Derailleur advice, retrofit old bike to new gear, Test Ride

[Indyjps]

I'm considering stepping up my game on my old mtn bk. Currently 6 x 3 shimano derailleurs, pretty sure the rear is tweaked when I got hit by a car on the bike years ago. Intended use is casual trail riding, light jumping and street duty.

I'd like to go to new rear derailleur, and single front gear.
Considering staying with shimano.

Will tourney perform well? Its offered in 6 speed which will work with my existing spin on freewheel.

Is there a noticeable difference moving up to acera, alivio. I see these for 7 or 9 gear.

I'm used to click shift, don't know anything about trigger shift, should I go trigger shift?

Do I need to change to 7 gear rear?

Really just looking to set this up better and buy the parts once, get it reliable again, love the bike, fit and feel, but it's high maintenance and sits frequently waiting on tune ups.

http://www.ratrodbikes.com/forum/index.php?threads/nashbar-return-from-dead.99684/#post-1000391

 

[us56456712]

If you like the bike I would get a new rear wheel dished for a 9 speed. You can go with 10 or 11 but I prefer 9 speed. My set up has a medium cage derailleur, which cost about $100. I don't remember what is is without looking. I did this summer before last and at that time the smallest offset narrow wide chain ring was 28 tooth. I needed an offset to keep the chain line when I converted from 3 chain wheels. Some people need a rear derailleur that is designed for a single chain wheel to keep the chain on, even with a narrow wide. Some also use a chain tensioner but I use neither and have no problems keeping on a chain. A derailleur for a single speed costs more. I kept throwing chains on single track before I went with the narrow wide. It is a compromise and I can keep up on the faster sections and it is low enough so I can climb most hills. It has a Sunrace 11 x 36 free hub cassette but I recently bought a new Sunrace cluster that is 11 x 40. I also have 2 bikes set up with 20 tooth chain wheels. It takes some filing for the chain to clear the bolts, but they work well. I am in the process of converting one bike to a 20 tooth titanium chain wheel and a 11 x 40 cassette. Cross chaining with this setup will probably destroy the rear derailleur so I am replacing the large chain wheel with a bash guard. I don't need the large chain wheel and never used it on our trails. I considered removing it and change it for a bash guard last year but it shifted so nice I just left it. I think a 9 x 2 is all you need. I'lll have to post on this setup when I finish and ride it. It might be too low with a gear inch of 13. Slower than walking. I might have balance issue?

My Giant ATX rigid from the 90s with 20 tooth x a 7 speed screw on cassette with a 34 low gear. works awesome. No need for a new rear wheel. It's got 2.35 tires to help absorb shock. I love this bike.

 

[squirreldh]

Looking at the frame it should be able to accept some more modern parts. It has a derailleur hanger which is a plus!

If you do upgrade to more speeds, you will end up swapping a lot of parts, but can make it perform better. Being that it is a 6 speed on the rear wheel, I imagine it has a thread on freewheel. You can get 7 and 8 speed freewheels that are shimano SIS index compatible, but may need to play with axle spacing and wheel dish on your current wheel to get it to fit properly. Finding a wheel made for 7 or 8 speed freewheels would be easier as its more plug and play than customizing your current wheel. Or, since you are upgrading and modernizing, you might as well get a wheel that has a freehub as opposed to a freewheel, this will allow you to go up to 9, 10, or even 11 speed on your rear wheel, plus will perform better shifting wise, and be stronger, the freewheel style wheels tend to bend and break axles if abused as the bearing is quite a ways inboard away from the frame on that style.

Either way you go, you will need to get the corresponding shifters, cranks/chainrings, cassette/freewheel and chain. You can get the 7 and 8 speed to play well with your current crank/ring setup, but 9, 10, and 11 will need a crank/ring setup designed for each specific drivetrain.

Trigger shifters are what I think you are referring to as "click" shifters, they have a thumb and index finger lever for shifting up and down through the gear range, and are indexed for each gear. Obviously you need a 7 speed shifter for a 7 speed cassette, and 9 on 9, etc...

Your current rear derailleur will work for 7 and 8 speed, and maybe 9, but not 10 or 11 as the pull ratio changed. Shimano ran a 2:1 pull ratio on their shifters/derailleurs through Mega 9, but changed when they went to 10 so those components cannot be interchanged.

If you want to do a 1x drivetrain, meaning one ring up front, and multiple in the rear, 1x7, 1x9, 1x11, etc... you will either need to use some sort of chain retention system similar to what DH guys use, or a more minimal one that is just an upper guide without the lower tensioner, or go with the more modern 10 and 11 speed derailleurs that use a "Clutch" which is basically a tensioning system inside the rear derailleur that helps prevent chain-slap, and a Narrow-Wide chainring in the front to prevent the chain from dropping off of the chainring.

I hope I haven't confused you too much....

 

[us56456712]

I have bent several axles on old mountain bikes with quick release and screw on freewheels. I have saved spares from bikes I have stripped but hate changing them. If you don't ride fast over rough ground it should be OK with the old screw on cassette but the new ones are superior. But I have stripped the guts out of a bran new free hub cassette. It must have been defective as it only lasted a few weeks and others ride a lot harder and are stronger than I am. I have also broken two frames riding but those were also defective. I use my converted ATX for C group rides (VS A and B level) and for gravel. Works great but the last time I used it I broke a chain so I have to fix that. Mountain biking is hard on rider and equipment.

 

[SILVERKINGPC]

Like squirld says above, I would get a "freehub" wheel for a 7 or 8 spd. and maybe some ebay trigger shifters to match(shimano LX). With a cassette-style wheel and hub setup, you can easily find cheap "trigger" shifters(7-8spd) of various quality, as well as new cassettes and new chains cheaply and abundantly. No problem running one ring up front. Once you venture past 8spd, the cog spacing and chain widths narrows as the gears are added, so new shifters are also required.
As far as breaking stuff, welcome to the rear freehub blowout club. In order to stop this completely, you have to pay upwards of $250-$350 for a rear hub only that can hold up to the forces exerted on the drive pawls inside. Most rear hubs are poorly designed and blow up even when new. My experience dishing out years of MTB abuse with no ratchet or axle failures is Hope Pro, Industry Nine, Chris King, and perhaps DTSwiss...... That said, you get what you pay for. skpd

 

[Indyjps]

Great feedback. I am partial to the current araya rims. And love the high flange shimano hubs.
So I need to balance performance with nostalgia since I've owned this bike for 25 years. I get it that this rigid old bike won't be a trail killer, I have a newer Trek I could ride for that.

I could replace the rear to a new hub.

Is a 7 speed spin on freewheel an option, or can I use a 7 speed derailleur on my 6 speed freewheel and limit it.

I don't have to eliminate the front derailleur, I was looking to simplify the bike, let me read up in DH tensioners

 

[SILVERKINGPC]

Is a 7 speed spin on freewheel an option, or can I use a 7 speed derailleur on my 6 speed freewheel and limit it.

Yes...Both options will work with the 7-spd shifter. I believe the spacing and chain width is the same. You don't need a chain tensioner if you only run one front ring either. If you have a strong derailleur cage spring,(most are)it does the same thing for the most part: just make the chain shorter for more tension on the cage. If you aren't beating it to death, most low-end rear cassette hubs should hold up ok..

 

[squirreldh]

You don't need a chain tensioner if you only run one front ring either.

Riding offroad without some sort of guide or tensioner to keep your chain on the chainring is a sure way to injure yourself. I have experienced chain drop just rolling around town on a setup like that, would not recommend going offroad with that setup.

I know some, myself included, have used the front derailleur as a guide. Use the limit screws to hold it in place over the ring, guiding your chain onto the ring while pedalling forward. Not the best tool for the job but will work. MRP also make a simple upper chainguide, minus the lower tensioner, for use on 1x drivetrains. I used one for a few years on my Kona when I decided to add gears instead of running singlespeed. It mounts between the frame and bottom bracket and is basically a solid nylon impregnated plastic derailleur cage that guides the chain onto the ring and prevents it from derailing. They also have versions that mount to the seat tube. If you go modern enough to go with a clutch equipped rear derailleur you do not need a guide on the front ring.

MRP 1x chain guide:

 

[horsefarmer]

Finally a use for a front derailleur!

 

[SILVERKINGPC]

Yea, I get the chain-guide thingy, but I have never had a problem with my chain coming off while riding rough singletrack littered with rocks and babyheads except on very rare occasion. I have never injured myself either because of a chain dropping onto my bb shell. Most people are not jumping off of cliffs or houses or boulders with their bikes, and generally won't need a chain-guide.
The derailleur will take the slack out of the drive system for the most all average riding conditions similar to what Indyjps describes he will be doing with the bike. On the other hand, If you are a downhiller or "free-rider", you may consider mounting one for sure. For me, they are just another thing to mess with, they cause drag, and they make more noise..

 

[Bicycle808]

Some thoughts:
-before you select a new rear hub (or decide to keep the original one), do yourself a favor and catch-up on the current specs. What is the OLD spacing of the current hub? Does it match the dropout spacing of the frame? Are you willing to respace the rear-end to accommodate a slightly more modern hub, if need-be? If the rear-end has been tweaked, you're going to need to re-align the stays anyway. If you need to do that anyway, it might make sense to re-space if need be.
-speaking of the rear-end damage, you're going to want to check that your derailer hanger is PERFECT. Not "pretty good," not "decent," not "good enough for RRB"-- perfect. Unless you want to run it friction. If you intend to run an indexed system, you'll need the danged hanger to be straight. If you skip this step, and try to index, and it ghosts or otherwise misfires, the reason will be the hanger is tweaked.
-freewheel hubs are, as others mentioned, more prone to bent axles. If you're gonna ride trails, i'd definitely consider running a cassette hub. If you're bike is the bike i think it is, it is spaced 126mm with a 126mm freewheel rear hub.
-Also, if this is the bike I think it is, it came with XT components, hence the name Terra XT. If you're honestly thinking of ditching Deerhead XT for contemporary Tourney, i don't know if I can help you. But, you can also sell me the full XT group for cheap. That'd be fine.
-FYI- if your rear derailer is a Deerhead marked RD-M700, it's a friction design. If it's marked RD-M730, it's already ready to index already. So, that might be a factor if you're just trying to upgrade to indexed.
-Soapbox time: 1x1 offroad drivetrains suck, unless you're riding downhill or something. In which case, you'd probably have a real guide and an ISCG tab on the BB and/or a wide/narrow chain and front ring. You can run the hokey little dead-derailer-style guide, i guess.... but why remove a functioning derailer to replace it with a dead derailer that poorly functions as a chain-tender? Wide/narrow chains are awesome and they work, and that's all you'd need for XC/ general trail use. But wide/narrow chains are expensive, and they require the use of a wide/narrow front sprocket, which are also expensive. You'd also want to run a shortcage RD, but make sure you pick one that can handle your largest rear cog. Those ain't cheap, neither. So, in an effort to "simplify," the 1-by crowd spends extra money to get less range and they often end up running as many doo-dads anyway. I'm pretty much of the philosophy that singlespeed is good, and 3-by is good.... and modern 2-by is good, with the current cassette offerings.... but 1-by is the worst of both worlds. Of course, yeah yeah yeah, ppl can do whatever they like with their own bike, but this is an "advice" thread. You can run 1-by if you like, but if you do:
-you won't save money (you'll spend more!)
-you won't reduce the amount of crap bolted to your bike (unless you spring for narrow-wide)
-you will reduce your range significantly
-you will achieve state-of-the-art coolness, according to 2008 trends

Shimano XT, however, especially from the 80s, is a classic group that won't ever go out of style.... like i said, if you're selling it, i'm buying it.

 

[SILVERKINGPC]

Great reply by B808. Good advice for sure in regards to his response.
I am of the same philosophy for the most part, partly because I know what works and what breaks after thousands of miles, and mostly laugh at my friends spinning like crazed squirrels in fast sections of dirt as they are single-ringer band-wagoners. Not me, I still ride a 26-er, no dropper and three rings up front. Like B808 says, whatever flips your switch!
I would agree also that all those that jump on trendy bandwagons aren't necessarily getting something "better" in the end. Just different.
33.3+++ wheels, and soon-to-be cooler 15-cog/dished out wheels with single ring setups where the biggest cog is as large as the moon is soon to be on deck.
Oh geez.

 

[Duchess]

Bikes last a long time and are (usually) easily fixable and reconfigurable, so manufacturers need to come up with something to sell people new bikes, hence the proliferation of expensive bikes made from less durable, more difficult to fix, and catastrophically failure-prone materials where the fear of latter brings some customers to buy a new bike within a few years or so all marketed under the guise of lower weight nearly irrelevant for anyone who's not a sponsored rider (hilariously, I recently saw a ridiculous product being sold to add weight to light bikes for training purposes), more finicky components on ordinary bikes to drive work for LBS mechanics and/or annoy customers to trade in for new prematurely, trends that aren't actual improvements, and the, uh, cycling between recommendations, like wider tires to super skinny and back.

I second making sure the derailer hanger is perfect before anything else and, since you're not going for the latest thing, you might want to consider used parts for cheap. A good quality used rear derailer, if you need one, should be cheap for a 6-7-8 speed.

One thing that I'm curious about in Bicycle808's informative post is the real world difference in a friction or index rear derailer. As far as I can figure, the derailer shouldn't care how the cable is pulled, it just moves as much as the shifter moves it whether that be by friction or indexing, it doesn't know the difference. I'm not disputing the statement, just curious what the actual difference would be between the two derailer types (if there is any besides marketing distinction).

 

[1oldbikelover]

If you like the bike I would get a new rear wheel dished for a 9 speed. You can go with 10 or 11 but I prefer 9 speed. My set up has a medium cage derailleur, which cost about $100. I don't remember what is is without looking. I did this summer before last and at that time the smallest offset narrow wide chain ring was 28 tooth. I needed an offset to keep the chain line when I converted from 3 chain wheels. Some people need a rear derailleur that is designed for a single chain wheel to keep the chain on, even with a narrow wide. Some also use a chain tensioner but I use neither and have no problems keeping on a chain. A derailleur for a single speed costs more. I kept throwing chains on single track before I went with the narrow wide. It is a compromise and I can keep up on the faster sections and it is low enough so I can climb most hills. It has a Sunrace 11 x 36 free hub cassette but I recently bought a new Sunrace cluster that is 11 x 40. I also have 2 bikes set up with 20 tooth chain wheels. It takes some filing for the chain to clear the bolts, but they work well. I am in the process of converting one bike to a 20 tooth titanium chain wheel and a 11 x 40 cassette. Cross chaining with this setup will probably destroy the rear derailleur so I am replacing the large chain wheel with a bash guard. I don't need the large chain wheel and never used it on our trails. I considered removing it and change it for a bash guard last year but it shifted so nice I just left it. I think a 9 x 2 is all you need. I'lll have to post on this setup when I finish and ride it. It might be too low with a gear inch of 13. Slower than walking. I might have balance issue?

My Giant ATX rigid from the 90s with 20 tooth x a 7 speed screw on cassette with a 34 low gear. works awesome. No need for a new rear wheel. It's got 2.35 tires to help absorb shock. I love this bike.
View attachment 49526

Wasn't aware a derailleur for a single speed cost more! I don't think you need a derailleur for a single speed. One crank ring...one rear cog.....single speed

 

[Bicycle808]

Wasn't aware a derailleur for a single speed cost more! I don't think you need a derailleur for a single speed. One crank ring...one rear cog.....single speed

Singlespeed can absolutely be cheap, depending on how you do it. I'm a huge fan of singlespeed, both on- and off-road. No need for derailers but, unless you have horizontal dropouts or track-ends, you will need something to maintain tension (millions of options) but we're not talking about singlespeeds.

Now, a "1-by" would be a single-ring up front and 5, 6, 7, 8, 9, 10, or 11 in the rear. You can definitely do that cheap, too... but if you ride singletrack on a set-up without a plan to retain the chain, you're gonna drop chain a lot. And, the various gizmos that help retain the chain can be expensive, or you can just use a front derailer but once you got a front derailer on there, why not run a cable to it and use it as a derailer?

 

[Bicycle808]

One thing that I'm curious about in Bicycle808's informative post is the real world difference in a friction or index rear derailer. As far as I can figure, the derailer shouldn't care how the cable is pulled, it just moves as much as the shifter moves it whether that be by friction or indexing, it doesn't know the difference. I'm not disputing the statement, just curious what the actual difference would be between the two derailer types (if there is any besides marketing distinction).

The difference between various indexing derailers will be the leverage ratio, meaning how much cable is pulled and how that translates to how far in- or outboard the pulleys move. For a zillion years, shimano had a roughly 1.7:1 ratio for their indexed derailers and shifters, and folks typically refer to this as 2:1. But, it's not. Further, when they went to the Dyna-Sys 10 speed for mtbs, they changed the ratio to 1.2:1. But, weirdly enough, Shimano road 10 speed is still 1.7:1. TBH, i haven't a clue about the Shimano 11 speed ratios, but i think it's 1.2:1 for both road and mountain. One day, i'll get around to googling it.

So, BITD, Shimano set-ups basically worked where if the shifter matched the rear cluster, and the chain was narrow enough, any index-compat shimano rear derailer would work. Dyna-Sys ruined that. And, with different manufacturers, the ratios were ALL different, so you kinda needed to run the same brand shifter, rear derailer, and cluster... but all sorts of frankenstein techniques exist to get around that, like alt cable routing, "chips" at the cable anchor, products like j-tek's shiftmate, and trial-and error that revealed that some combos might kinda work when they shouldn't. But, the easiest way to rock it is by using a shifter that matches the rear cluster in both number of speeds and spacing between cogs (spacing varies among the manufacturers) and that the shifter matches the actuation ratio of the derailer. This is hard to do b/c all of the manufacturers got flakey. For instance, SRAM's "1:1" (which is actually 1:1) is different than their "Exact Actuation," which is different from their "X-Actuation." Stupid.

So, getting back to shimano, for the sake of simplicity.... let's say you have an XT rear derailer that is designed around indexing for 6 through 9 speeds. If you hook that up to a shifter that pulls 1mm of cable per click, it will move the pulley 1.7mm per click. If you hook that same shifter up to an XT rear derailer for Dyna-Sys 10-speed, that same "click" that pulls 1mm of cable will only move the pulley 1.2mm. See how that might make compatibility a problem?

Now, getting back to the actual question, about why it would make a difference if the derailer was designed for indexing or not? With all of these very exact ratios in place just for indexing, what are the chances that they made a derailer designed for friction that will have the perfect pull ratio? When they designed those old derailers, they s'posedly shot for roughly 2:1 ratio, but precise actuation wasn't even a design concern at the time?

All of this garbage is really frustrating, and i hate it. I've wanted to boycott entirely and rock friction-only, but i simply don't have the force of will. Indexing is just cool. Thankfully, there's enough shimano stuff with the 1.7:1 ratio out there. Tons of used, plenty of NOS, and the current-production stuff is still 1.7:1 if it's 9 or fewer speeds, and road 10speed....and, AFAIK, the stuff put out by MicroShift and SunRace is the same 1.7:1 ratio as Shimano---like i said earlier, usually referred to as "2:1" even though it's not... But, I REFUSE to buy anything Dyna-Sys, and i stay away from SRAM, Campy, and Suntour, mostly to simplify my parts box.

Now, I know this is RRB, and the prevailing philosophy is "bolt it on there, say a prayer, and if it don't work right, smack it with a mallet" but, when I give advice on here, I try to keep folks away from problems like ghost-shifting, skipped cogs, or total trainwreck failures.

Here's some further reading on the topic. Sheldon Brown is my top role model, but the info on the Art's Cyclery site is more up-to-date and thorough.

http://blog.artscyclery.com/science...ce-behind-the-magic-drivetrain-compatibility/

https://www.sheldonbrown.com/drivetrain-mixing.shtml

HTH.
-Rob

 

[Duchess]

So, the derailer varies in how it reacts to cable pull distance. I figured they were all 1:1 and differences in indexing requirements between types were all determined by the shifter itself and problems with mixing brands was down to manufacturer's proprietary sprocket spacing. Good to know—I've been lucky to have never encountered a problem. Thanks!

 

[Indyjps]

This is great stuff, more more than I've ever considered.

Little story here about this old nashbar, I was always a BMX rider and racer.
I bought this from a local rider who always had the nice stuff, he'd also been a bmx racer that got into trail riding. I rode the heck out of it on motorcycle trails.
But one of the main reasons I got it, was a girlfriend who lived in the country, who's parents went to bed early. I needed gears to make that ride. So I've logged many miles on this thing on country roads in the middle of the night.

Story aside, I wanna get it reliable. I did get hit by a car on it and that's why it got parked. I as able to fix the rear rim, I do need to tear it down and check frame alignment, that could be the main issue I'm having.

It's currently set up as friction shift, which I kinda like, it's got it's limitations on trails.

The adjustment just drifts. I dial it in, and a couple rides later it gets a mind of its own. I was mainly considering swapping to new components to get away from that and get it reliable.

Can I take this derailleur and go to click shift? Will it index correctly? I don't mind recabling it all, checking frame alignment, rebuilding the freewheel. Whatever it takes. I just want it to work again.

 

[squirreldh]

-Also, if this is the bike I think it is, it came with XT components, hence the name Terra XT. If you're honestly thinking of ditching Deerhead XT for contemporary Tourney, i don't know if I can help you. But, you can also sell me the full XT group for cheap. That'd be fine.

Shimano XT, however, especially from the 80s, is a classic group that won't ever go out of style.... like i said, if you're selling it, i'm buying it.

This is awesome. Something I hadnt even considered! Hard to see from the pics as they are from the non drive side, but if its shimano XT with the deerhead then either keep it OG, restore it and keep it running as is, or sell the whole grouppo to Bicycle808 and fund your rebuild! That is a cool group of parts, and I love the high flange hubs on those wheels as well. It all depends on what you want to do with it, your bike, your build, and as you have seen already, there are probably thousands of different ways to do it!


Sent from my SM-G550T1 using Tapatalk

 

[Duchess]

If it's drifting out of adjustment, the cable may also be the culprit. Anything that can cause too much and variable friction in the system—worn or rusted cable or too tight a bend(s) in the housing. Definitely get the alignment checked first and if it's good, I'd redo the cable unless it's new and the bends are wide and supported (too much bend can have the housing flop around or cause additional bends). A common example of the latter would be too much slack going from the handlebar to the first braze-on cable stop. If there's too much slack there, the housing would have to make a small secondary bend something like an S curve to get into the cable stop. If it's possible on your bike to cross the shift cables so that they use the cable stop on the opposite side of the frame, you can get a wider bend and eliminate the S curve, especially when the bars are turned. The shift cables would have to cross each other in a X pattern under the tube (so, you need cable stops that are more to the underside of the down tube so the cables don't rub the tube itself), but the contact there is insignificant and certainly less than the S bend (which also varies depending on the handlebar angle). Actually, an indicator of this would be if the shifting worsens when it's shifted with the handlebar turned in the opposite direction as that would increase the secondary bend where the housing goes into the stops. The curve at the back from the chainstay to the RD can also be a problem, but less so as it's better supported and doesn't change nearly as much during operation.