The Golden Boy 

I'm building a bike:

https://www.bikeforums.net/showthread.php?626894

My last step here is getting the thumb shifters. I had a SunTour Mighty Shifter on the right as the RD shifter, and I was temporarily using the left Suntour stem shifter for the FD.



It worked fine, but I wanted matching thumbshifters.

The other day I bought a set of SunTour Power Shifters off the Ebay, similar to these:




They're pretty obviously paired- they're mirror images of each other. They both appear to turn fine and ratchet well in the opposite direction.

I put them on the bike, installed them as the single shifter was installed, with the screw side in, clamp side out- new cable. The shifter switched across all gears, but it snapped right back through the ratchet to the smallest gear- as if there was no resistance against the derailleur spring tension. The front one worked fine. So I thought I might have them swapped around- so I swapped them so that the screw is outward and the band inward and the left is now the right... Now the RD works fine, but the FD snaps right to the smallest chainring- same thing it did on the other side.

I compared the ratcheting direction with the ratcheting SunTour shifters on my old Stumpjumper- on that one the left ratchets left and the right ratchets right. On these, they both ratchet to the left.

Is the shifter broken or is it assembled backwards or something?

IanHelgesen

Sounds like they're assembled backwards. The ratchet should be active when you are pulling the cable, with normal friction when you are letting it slack. If you unscrew that d-ring, you can take the shifter apart. You should be able to remove the ratchet wheel, flip it and the lever around, and re-assemble (this should make sense when you see how it's put together).

The Golden Boy 

Thank you Ian,

I'll take a look at that tonite after work.

Thanks!

mcgreivey

Or maybe you just need to tighten the tension, by turning that d-ring clockwise a smidge. Try that first (if you haven't already), before you tear them apart.

I don't think it's really possible to assemble them backwards, but I'd have to open mine up to remind myself...

Kimmo

OP mentioned it snapped back through the ratchet.

mcgreivey

Ah, OK.

Yeah, time to open it up and take a look. I guess I would open up both (the one that works and the one that doesn't) and see how they differ. Possibilities:
- ratchet wheel is upside-down
- washers were put in in the wrong order, or udside-down
- the spring-metal tab that engages the gnurlings on the ratchet wheel might be bent or broken

I guess there are other possibilities,,,

Here is an exploded view. This is a downtube set, but the ratchet mechanism is the same:
https://www.velo-pages.com/main.php?g2_itemId=12604
Actually, looking at it, parts #4 through #16 are the same as the thumb version (aside possibly from the length of the lever itself).

Part #10 is the ratchet wheel; #5 is the tab that engages the ratchet gnurlings on the ratchet wheel.

Part #16, the screw that holds it all together, on yours has a d-ring. Some have no d-ring, some have a plastic wing nut. No real functional diff.

The Golden Boy 

Oh wow, thank you!!!

I wasn't expecting that.

I'm really glad I didn't get the opportunity to get to the bike after work last night!

Just in what I'm reading here and seeing in the diagram, and not knowing exactly how a ratchet works- I'm guessing the ratchet wheel is upside down or backwards- so it's "teeth" are catching in the wrong direction. It totally makes sense- I initially had the shifters on the correct way so that the left shifter ratchets left (pulls cable to the left), but the right shifter is reversed from what it should be.

I don't know if I'm going to be able to get to it tonite or if it's going to have to be tomorrow... Rats.

Thank you very, very much.

mcgreivey

Are they new (NOS) shifters, or used?

They're not complicated--basically a pile of washers. There are no springs or anything that will go flying across the room and end up under the china cabinet that hasn't been moved for 50 years, in a pile of dust bunnies, beyond the reach of the beam of your flashlight or the reach of your yardstick.

I'd take the "bad" one apart and lay the parts out, in the order the came apart, on a paper towel, tops up. At least one of the washers is slightly domed, as I recall. I don't know if it matters if it's flipped, but it might. So I keep the tops up.

If you don't immediately see what's wrong, do the same with the "good" one, and see what's different. It takes me 10 minutes. 15 if I drop a washer on the floor and forget where it goes.

bikemore 

This is creative use, but I think these are stem mounted ratchets for a 5 speed.

mcgreivey

Not sure what you mean, but I think he has 10-speed (2x5, that is).

Suntour power ratchets were made in downtube, thumb, stem, and bar-end versions. The stem version is actually the cheapest and easiest to come by.

But this does raise a possible solution, if you find the "bad" thimb shifter is missing parts inside, or if something is broken: you could buy a stem-shifter version on ebay (probably $10-15) for parts to fix your bad thumby. Internally, they're basically the same.

The Golden Boy 

There's two things to report.

First.

I had sent the Ebay seller an email message and got a reply back from him saying that there must've been a mixup in cleaning and reassembling parts and he's sending me a new right shifter on his dime. That's absolutely awesome. I couldn't ask for any better customer service.

Second.

I did take the shifter apart this morning and found that each side shifter lever and housing is cast differently. So in other words, I can't just flip the rachet wheel and the ratchet catcher thingy and spring- the lever is cast to accept those parts in the way they need to be held for the ratchet to work in one direction.




There's two other issues that now have arisen out of this- one of the new shift cables is starting to fray, having been installed and removed 2-3 times. That's just a couple of bucks.

The other thing is that the cable clamp on the FD is now stripped out because I'm a dummy and tightened it too far. So I'm going to head up to the hardware store and get a nut to put on the other side so I don't have to buy a new FD. Hopefully that'll work.

This bike is an adventure.

mcgreivey

^^ I'd have to take one of my shifters apart to confirm this for sure, but everything looks in order in that picture. Did you compare the washers to the good shifter? If there's a missing washer, or if one of them is in the wrong order, or maybe upside-down, that could be causing the slippage.

But of course, if you have a replacement on the way, I suppose your problem is solved.

The Golden Boy 

FWIW, I received the lever today.

The Ebay seller, "paddythepeddler," sent the right part 1st class.

It's really awesome that he made good on his sale- I'd already left him positive feedback, it was a really cool move and I thank him.

As far as the bike goes...

I got a screw and a nut to clamp the cable to derailleur... it's tight.

After I got everything put back together I rode the bike up and down the street and was shifting gears- and it was very difficult to get the chain onto the big ring... Turns out the screw and nut are longer than the original, and that actually hits the body of the FD, making it difficult to go onto the big ring. Another problem to solve... Or maybe a new FD...

mcgreivey

It's great to have good Ebay experiences. All of mine have been, actually.

What's your FD? I sheared off my FD anchor bolt, and I took the derailleur off intending to take out the broken stub. I never got around to it, and I rode it around with no FD for close to 20 years. I shifted the front with my hand. I only shifted down to the small chainring for hills, anyway. I had better knees then. Ummmm or maybe my knees suck now because of that. I dunno.

I eventually got a new FD--a NOS Suntour, similar to the original. it only cost me $10 (on Ebay).

Anyway...

The Golden Boy 

I don't know that I could go without a FD. At least now.

Anyway, the derailleurs are Suntour AR from an old World Sport. It does work, you just have to wrench on it to get it to go over to the big ring. However... Back to the other issue with the crankset/chainrings...

I took it for around 16 miles (round trip) yesterday morning. The right shifter worked great. I have to do a little tweaking with the positioning... The chainrings... The small chainring is bent. Just a little. But just enough to allow the chain to get caught between the rings. I had probably shifted the front rings 4-5 times, maybe more- but then it got caught. That was a drag. I've finally figured out how to undo it (by rolling the bike backwards), but now I'm more seriously considering getting the BB on this bike tapped out to put in the cotterless crank and the rings from the World Sport.

My goal was to build up this bike for around $100. Right now, with the shifters, I think I'm around $140 (not that I've been keeping careful track). So the idea of spending another $30 isn't appealing, but the finish line is *right there!*

1987cp

Shameless bump and threadjack:

Today I came across an ancient Huffy mountainbike in an antique store featuring a set of Power Ratchet thumbshifters similar to those discussed in this thread. Trying to decide whether it'd be worth buying the thing for the $40 asking price and being stuck with yet another uninteresting frame and wheels and such to get rid of. The only other parts that really interested me were the Bullmoose-esque chromo handlebar (though not as good as a real Nitto Bullmoose because it has three straight sections instead of a continuous curve), and possibly the brake levers.

cs1

If you're getting handlebars, brake levers and shifters all for $40, I'd go for it. Sure, a Huffy for $10 is better but $40 for those parts alone is a good deal. Just scrap the bike or sell it for $5 on CL. Good luck

PHT

i say go for it. the nitto bullmoose bars look awesome but not everybody has that kind of money to spend on a set of bars... i was thinking of trying to find an old set on ebay but i came across some on an old apollo mtb at a yard sale.

besides, you can probably get it for less than the asking price?