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  1. #1
    Seņor Member
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    Sorry if I'm pulling out the ol' stick to beat on a dead horse.

    I've done my research (searched the forums, internet, all that) and I think this will work, but I'd like to hear everyone's opinion on whether I've missed anything.

    I have a 1983 Miyata touring bike. It has a 5-speed Suntour freewheel and friction shifters on the downtube. I'd like to upgrade to indexed shifting. I don't want to have to resize the frame and redish the wheel, and I want to keep the shifters on the downtube. Here's what I plan:

    The spacing is 120mm, so I'll get an Ultra 6 freewheel from the Bay, which will fit in the dropouts. According to Sheldon Brown, the sprocket spacing is 5mm on an Ultra 6, which is the same as a Shimano 7-speed freewheel. Then I would get Shimano SIS downtube shifters (the ones where the rear shifter is indexed and the front is friction), a Shimano SIS derailleur, and a new narrower chain to fit the new freewheel. As long as the derailleur has at least six speeds, it shouldn't matter too much what I get as long as it's SIS, because I can just set the adjustment to not go past the last cog on the freewheel - the important thing is that the shifters match the derailleur.

    So will this work? Is there anything obvious (or maybe not so obvious) that I've forgotten? How are the shifting characteristics of an Ultra 6 freewheel?

    Thanks!

  2. #2
    Senior Member sydney's Avatar
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    Quote Originally Posted by BryE
    Sorry if I'm pulling out the ol' stick to beat on a dead horse.

    I've done my research (searched the forums, internet, all that) and I think this will work, but I'd like to hear everyone's opinion on whether I've missed anything.

    I have a 1983 Miyata touring bike. It has a 5-speed Suntour freewheel and friction shifters on the downtube. I'd like to upgrade to indexed shifting. I don't want to have to resize the frame and redish the wheel, and I want to keep the shifters on the downtube. Here's what I plan:

    The spacing is 120mm, so I'll get an Ultra 6 freewheel from the Bay, which will fit in the dropouts. According to Sheldon Brown, the sprocket spacing is 5mm on an Ultra 6, which is the same as a Shimano 7-speed freewheel. Then I would get Shimano SIS downtube shifters (the ones where the rear shifter is indexed and the front is friction), a Shimano SIS derailleur, and a new narrower chain to fit the new freewheel. As long as the derailleur has at least six speeds, it shouldn't matter too much what I get as long as it's SIS, because I can just set the adjustment to not go past the last cog on the freewheel - the important thing is that the shifters match the derailleur.

    So will this work? Is there anything obvious (or maybe not so obvious) that I've forgotten? How are the shifting characteristics of an Ultra 6 freewheel?

    Thanks!
    Actually, 7 speed shimano is 4.8mm. So the cog spacing is close enough it will probably work,but not good enough for some. Derailers don't have 'speeeds', but an sis will work but it it's pre 9 speed DA than you need pre 9 speed DA shifters to go with it.A sram 8 speed chain will work.

  3. #3
    Senior Member juicemouse's Avatar
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    Quote Originally Posted by sydney
    Actually, 7 speed shimano is 4.8mm. So the cog spacing is close enough it will probably work,but not good enough for some. Derailers don't have 'speeeds', but an sis will work but it it's pre 9 speed DA than you need pre 9 speed DA shifters to go with it.A sram 8 speed chain will work.

    Oooh, I get to call sydney out... This should be fun.

    8s Shimano is 4.8mm. 7s is 5.0mm. Suntour Ultra 6 is 5.0mm also, but most other 6s is 5.3mm, so watch out. If you're reading Sheldon, you're well on your way to a good setup.
    It is my belief that every person in this world has something to teach, and everything to learn.

    In memory of Jim Price (aka. sydney) ...

  4. #4
    Senior Member sydney's Avatar
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    Quote Originally Posted by juicemouse
    Oooh, I get to call sydney out... This should be fun.

    8s Shimano is 4.8mm. 7s is 5.0mm. Suntour Ultra 6 is 5.0mm also, but most other 6s is 5.3mm,
    See what that afternoon carpet smokin will do will do to an already fried brain? Old sydney did have it right the last bizillion times he said it. Trust him...

  5. #5
    Gone, but not forgotten Sheldon Brown's Avatar
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    Quote Originally Posted by BryE
    Sorry if I'm pulling out the ol' stick to beat on a dead horse.

    I've done my research (searched the forums, internet, all that) and I think this will work, but I'd like to hear everyone's opinion on whether I've missed anything.

    I have a 1983 Miyata touring bike. It has a 5-speed Suntour freewheel and friction shifters on the downtube. I'd like to upgrade to indexed shifting. I don't want to have to resize the frame and redish the wheel, and I want to keep the shifters on the downtube. Here's what I plan:

    The spacing is 120mm, so I'll get an Ultra 6 freewheel from the Bay, which will fit in the dropouts. According to Sheldon Brown, the sprocket spacing is 5mm on an Ultra 6, which is the same as a Shimano 7-speed freewheel. Then I would get Shimano SIS downtube shifters (the ones where the rear shifter is indexed and the front is friction), a Shimano SIS derailleur, and a new narrower chain to fit the new freewheel. As long as the derailleur has at least six speeds, it shouldn't matter too much what I get as long as it's SIS, because I can just set the adjustment to not go past the last cog on the freewheel - the important thing is that the shifters match the derailleur.

    So will this work? Is there anything obvious (or maybe not so obvious) that I've forgotten? How are the shifting characteristics of an Ultra 6 freewheel?
    The Ultra 6 freewheels have more or less the desired spacing, but it's an oddball system, and they don't shift nearly as well as modern stuff does.

    I would very strongly recommend that you go for a 7-speed freewheel. The Shimano ones are a fantastic bargain, and they're way better than those old Sun Tours. See: http://harriscyclery.com/freewheels

    On a high quality steel frame like yours, re-spacing to 126 or even 130 mm is a trivial matter, and it is silly to let fear of this minor modification prevent you from using better, cheaper parts.

    See: http://sheldonbrown.com/frame-spacing.

    I'd recommend a set of Sora 7-speed STIs. The controls really belong on the handlebars, not the down tube, especially on a touring bike. Also, the modern STIs would considerably improve the braking, and the Sora stuff is quite inexpensive. See: http://harriscyclery.com/shifters

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  6. #6
    Senior Member DannoXYZ's Avatar
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    The only reason I'd use an Ultra-6 would be if I already had it or someone gave it to me for free along with the shifters and derailleur. The cogs on the Ultra-6 is also slightly thicker than the Shimano. You should measure the thickness of the cog+spacer to get the center-to-center spacing between the gears. Also the Ultra-6 does not have identical C-C spacing between all the cogs, most likely due to linear pull on the levers, whereas the Shimano levers have a non-linear pull to generate constant spacing between gears.

    Otherwise, if you're going to be paying for these parts, you might as well get the 7-speed stuff. I used to do this kind of mix & match 15 years ago and it can be made to work. The outer threaded cogs may need to be ground down to reduce its width to Shimano 7-speed spacing. The profile of the Suntour teeth also isn't as optimum as the twisted teeth on the Shimano. You can make it shift better by grinding the bevel on the corners a little more so that outside edges of the teeth are narrower, more similar to the Shimano. Grind the inside and outside corners on a diagonal so that the outer edge of the teeth narrow, almost sharp and angled like the twisted teeth on the Shimano cogs.

    Also get the Shimano chain, not that crappy replacement Sachs stuff that a lot of people use. The thin beveled edges of the outer links slide over the gears much better. One test I like to do is slowly turn the pedal by hand while shifting and measure the number of teeth that the chain rides on top of before it drops down into the next gear. Going down to smaller cogs is easy and both Shimano and Suntour are about even in stock trim. But going from smaller cogs to larger ones has the Shimano outperforming the Suntour 2:1. However, if you modify the Suntour cogs to match the Shimano's twist and use the Shimano chain, it will perform just like the Shimano stuff.

    As for the axle-width, you want minimal dish on the wheel and may need to juggle spacers to get optimum spacing in these areas:

    1. freewheel to spokes
    2. freewheel to drop-out.

    To get mimimum dish, I would spin most hubs on a lathe and move the freewheel about 3-4mm closer to the spokes (get rid of those plastic spoke-guards). Then arrange spacers on the right side of the axle to place the chain less than 2mm away from the drop-out when in the big-ring/small-cog combination. About 1.5mm is good. Then add spacers to the left side of the axle to bring it up to 126mm. Then lace up the wheel or re-center as necessary. You can get beveled lock-nuts for the axle that makes it easier to slide the wider hub up into the narrower drop-outs.
    Last edited by DannoXYZ; 08-04-05 at 07:00 PM.

  7. #7
    Senior Member sydney's Avatar
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    Quote Originally Posted by DannoXYZ

    Also get the Shimano chain, not that crappy replacement Sachs stuff that a lot of people use.
    Sydney uses both Shimano and Sram chains on about every type of cog and can't tell the difference. The Shiamno chain can be made less crappy by using a sram or other suitable link depending on the chain wddth being used.

  8. #8
    Seņor Member
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    Quote Originally Posted by DannoXYZ
    Otherwise, if you're going to be paying for these parts, you might as well get the 7-speed stuff.
    Quote Originally Posted by Sheldon Brown
    The Ultra 6 freewheels have more or less the desired spacing, but it's an oddball system, and they don't shift nearly as well as modern stuff does.

    I would very strongly recommend that you go for a 7-speed freewheel. The Shimano ones are a fantastic bargain, and they're way better than those old Sun Tours. See: http://harriscyclery.com/freewheels

    On a high quality steel frame like yours, re-spacing to 126 or even 130 mm is a trivial matter, and it is silly to let fear of this minor modification prevent you from using better, cheaper parts.

    You know, that's excellent advice. I thought about respacing the frame and I read what Sheldon had to say about it (fantastic site, BTW - thanks!), but I have a problem - I don't have the tools or the experience needed for realigning the fork ends or for redishing the wheel. I've rebuilt bikes before, and I pretty much understand brakes, derailleurs, shifters, etc, but I don't work in a shop, and I've never needed to work on spokes before. Maybe the LBS would do it for me, but I prefer not to pay if I don't have to (I'm pretty cheap). If you guys can point me to some good sources for information, I'll spend some time thinking about it. I'm not at all afraid of doing the work myself, but I love this frame and I don't want to damage it, either. I'm not planning on doing anything to the bike until late in the fall anyway, 'cause I'll be too busy riding it to do any significant work on it.

    I work with a guy who used to be a bike mechanic - maybe he can give me some tips or lend me tools. And in the end, I think it would probably be cheaper to go with the respacing and 7-speed parts, and it sounds like the bike would be more enjoyable.

    Thanks for the advice, you've given me something to consider. If you anything else to add, I'd sure like to hear what you have to say.

    Thanks!

  9. #9
    Senior Member DannoXYZ's Avatar
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    "but I have a problem - I don't have the tools or the experience needed for realigning the fork ends or for redishing the wheel. I've rebuilt bikes before, and I pretty much understand brakes, derailleurs, shifters, etc, but I don't work in a shop, and I've never needed to work on spokes before."

    Pick up a copy of Jobst Brandt's "The Wheel Book", it's pretty simple to true the wheels. Basically it's an outside-in suspension bridge and the rims are "hanging" by the spokes. You tight/loosen the spokes to move the rim left/right and up/down until it's perfectly round and centered.

    You can do frame-alignment yourself without special tools. The fork is easiest. You can make your own alignment tool by using a broom-stick that fits into the steerer-tube. Attach a 6" section of 2x4 to the other end of the broom-stick and draw a centerline through the middle of the 2x4 and broomstock. Stick it into the fork so the 2x4 is even across the fork-tips and measure distance to center-line with a ruler. both fork-blades should be space identically away from the center.

    The rear drop-outs can be aligned with a string. Wrap one end between the outside of the drop-out and the open QR and tighten the QR to hold it. Pull the string up and tight around the head-tube and back around to the other side. Loosen QT and wrap the other end of the string around that end, tighten QR. Take out a ruler and measure the distance between the string and seat-tube on either side. Bend teh rear-triangle towards one side by 1/2 the difference in the measurements you made.

    As for the wheels, you can use the brake-pads as a truing stand. Make sure the pads are perfectly centered on either side of the center mounting bolt. Then tighten the adjuster to narrow the pads and true until the rim can spin smoothly through the tighest clearance of 0.1mm. Then take the wheel off and flip it around and put it back in. A properly dished wheel will still be centered between the pads. If not, pull the wheel over by 1/2 the difference (your brake-caliper isn't centered if the wheel is centered one way, but not when flipped around).

    To true for roundness, take the tire off the rim and stretch a piece of tape across the seat-stays and fork. Place it about 0.5mm away from the rim and spin to check for roundness. Using the tape and brake-pads, you can get a wheel within 0.1mm of perfection easily.

  10. #10
    I drink your MILKSHAKE Raiyn's Avatar
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    Quote Originally Posted by DannoXYZ
    get the Shimano chain, not that crappy replacement Sachs stuff that a lot of people use.
    In my experience the SRAM chains are far more durable than any of the Shi*No's I've run over the years so I have no idea where you get off calling them "crappy"
    Quote Originally Posted by DannoXYZ
    "but I have a problem - I don't have the tools or the experience needed for realigning the fork ends or for redishing the wheel. I've rebuilt bikes before, and I pretty much understand brakes, derailleurs, shifters, etc, but I don't work in a shop, and I've never needed to work on spokes before."
    Try this next time.

  11. #11
    crusty old wrench
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    Brye,

    1st question: you've made it this far with friction; why unnecessarily complicate your classic rig? Friction is light, simple, nearly always works, and doesn't care what mix-n-match you have going on amongst the components in your drivetrain. Plus, it's the cheapest! I run these gorgeous little Simplex downtube levers on my Merckx with an 8spd Dura Ace hub, 9 spd XTR long cage rear derailleur,11-32 9 spd XTR cluster, 8 spd-era Dura Ace crank (53x39) and a Wippermann Connex chain. Light, simple, gobs of low end (I live in San Francisco), silent, and it works without hassle.

    I'm assuming the main goal of your proposed mods is to have more gears, right? (not just to have your bike start making clicking noises...). Sheldon's correct that there are still decent quality freewheels out there, in 7 and 8 spds, as well as close and wide ratio clusters. Sachs/SRAM makes a nice one, and some Shimano ones are OK, though the more recent Chinese ones are not as smooth and quiet as the previous Japanese ones.

    How about a modern rear wheel, i.e. box section rim and cassette hub with a home brew frame respacing? You could fashion a turnbuckle to expand the drop-outs incrementally, experimenting with how much past the 130mm or 135mm goal is (depending on what hub you get). I recommend going with a mountain oriented hub on a beefy rim: perfect for touring. Your steel frame can be flexed and cold set very nicely without damage (just don't pry it apart with your hands, though!), and the cassette hub is far more reliable than a frewheel hub spaced out to the 130 or 135mm needed for a 7-8 spd cluster due to the huge increase in bearing support of the axle.

    Historic note: cassette hubs came on the scene when engineers wanted ever greater numbers of cogs, pushing the overlocknut (the distance between the two outside faces of the locknut, which in turn corresponds to the same optimum measurement inbetween the the inside dropout faces) dimension ever wider. This left more and more unsupported axle due to the drive side bearing remaining inboard of the cluster. This led to increased flex at the axle and dropout (eventually causing failure) as well as decreased bearing life and hub race damage. The cassette hub corrects all of this by running the drive side bearing all the way out at the dropout.

    By going with a new, modern rear wheel and keeping friction, you can run your existing drivetrain components indefinitely, replacing it piece by piece as you wish. If the end goal is indexing, just replace each individual piece with that goal in mind.

    Chains: IMHO, Shimano chain are not worth the money. Sachs/SRAM are cheap and strong, and Wippermann Connex (stainless) are awesome. An old, wise man once told me: "Shimano wears out, Campagnolo wears in". Well put, and it precisely illustrates why Euro chains are superior to Japanese chains. The Shimanos shift and feel great for about 100 miles, then it's all over. I like to get more than one ride out of a chain...

    Shifter placement: if you like them on the downtube, leave them there! Plus, status quo is FREE.

    Hope this ramble helps...
    1 speed's all you need.

  12. #12
    Senior Member DannoXYZ's Avatar
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    "In my experience the SRAM chains are far more durable than any of the Shi*No's I've run over the years so I have no idea where you get off calling them "crappy"

    I'm not talking about durability, I'm talking about shifting-performance. Under ideal operating conditions with matching cassettes, derailleurs and shifters, both the Sachs and Shimano chain will perform as best as possible given the flexiblity of the chain and they'll shift from small to big cogs within 3-4 links. With identical performance and a better bang-for-the-buck value in durability, you may like the SRAM chain better, fine. I'm not talking about that, I'm talking about a test with quantitative numbers that you can replicate yourself and see that the Shimano HG chain works better when you've mismatched, never-designed-to-work together set of components like Shimano derailleurs with a Suntour cluster. The teeth on the Ultra clusters are FAT, they're also flat on the tips which causes a chain to ride on top of the teeth instead of sliding down cleaningly. Try using an Ultra cluster with Shimano derailleurs and spin the crank by hand slowly so you can count the links that pass between the point where the derailleur moves when you shift and when the chain falls down into the next larger cog. You'll see for yourself that the SRAM chain will ride on top of the Suntour cogs for about 4-6 teeth usually before engaging. The wider outer plates with sharper bevel on the Shimano chain allows it to shift within 3-4 links on the Ultra cluster, just like the Shimano cogs. I'm calling the performance of the SRAM chain relative to the Shimano chain on non-standard configurations "crappy", not its durability.

    BryE, I'm also wondering about your desire to go index as well. I was using 9-speed clusters for 3 years before Shimano came out with them by grinding down the spacers and welding a 11t cog onto the lockring. But that required using the DA shifters in friction mode only. It's certainly worked fine for me and I never lost a race because I mis-shifted. Crusty's got the right idea with the cassette as well, I wouldn't go beyond 7-speed and 126mm spacing with the freewheel. I've bent plenty of axles on 8-speed freewheels and 130mm hubs on my mountain bike.

  13. #13
    Seņor Member
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    Quote Originally Posted by DannoXYZ
    BryE, I'm also wondering about your desire to go index as well. I was using 9-speed clusters for 3 years before Shimano came out with them by grinding down the spacers and welding a 11t cog onto the lockring. But that required using the DA shifters in friction mode only. It's certainly worked fine for me and I never lost a race because I mis-shifted. Crusty's got the right idea with the cassette as well, I wouldn't go beyond 7-speed and 126mm spacing with the freewheel. I've bent plenty of axles on 8-speed freewheels and 130mm hubs on my mountain bike.
    When I started thinking about an upgrade for the trusty old steed, my primary goal was (and still is) to get more gears on the rear wheel. When I shift, I get some rattling noises from the back end and I have to spend a few seconds tweaking the shift lever to get rid of it. Not really a problem since I don't race, but it's annoying. I thought maybe upgrading to indexed shifting could take care of it, but now it appears to me that a better freewheel and chain would have a more noticable effect.

    When I said in my above post that I was very cheap, I wasn't kidding. I have some real issues with spending any money on myself at all after my employer want bankrupt a few months after the birth of our second child a few years ago *cue violin music *. So, while I recognize the value of your advice on a new wheel, I'm not willing to cough up the money for it. Believe me, I'd love to go with a cassette, but that upgrade, alas, is going to have to wait.

    What I'm thinking currently is I'll take the plunge and respace the frame to 126mm and get one of the Megarange Shimano 7-speed freewheels that Sheldon recommends and a new chain and keep my old derailleur and shifters. Then I can upgrade to indexed shifting later on if it seems worthwhile, and maybe even respace again to 130mm and get a new wheel with a cassette.


    Quote Originally Posted by crustyoldwrench
    Plus, status quo is FREE.
    Right on!

    So now, since I have your attention, I'm gonna hijack my own thread and ask a few questions about frame respacing. I read Sheldon's article about it, and I have no problems at all with bending the frame with a 2x4; I'm a duct tape and hammer kind of guy, and that's right up my alley. My problem is with the fork end alignment. Sheldon says there's no home mechanic tool for it besides a wrench and a good eye. Now, I'm OK on the wrench part, but the "good eye" has me worried. How about this instead: go to the local hardware store and buy a long, thin bolt and some big nuts to fit on it. Then tighten one of the nuts up at the head of the bolt and, while holding the bolt in the dropouts, thread the other nut up the bolt until it reaches the frame. Since the nuts are big and they are machined parts, you can assume that the faces of the nuts are perpendicular to the bolt, so you could use the nuts to measure whether the dropouts need to be adjusted with that big wrench. You could also use this technique to measure on the inside of the dropouts, and hence, I imagine you could get very close to having some nice, parallel dropouts. Does anyone see a problem with this method?

    And BTW, thank you all for your helpful comments. Even if I don't take your advice, I really do appreciate it.

  14. #14
    Spoked to Death phidauex's Avatar
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    Your method sounds good. I often use an old bolt on front hub to lock onto one of the dropouts so I can use the hub as a 'handle' for moving the dropout around to align them. Seems to work well.

    I think you'll be pleased at the shifting, even in friction mode. I found that 7 speed Uniglide in index mode shifted worse than 9 speed hyperglide in friction mode. Modern parts with actual shift ramps and shaped teeth really DO help, I was amazed at how well the 9 speed stuff shifted in friction mode.

    The only reason I'd go index is if you were moving the controls to the bars. If they are on the downtube, they might as well be friction.

    peace,
    sam

  15. #15
    Senior Member DannoXYZ's Avatar
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    "How about this instead: go to the local hardware store and buy a long, thin bolt and some big nuts to fit on it. Then tighten one of the nuts up at the head of the bolt and, while holding the bolt in the dropouts, thread the other nut up the bolt until it reaches the frame. Since the nuts are big and they are machined parts, you can assume that the faces of the nuts are perpendicular to the bolt, so you could use the nuts to measure whether the dropouts need to be adjusted with that big wrench. You could also use this technique to measure on the inside of the dropouts, and hence, I imagine you could get very close to having some nice, parallel dropouts. Does anyone see a problem with this method?"

    This will work fine for spreading or tightening the fork-tips together to get perfect 100mm spacing. However it doesn't center the dropouts over the axis of the steerer tube. You at least test that by riding no-hands. Off-center front-dropouts, even though they're space perfectly will cause your bike to lean to one side as you ride straight no-hands.

    I've got a couple of Shimano 7-speed freewheels I can give you for free, drop me an email and let me know what gear-ranges you want.

  16. #16
    crusty old wrench
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    BryE,

    your home brew drop out alignment method sounds pretty good.

    Remember this, though: it's more important that the drop outs remain parallel than whether or not they are the exactly the right width. Having the right width primarily affects how easily the wheel can be removed/installed, whereas the parallel-ness affects load on the axle, which affects durability. Since you're considering respacing the rear hub out to 126mm or 130mm to accomodate a 7 speed cluster, parallel drop outs are pretty important.

    While you're at the hardware store, think about this jig: 2 threaded rods; one for each drop out. 3 bolts per rod; two to locate the rod in the drop out (with big washers on either side of the drop out), one to have at the inside end of the rod, i.e inbetween the drop outs. Once both rods are firmly in the drop outs (in approximately the same spot along the slot), thread the 3rd bolt out to meet the other in the middle. If the drop outs are not close to parallel, the bolts will not come close to lining up with each other. Make sense? What this jig is trying to do is compare the drop out faces to each other within a millimeter or so, not eyeballing across the entire overlocknut dimension, i.e 126-130mm.

    This jig also approximates the purpose of a standard bike shop tool known as drop out alignment gauge. Every decent shop has one; you could even buy a set from Park, Stein, Var, et al. for less than $50 used if you don't want to fashion your own. The method is the same regardless.

    Good luck!
    1 speed's all you need.

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