JTSpeedDemon

So, My 10 speed Kent with friction shifting is riding nice finally, but I've got a problem.

The lowest(biggest) 3 rear cogs work great, along with the rest of the transmission, but when I try to upshift to the highest 2 rear cogs, nothing happens. The shifter cable end will just poke out of the shifter, and the rear derailleur might upshift if it feels like it.

All the other shifting works fine, but it just does not want to shift to the 2 highest gears.

Do I need to put the shifter in the highest gear position and tighten the cable? That's what I plan to do.
Or is my derailleur just shot?


I'm handy with a wrench and many other tools, I'm just figuring out how to tweak the bike.

Wilfred Laurier

It is likely either cable friction in the last loop of housing near the derailleur, or the end-point limit screws need adjusting.

In general, the end point screws should be the first part of the derailleur to adjust. Set the 'high' limit screw so the chain easily and quickly drops onto the small cog when there is no cable tension, and set the low limit screw so when turning the cranks and pushing ont he derailleur with your thumb you can get it into the largest cog but not go past.

Retro Grouch 

How long has it been that way? Did you install a new cable or anything that might have made that happen?

Before doing anything else, try this:
1. Shift into a gear combination that makes the derailleur cage going straight, or nearly straight down.
2. Stand your bike up against something and look at the derailleur from the back.
3. Does the derailleur arm seem to be pointing toward the back tire? If so, that's the problem. It should be pointing straight down. You will probably be able to bend the whole thing back using just your hands. Try that, see if it fixes your problem, and cost back if it doesn't.

alcjphil

In cases like this the problem is almost always excessive cable friction. You can easily test this by disconnecting the cable from the derailleur to see if the derailleur will then shift the chain to the smallest cog. If it does so, you have to either lubricate or replace the cable and casing.

bikeaddiction1

OP, do this first as recommended. If your derailleur or hanger are bent everything else you do is futile.

Andrew R Stewart 

I will sometimes disconnect the cable from the der and then see how each works independently of each other. The der should be able to be pushed/pulled through it's range with only your fingers, easer done with the bike off the ground so you can pedal with the right hand and move the der with the left hand. By holding the end of the cable, tugging on it slightly, the shift lever can then be moved through it's range and the cable should freely follow the lever's take up and play out.

But as already mentioned check that the der is hanging down off the drop out fairly vertically. I sometimes will place a straight edge (straight side of a wrench, ruler...) against one of the mid/larger rear cogs and sight along that to compare the der's cage alignment. Andy

Bill Kapaun

What's the "back story"?
It sounds like an old bike that was stored for years and needs the cables & DER's cleaned & lubed or even replaced. (this bike had low level parts when new)
Move the shifter to the highest gear.
There should be slack in the cable.
Physically push the RDER to see if it moves into the proper position. IF it does, yo u know you have an excessive friction problem.
It's just the RDER spring tension that allows it to move to the higher gears.

JTSpeedDemon

Thanks for the replies everyone!

As far as the back story, I got it from a scrapper friend who saved it from the dump. It was $5, so can't complain too much. From the looks of it, this bike was lightly used and left outside a fair amount.

I don't think the cables need anything more than a good lubing, but there's a chance the RDER is shot.
I need to get off my butt and check all this stuff today! There's a chance the RDER is bent, it has fallen on it's side, so I'll check.

alcjphil

It is more likely that the cables are badly in need of attention. Bikes that are left outside a great deal are notorious for rusty cables

Wilfred Laurier

Unless you changed the cable when you got the bike, your assumption that it is the derailleur and not the cable is not a sound one. Cables are a wear item and you can generally expect to be able to use dozens of cables over the life of a derailleur.

caloso

Always check (and if necessary, replace) the cables first.

Bill Kapaun

Considering the history-
Before you invest any $ in this-
IF the bike spent time on its side and was rained on, expect to have a bad bearing cone or race in the hubs & BB.
Service the wheel bearings first to see if you have usable hubs. If things are badly pitted, things will come to a grind in the near future.
IF you want to proceed, servicing the BB is next for the same reason.
Unless you can fix this up with just your labor, some bearing balls, grease and a new cable & housing set and maybe a few other lube/solvents, it's probably going to be a worm hole.
It was a low end bike when new. They tend to have cheaper parts that aren't as well sealed and more prone to rust because of their metallurgy.
Sometimes "cheap" gets rather expensive.
Maybe a pic or 2 of the bike would allow us to make a more accurate assessment.

JTSpeedDemon

I checked the RDER cage with a straightedge, and it's straight as can be. I determined that the last turn of cable housing had excessive friction. So after a LOT of lubing, it works great again! It shifts much smoother and more consistently now.

Here's a pic of the bike:

alcjphil

And, what does this tell you? You assumed that the rear derailleur was worn out when really it was worn cables. Listen to the advice you get. Replacing those cables is probably long overdue

obrentharris 

Good job!
The bike cleaned up nicely from the first pictures you posted in your first thread to now.
Brent

JTSpeedDemon

Yup, sure did!

Yeah, I knew it was likely the cables, but I decided to throw it out there just in case I was blundering, and the RD springs have a little rust on them, so I was wondering. As far as replacing the cables, believe me, I would, but between my kart, this bike, and a few other projects, I don't have much money at all. Mowing season is picking up around here though, so that should change soon, and new cables are on the list for future purchases.

Bill Kapaun

I'd suggest finding a safe place and giving the brakes a few panic stops so you know what to expect.
If a cable breaks, better to have it where you are in control.

The brake calipers on these tend to be very flexy. Add a wheel that has a wobble.
Brakes have to be backed off so they don't rub and the lever often hits the bar before you get adequate braking.
I bought my first wheel truing stand because of bikes like these. You simply had to have the wheels true so you didn't waste any lever travel.
Steel wheels make things worse for braking friction.

dabac

You need to think about how these things work.
The overwhelming majority of rear derailers are what’s called ”high-normal”. Meaning that there’s a spring that will try to keep the derailer at the highest gear/smallest sprocket and the shifter cable that pulls it towards thelower gears/ bigger sprockets.
If you disconnect or slacken the cable, the derailer should move back to the highest gear/smallest sprocket by itself.
If you’re getting excess cable poking out through the shifter, then either the derailer return spring isn’t pulling as it should or the cable isn’t sliding as it should. Or the high limit screw is set VERY wrong.
So tensioning the shifter cable is the WRONG move.
To get to the smallest sprocket you need that slack you see by the shifter to transfer to the derailer end.
Try putting the shifter in the position for the highest gear and see what happens if you help the derailer along a little by hand.
If that makes it go into gear you most likely have too much cable friction. Sometimes though, a derailer will basically tire. I had an old Shimano 600 that required pretty much pristine cabling to work as it should.

dedhed

https://www.walmart.com/ip/Bell-Pit-...Black/49706850

JTSpeedDemon

Already fixed, but thanks for the input!

That one says it's for index shifters. I'd rather take my bike to the local bike shop to make sure I get the right parts.

Brakes work great! Only need about 1/2 the pull to get full braking power. I can stop on a dime.

dedhed

Doesn't matter, just compressionless shift housing. Will give you quicker less sloppy shifting on friction

tFUnK

"Do I need to put the shifter in the highest gear position and tighten the cable?"

Yes