then decided to all out and bought a new bike down the street from my home, at a little bike shop called Fisher Mountain Bikes, run by Gary Fisher. I got a brand new 1985 Fisher Mt Tam, which I still ride.

I didn't ride for a bunch of years, but I'm trying to get back into it more, and did a bit of fixup on the bike, mainly just new tires, tubes, and liners so the tires wouldn't be flat every time I wanted to ride. It works well, except for my right shifter (Shimano Deore XT 6 speed), which probably needs either rebuilding or replacing, and this is not an easy task either way.

10 Wheels

Welcome from Texas.
Take it to your bike shop for help.

Zizkov

Welcome!

BenAround

Thanks, I never thought of that.

But I don't want to spend too much, and I can do the work if I can find a decent replacement. I plan to ask about it at the bike shops, but their prices might be more than I want to spend. Might be able to find a used one that works. Mine had a lot more use on it than many people.

curbtender

Welcome in. A lot of cool characters at the mountain bike museum. I bet they have a line on some old stock.

BenAround

Thanks, I'll check it out.

jccaclimber

No shortage of bicycle co-OP’s/bike kitchen sorts of places in SFBay. Many have fairly deep parts bins of older products and decent mechanical knowledge. One of them is likely the cheapest solution if you don’t want to pay new parts prices and aren’t afraid of elbow grease.

BenAround

Thanks, that's the sort of thing I would prefer. This bike has never been to a bike shop, although a good friend who moved away used to help me with some of the harder stuff. But I can replace and service brakes, shifters, etc. I'd take the shifter apart, clean, lube, etc except I'm afraid I won't be able to get it back together correctly - it's pretty complex, I know.

I never heard those terms, but searched and found a once-a-week bike kitchen a few miles away, in Concord. Unfortunately, it's a pretty bicycle-unfriendly ride to get there, but perhaps I can borrow a car that can transport the bike sometimes soon.

jccaclimber

The STI road shifters are a real bear to work inside of. The MTB ones, at least up to a few years ago, actually aren’t too bad, though some of them have a tiny spring that goes flying when you open them. Most of the time with old ones you can pop them open, give them a solvent flush, inject some fresh grease, and have them operational. If of course the ratchet components are damaged it’s easier to just replace the assembly.

curbtender

So, do you have a model number or picture?

BenAround

Of the bike or the shifter?

The bike is a Fisher Mt Tam Mountain Bike, built in 1985. The shifter is Shimano Deore XT SIS, possibly the first generation, from 1990 or earlier. I think it may be Shimano Deore XT SL-M730. Those look the same, and I can get them used for somewhere in the neighborhood of $75 or more.

I don't even care whether I have click shifters or friction. The one I have now works fine except for the lowest gear, which only works if I hold the shifter in place. Otherwise, the cable is too tight and pulls it down one gear. Of course, loosening the cable makes it lose the smallest gear and not skips sometimes.

My guess is there's dirt, moisture, and old lube inside, but maybe it's just worn too much from normal wear. I'm a bit of a wimp, and used the lowest gear a lot climbing the steep fire roads in my younger days living near Mt Tam in Marin County.

jccaclimber

I misinterpreted, that’s even older than I was picturing. That’s definitely a parts bin item, or equivalent. It could also just be a bent derailer hanger or something else similarly easy to fix. The local co-op should be able to straighten you out regardless.

curbtender

Could be the upper limit screw needs to be backed off a little. I checked thus rebuild video and it seems straight forward. No little springs to deform...

RadDadBikes

Hello Marty,
Welcome and cheers from Arizona... Moved here 3 years ago from Sacramento and originally from Redding.

BenAround

Thanks, but the problem isn't that it won't get on to the cog, which the limit screw would fix. It's that the shifter won't keep it there unless I keep pressure on the lever to hold it in place. When the cable is tight, it just can't hold it in place. I don't know if there is an adjustment that will help, but I'll find out when I get a chance to take it somewhere.

But in case I'm wrong, I'll try adjusting it again. By the way, I had watched that video, but thought it might be a bit risky unless I was ready or willing to get a new one if it didn't go back together.

BenAround

Thanks. Never spent any time in Arizona, just drove through long ago from New Orleans to California.

Barry2 

Sorry, Comments below reference trigger shifters.
Apparently yours are not of this type, my bad.

Barry


Shimano shifter grease has a reputation for drying out over time.
symptom being the ratchet sticks, gears change while you push lever, but change back when you release lever.
Flushing the shifter with WD40 while operating it will very often restore function.
you’ll find many posts regarding this in the mechanics section.

Flush while operating, let it soak for an hour or three, flush again, lubricate.

All the best and welcome

Barry

curbtender

Yes, on trigger shifters it's a problem. Looks like he has thumbies. I'd try loosening the cable and see if it is making that last click.

BenAround

I've tried adjusting the cable tension, but loosening the cable only helps it stay on the largest gear, but then doesn't shift properly to the other gears.

It shifts fine onto the large gear, but just won't stay there unless I keep pressure on the thumb shifter to hold it in place. I don't know enough about how the shifters work to know what keeps the tight cable from pulling it out of the low gear. Simple friction seems like it would be problematic, but I don't really know.

jccaclimber

Given the age of those shifters I wouldn’t be at all surprised if it’s just friction and detents.

BenAround

So, perhaps a good soak in WD40 or some other solvent might help? I suppose it probably wouldn't hurt, as long as I'm not too disappointed if it doesn't work.

jccaclimber

It might help and I highly doubt that it will hurt. Do give it a bit of longer lasting lubricant after.
My guess is that you have a worn out spring or detent, but it is truly amazing what refreshing old lubricants can to sometimes. Most greases don’t exactly perform properly after a decade or two. Even my still in the tub Park grease separated after less than that.

BenAround

In a former life, long ago, I worked repairing stereo equipment for a store that sold stereos. One of the first things I learned to fix was a record changer turntable. All that was required was to clean the old lubricant from the mechanism that had gotten hard from dust. Doing that taught me that dirt and grease don't mix well after a few years.

I do have a few different types of lubricants for different purposes, so I'm sure I have something that will work if I need it.

GFS

Hi Ben,
I can second the people above who highly recommend your flushing the shifter with WD-40 and then applying some good lubricant to the mechanism. I recently (like last weekend) bought a very nice Schwinn Moab 2 with Shimano Thumb shifters. The seller (a very nice Lady who upgraded to a Trek) explained in her listing that the shifters were only doing 1/2 of their shifting. Because of that, she was selling the thing for a ridiculously low price. After purchasing it, I went online and saw the recommendation to flush the mechanisms and then apply good lubricant. This is the exact same thing the LBS mechanic told me to do. After doing that, the shifters worked flawlessly.

Please note that you should FLUSH with WD-40 but NOT lubricate with it. WD-40 is not a lubricate. I used LPS 2 Lubricant which is a wonderfully good lube. YMMV, but just recommending.

Thank You, Gordon

BenAround

Thanks, Gordon. I plan to do this when I get a chance.

WD-40 is an interesting product. I would not say it's not a lubricant, although that's not its main purpose. Wikipedia says "It acts as a lubricant, rust preventative, penetrant and moisture displacer. There are specialized products that perform better than WD-40 in each of these uses, but WD-40's flexibility has given it fame as a jack of all trades.[3] WD-40 stands for Water Displacement, 40th formula."

But WD-40 is actually the name of the company, and they make a lot of spray products, some of which are much better at lubricating. There's silicone lube, dry lube, machine oil, etc. I kind of like the other products, because of their design, where you can use it as a wide-angle spray, or flip up a straw to do targeted spraying. It's much easier than the old fashioned separate straw that comes off or gets lost. I use the dry lubricant for my chain so it doesn't attract a lot of dust.