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Post your Centurion Ironman.. For the love of 80s paint jobs!

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Post your Centurion Ironman.. For the love of 80s paint jobs!

Old 12-22-18, 08:58 AM
  #5801  
seypat
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Originally Posted by TXsailor View Post
She would like a triple. Its not really needed most places around Bowie but we ride some other hilly areas. We rode up Mt. Scott in the Wichita Mountains a while back. I had a triple and she has a compact. She said she wished she had brought my Giant Escape hybrid. That was the first bike she rode much. Send me a pm and we will work out something.
PM sent.
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Old 12-22-18, 09:06 AM
  #5802  
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Originally Posted by TXsailor View Post



Mount Scott Lawton Oklahoma
This is my granddaughter. I am so wrapped around her little finger that its sort of pathetic.
Beautiful granddaughter with a huge smile on her face! Which means Grandpa is as happy as can be.
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Old 12-22-18, 09:25 AM
  #5803  
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So, I am going to send TXsailor that crank. But I/we need the wisdom of the IM thread. I think the crank will be set up as a triple. I have 50-52 big rings, 40-42 middle, and 28-30 grannies. Someone help us out with the range the GPX RD will run successfully. TXsailor, what size cassette are you going to run?
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Old 12-22-18, 10:15 AM
  #5804  
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Originally Posted by seypat View Post
So, I am going to send TXsailor that crank. But I/we need the wisdom of the IM thread. I think the crank will be set up as a triple. I have 50-52 big rings, 40-42 middle, and 28-30 grannies. Someone help us out with the range the GPX RD will run successfully. TXsailor, what size cassette are you going to run?
We haven't got that far yet but if we switch to 10 speed I will probably use 11-28 if it stays 7 speed I will switch the freewheel to something around 13-28. The Mavic 40 wheels are a little out of true and I don't know if the spoke nipples are going to budge. I am going to put some PB blaster on them and let them sit before I even try to true them. They look a little crusty. I took some fine rubbing compound to a really ugly spot on the frame and it shined up pretty easily. I think it will look pretty good when I get it apart and buff the whole frame. The compound turned black very quickly so I wonder if the clear coat is baked off in the California sun.
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Old 12-22-18, 10:53 AM
  #5805  
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Let it stew through the holidays. With all of the knowledge on this thread, we can come up with something special.
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Old 12-22-18, 04:12 PM
  #5806  
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That triple crank/BB will be fine from 7-10 speeds, but she would need to change out the RD and the FD to handle it. The GPX that came on there will not.

If she stays 7sp, then 3x7, the GPX shifters will work. So will the brake levers, and calipers, and wheels. What's nice is that with a triple, she really doesn't have to go 13-28.

If she elects to go 8/9/10, she'll need another rear wheel, then shifters, FD, RD.

My take is to build her the nicest 3x7 you can, conserve the money spent, make sure it fits, and let her ride it until she grows out of it or can outride it. She will always like having the coolest bike around, and likely hang onto it. Good grandpa.

I know steelbikeguy and I saw several young ladies on steel at the Hilly Hundred; Fujis, Miyatas, and a nice Bianchi. They were all triples, and we made sure to tell each one how great their bike was.
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Old 12-22-18, 09:06 PM
  #5807  
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Originally Posted by RobbieTunes View Post
That triple crank/BB will be fine from 7-10 speeds, but she would need to change out the RD and the FD to handle it. The GPX that came on there will not.

If she stays 7sp, then 3x7, the GPX shifters will work. So will the brake levers, and calipers, and wheels. What's nice is that with a triple, she really doesn't have to go 13-28.

If she elects to go 8/9/10, she'll need another rear wheel, then shifters, FD, RD.

My take is to build her the nicest 3x7 you can, conserve the money spent, make sure it fits, and let her ride it until she grows out of it or can outride it. She will always like having the coolest bike around, and likely hang onto it. Good grandpa.

I know steelbikeguy and I saw several young ladies on steel at the Hilly Hundred; Fujis, Miyatas, and a nice Bianchi. They were all triples, and we made sure to tell each one how great their bike was.
We talked it over today and she sat on the bike with it on the trainer. It looks like it will work for her but we might need to switch to a seat post with no offset. We decided to tear it down clean it up service everything and do exactly what you said. Make it 3X7 with the crank set from seypat and let her ride it and see how she likes it. I have a Exage triple derailleur set I can put on it or maybe I can find another that looks better with the GPX. The wheels (Mavic M40) are probably usable as is but are a little out. The nipples have some corrosion on them so truing them might not be easy. I put some PB Blaster on them and will see what happens. If she really wants to we might make it 3x10 sometime in the future. This won't be her only bike she has a nice Fuji Roubaix that she bought new 5 years ago with the money from her first job. She isn't a typical young lady she loves old things. Old country music and classic cars and she thinks she will really like this old bike.
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Old 12-22-18, 10:59 PM
  #5808  
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Need to send her some Patsy Cline.
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Old 12-23-18, 12:56 AM
  #5809  
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This is how it was when I unboxed it. Since the rear skewer was backwards I put the front the same way.
Originally Posted by RobbieTunes View Post
Need to send her some Patsy Cline.
She loves Patsy Cline but she told me if she could only listen to one artist the rest of her life it would be Merle.
To change the subject I am having trouble believing no one commented on the skewer in this picture. That's the way it was when it came in. I spotted it in the add and figured the seller knew nothing about bikes. I am not sure if that's good or bad.
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Old 12-23-18, 03:04 AM
  #5810  
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+1 on Merle. Possibly the best voice in country music. Gun to my head favorite song of his would have to be The way i am.
My freaking tablet is out (some kinda update needs to happen) and of course i dont know anything about it and my wife has put it on the back burner til after the jolidays. Meanwhile im forced to use my phone which is just about done and i cant see pics clearly.
Anyways next week ill be making some changes to one of my Ironman. It depends on the number of speeds the gripshift i bought is. Ive ssid it before, but eventually id like my '87 to 7 speed , my '88 to be 8 speed and my '89 to be 9 speed. And also eventually all of them Dura Ace. So we shall see.
Meanwhile im hoping santa brings me a new phone.
Later Irongents.
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Old 12-23-18, 05:04 AM
  #5811  
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@TXsailor: That GPX rear derailleur will handle a 14-28 freewheel like the SunRace I'm using. But it's very picky about clearance. The 14 cog and chain just barely clear the dropout. I may try a 13-28 next, although technically that exceeds what Suntour said the GPX can handle.

Frankly I'd choose the desired gearing first based on rider preferences and not worry about trying to make the GPX group fit. Personally I'm annoyed by the GPX group more than satisfied. The rear derailleur on mine drags the entire drivetrain in the big chainring. I'd suggest swapping out the rear derailleur for a suitable long cage RD and toss the GPX into the parts bin.

It's difficult to describe but easy to demonstrate. On a functioning bike with GPX rear derailleur, put the bike on a trainer or sturdy workstand. With the chain in the small chainring spin up the rear wheel fast, then turn the crank by hand just enough to not engage the drivetrain -- you just want to feel the relative effort needed to turn the cranks without moving the wheel. It should be relatively easy.

Repeat this with the chain in the big ring. If it's like mine it will suddenly feel like the brakes are dragging or someone is putting friction on the chain. The angle and tension of the GPX rear derailleur create some unusual resistance to free spinning. Relieving tension on the p-knuckle pivot spring helps. This doesn't happen with other derailleurs I've tried, including an older Shimano 600. The GPX RD creates enough resistance to rob at least 5 watts and probably more. It's just a chore to ride the bike in the original condition in the big ring.

I've tried a few tricks to fix the problem but it's just a bad design.

Adding one or two extra links to create a little chain sag helps a bit. But it's not the ideal solution.

I'm modifying the RD to use lower tension in the p-knuckle spring (drilling an extra hole with a moto tool). Most rear derailleurs I've disassembled have two spring retention holes to set tension. The GPX had a pilot hole for the second hole but it looked like the factory didn't finish the job.

I'm also betting a smaller big chainring will help. I've ordered a 50T Vuelta chainring which should arrive next week. I ordered one last week but the vendor delivered a mislabeled 56T chainring, which I can't use, although a local friend can.

And I might shave a bit of material off the cage edges where it rubs the 28 cog no matter how I adjust the B-screw.

And if none of this helps I'll ditch the entire GPX group. The Accushift mechanism is extremely finicky anyway. Without the right freewheel, chain, etc., it won't index shift reliably. And the friction mode is mediocre. If adjusted for good shifting feel it'll creep and ghost shift. If I crank down the tension screw until it doesn't creep or ghost shift, the friction shifting loses any tactile feel.

After a year of messing with it I'm fed up. If modifying the p-knuckle spring tension and shaving a bit of material off the cage doesn't help I'm gonna dump the entire GPX group in a bin and start over with something else. I may switch to bar end shifters for my Ironman and put the older Shimano 600 group back on.

So I'd suggest doing that right from the beginning with your bike. Ditch the GPX derailleurs and Accushift downtube shifter. Find the gears your granddaughter wants and get the derailleurs and shifter to suit that.

Our turf around Fort Worth is pretty similar to yours, and I'm familiar with Bowie which is a bit hillier. My Univega Via Carisma has perfect gearing for this terrain: a 30/40/50 triple, a 7-speed 13-28 cassette (which I recently upgraded to 8-speed 12-32, even better). A Shimano Exage 500CX group and long cage rear derailleur. No drivetrain drag. It worked fine in indexed mode with the original thumb shifters but those wore out -- the holes that supported the mounting pivot pins eventually wore enough that the pins popped out. Rather than fix 'em I switched to Shimano bar end shifters which work great in friction mode (the index mode didn't quite match the MicroShift brand 8-speed cassette).

My Univega weighs right at 30 lbs as I ride it. We have a few short steep hills of 8%-11%, and occasionally I'll dip into the 30T chainring and 32 cog for minimal effort while climbing and it works great. Usually I'm in the middle 40T chainring and use the entire cassette -- doesn't appear to be any crosschaining problems. I seldom go fast enough to need the 50T big ring and 12 cog, although occasionally I do on some downhills.

Unless she really needs or wants a triple on the Ironman, I'd bet a 50/38 double chainring combo and 13-28 freewheel would do fine. I'm not a strong climber and the 39T Vuelta small chainring and 28T cog have been enough for the climbs I encounter locally, because the Ironman is lighter than my Univega. Otherwise consider a wheelset or hub for a cassette and try the MicroShift brand 8-speed 12-32, which is a good value at well under $20.
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Old 12-23-18, 09:25 AM
  #5812  
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I have this off my Purple Haze that we may start with. Its triple stuff and seemed to work well. I only rode it a little before I tore it apart and put the 10 speed drive train on it. She thinks she would really like a triple since she lives near a area called Silver Lakes. It has some MONSTER hills. One is called the Silver Lakes Wall and only a few people have actually made it up it. I finally did on my 6th try. The first two were on my hybrid and I couldn't keep the front wheel down, The next 4 were on my Origin8 which has a low gear of 30/28. She also wants to do Mt. Scott again and she really struggled on her Fuji when we did it. She was a little disappointed that her old grandpa made it to the top non stop and she had to stop a couple of times.

Exage group
If we go this route the only thing we would need to get would be a chain and the crank from seypat. I'm not sure what we would do on the brake levers. Hers have no boots on them at all and the GPX boots seem to be impossible to find. Maybe a new set or the 105 levers I got from a BF member that I have been saving for my blue & white bike.
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Old 12-23-18, 09:37 AM
  #5813  
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You'll be fine with that Exage/Light Action stuff, just fine, and it will match the GPX brake calipers, so with @seypat's crankset, could be a good one.

As far as the brake hoods for Suntour GPX, well, not much in the market. I'd forsake those, and if you need some 105 levers with hoods, I can hook you up via @seypat, and if you want (non-sprung) 600's with white hoods, I can hook you up from here.

As far as wheels, @seypat has a set from an Ironman, Wolber Super Alpine with 105 hubs that will take a 7-sp freewheel, Araya CTL-370 rims. You are welcome to them, and you'd have @seedsbelize to thank. Between us, we can put her on a nice 3x7 setup that will work just fine. Get her riding, climbing, and "Ironing."

The only problem she'll then have is suitors. Who wouldn't want to chat up the lady on the Ironman? You may have to play watchdog grandpa.
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Old 12-23-18, 09:39 AM
  #5814  
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Originally Posted by canklecat View Post
@TXsailor: That GPX rear derailleur will handle a 14-28 freewheel like the SunRace I'm using. But it's very picky about clearance. The 14 cog and chain just barely clear the dropout. I may try a 13-28 next, although technically that exceeds what Suntour said the GPX can handle.

Frankly I'd choose the desired gearing first based on rider preferences and not worry about trying to make the GPX group fit. Personally I'm annoyed by the GPX group more than satisfied. The rear derailleur on mine drags the entire drivetrain in the big chainring. I'd suggest swapping out the rear derailleur for a suitable long cage RD and toss the GPX into the parts bin.

It's difficult to describe but easy to demonstrate. On a functioning bike with GPX rear derailleur, put the bike on a trainer or sturdy workstand. With the chain in the small chainring spin up the rear wheel fast, then turn the crank by hand just enough to not engage the drivetrain -- you just want to feel the relative effort needed to turn the cranks without moving the wheel. It should be relatively easy.

Repeat this with the chain in the big ring. If it's like mine it will suddenly feel like the brakes are dragging or someone is putting friction on the chain. The angle and tension of the GPX rear derailleur create some unusual resistance to free spinning. Relieving tension on the p-knuckle pivot spring helps. This doesn't happen with other derailleurs I've tried, including an older Shimano 600. The GPX RD creates enough resistance to rob at least 5 watts and probably more. It's just a chore to ride the bike in the original condition in the big ring.

I've tried a few tricks to fix the problem but it's just a bad design.

Adding one or two extra links to create a little chain sag helps a bit. But it's not the ideal solution.

I'm modifying the RD to use lower tension in the p-knuckle spring (drilling an extra hole with a moto tool). Most rear derailleurs I've disassembled have two spring retention holes to set tension. The GPX had a pilot hole for the second hole but it looked like the factory didn't finish the job.

I'm also betting a smaller big chainring will help. I've ordered a 50T Vuelta chainring which should arrive next week. I ordered one last week but the vendor delivered a mislabeled 56T chainring, which I can't use, although a local friend can.

And I might shave a bit of material off the cage edges where it rubs the 28 cog no matter how I adjust the B-screw.

And if none of this helps I'll ditch the entire GPX group. The Accushift mechanism is extremely finicky anyway. Without the right freewheel, chain, etc., it won't index shift reliably. And the friction mode is mediocre. If adjusted for good shifting feel it'll creep and ghost shift. If I crank down the tension screw until it doesn't creep or ghost shift, the friction shifting loses any tactile feel.

After a year of messing with it I'm fed up. If modifying the p-knuckle spring tension and shaving a bit of material off the cage doesn't help I'm gonna dump the entire GPX group in a bin and start over with something else. I may switch to bar end shifters for my Ironman and put the older Shimano 600 group back on.

So I'd suggest doing that right from the beginning with your bike. Ditch the GPX derailleurs and Accushift downtube shifter. Find the gears your granddaughter wants and get the derailleurs and shifter to suit that.

Our turf around Fort Worth is pretty similar to yours, and I'm familiar with Bowie which is a bit hillier. My Univega Via Carisma has perfect gearing for this terrain: a 30/40/50 triple, a 7-speed 13-28 cassette (which I recently upgraded to 8-speed 12-32, even better). A Shimano Exage 500CX group and long cage rear derailleur. No drivetrain drag. It worked fine in indexed mode with the original thumb shifters but those wore out -- the holes that supported the mounting pivot pins eventually wore enough that the pins popped out. Rather than fix 'em I switched to Shimano bar end shifters which work great in friction mode (the index mode didn't quite match the MicroShift brand 8-speed cassette).

My Univega weighs right at 30 lbs as I ride it. We have a few short steep hills of 8%-11%, and occasionally I'll dip into the 30T chainring and 32 cog for minimal effort while climbing and it works great. Usually I'm in the middle 40T chainring and use the entire cassette -- doesn't appear to be any crosschaining problems. I seldom go fast enough to need the 50T big ring and 12 cog, although occasionally I do on some downhills.

Unless she really needs or wants a triple on the Ironman, I'd bet a 50/38 double chainring combo and 13-28 freewheel would do fine. I'm not a strong climber and the 39T Vuelta small chainring and 28T cog have been enough for the climbs I encounter locally, because the Ironman is lighter than my Univega. Otherwise consider a wheelset or hub for a cassette and try the MicroShift brand 8-speed 12-32, which is a good value at well under $20.
Never had a problem with GPX, and I'm about to build one with it. What kind of condition are your brake levers/hoods?
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Old 12-23-18, 11:03 AM
  #5815  
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The IM with the parts that can be harvested is pictured in post 5728, page 230. I will wait and see what needs to be shipped. Still need to know what size rings to put on the crank.
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Old 12-23-18, 12:19 PM
  #5816  
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Originally Posted by seypat View Post
The IM with the parts that can be harvested is pictured in post 5728, page 230. I will wait and see what needs to be shipped. Still need to know what size rings to put on the crank.
I think something around 52 38 30 or maybe 28 if the exage derailleurs will handle that much range. Her wheels are pretty sad looking and the spoke nipples are corroded some so decent wheels would be nice. I think she would prefer black brake hoods with the black bike. If you will send me a request on paypal I will get you the funds. I'll pm you with the paypal info.

You guys are amazing. This is going to be so much fun . I'll order her cables & a new chain probably a Sram PC 850 unless someone knows one that works better. That's what I put on my blue & white expert with the stock GPX stuff and it seems to work pretty good. I used a Sunrace 13-28 freewheel on it. It does seem to have more drag with the GPX derailleur as @canklecat mentioned but I haven't rode it much lately since I have the purple one going.
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Old 12-23-18, 12:49 PM
  #5817  
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Originally Posted by RobbieTunes View Post
Never had a problem with GPX, and I'm about to build one with it. What kind of condition are your brake levers/hoods?
The entire group is in pretty good shape, just scuffs here and there. Hoods are still pliable, not gummy or cracked. There's just something about that GPX rear derailleur that isn't right and I'm tired of messing with it. Life is too short for that kind of aggravation. I just wasted a weekend trying to get the spring tension where I want it. The convenience of the Accushift index mode isn't worth the aggravation.

If the springs were compatible I'd swap between the GPX and Shimano 600 rear derailleurs, but there's no point messing up a derailleur that already works. I just need some shifters that work in friction mode -- another aggravation about the GPX system. The friction mode is a half-hearted afterthought that barely works compared with well designed friction shifters. And there's no practical way to disassemble and reassemble the module to try to tweak the friction mode.

I'll admit I may be picky about some drivetrain drag that amounts to maybe 5-10 watts, but it's annoying and I've never seen this on any other bike from that era. Every time I see a comparable road bike I check the drivetrain to see if it's a common problem. It ain't. Mine has distinctly more drag in the big chainring. It's like pedaling while the brakes are dragging. I've gotten to the point where I avoid the big ring until it's absolutely necessary, even if it means cross-chaining in the little ring.
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Old 12-23-18, 07:14 PM
  #5818  
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Okay, I think I got the problem with the GPX rear derailleur sorted out Sunday. I took a 23 mile ride on a familiar route I've ridden hundreds of times and know every inch and how I usually perform. I set some of my fastest times of the year despite my legs feeling tight and sluggish. That's how much difference the drag and lack of drag makes in the drivetrain. Just a few more watts that goes into forward motion rather than fighting the bike.

I adjusted the spring tension after getting a tip from this video by RJ the Bike Guy. He twists the post that supports the lower knuckle spring and locks the cage to the derailleur body. Didn't occur to me that post could be twisted to be sure the cage locks up properly after resetting the spring tension. Problem solved.


Then I put the original Suntour 13-24 freewheel back on. I preferred the 14-28 SunRace -- much easier on my knees while climbing -- but it had a couple of problems. The 14 tooth smallest cog forced the chain much too close to the chainstay/dropouts -- it actually scraped the paint in some positions, limiting the use of the long horizontal adjustable dropouts. And the freewheel had developed a rattle -- I'm hoping it's just a loose lockring. Anyway, the 13-24 Suntour works better overall, although it doesn't shift as smoothly as the SunRace freewheels, which are better ramped.

And I left the chain a couple of links longer than technically recommended. This relieved some of the tension and odd angle of the rear derailleur that was creating some drag. There's still enough tension in the RD's cage pivot range to take up the slack, so the chain doesn't sag.

No more excessive tension or drag when the chain is in the big ring.

I'd still prefer a 13-28 freewheel, but I might be able to accomplish the same thing by switching to a 50T big chainring and 38T small ring. Amazon is re-sending the chainring after getting my order wrong last week.
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Old 12-23-18, 10:08 PM
  #5819  
TXsailor
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@canklecat I put a Sunrace13-28 on my '89 with the GPX drive train and it works pretty good. I run my chains as long as possible (55 links) I don't worry about a few grams and don't like the derailleur being tight if I accidentally get in big ring big cog. I usually have to run the b-screw pretty far in. My bike has 52/42 chain rings. Jenson has the 13-28 for $9.99 but to get free shipping you have to spend $50. I'll probably order one for the granddaughter's bike as soon as I need enough other stuff to get free shipping.
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Old 12-24-18, 11:25 AM
  #5820  
seypat
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Update on the wheel set I have being talked about. Hubs are 105 1050. Rear hub is a FH-1050, which takes a Uniglide cassette. Good news as people know, because you can switch the freehub body for about $20 and run modern Hyperglide cassettes. I don't know if you can put an 8-10 speed body on, but rrcardr and Robbie do. Let them chime in so we can move the project along. It is coming together!
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Old 12-24-18, 11:51 AM
  #5821  
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Originally Posted by seypat View Post
Update on the wheel set I have being talked about. Hubs are 105 1050. Rear hub is a FH-1050, which takes a Uniglide cassette. Good news as people know, because you can switch the freehub body for about $20 and run modern Hyperglide cassettes. I don't know if you can put an 8-10 speed body on, but rrcardr and Robbie do. Let them chime in so we can move the project along. It is coming together!
Uniglide is something I haven't messed with yet but it looks like I am about to.

We tore the bike down yesterday and I started buffing the faded paint. It is going to shine up pretty good. I was worried since it was nearly white in places where it must have sat in the sun for years. I also took the calipers apart as they were gummed up. I figured out how to get them back together and made a little tutorial, I put it on the main C&V page since I figured Centurion wasn't the only bike with GPX brakes.

Last edited by TXsailor; 12-24-18 at 12:09 PM.
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Old 12-24-18, 12:23 PM
  #5822  
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Yes, swapping out the freehub is quick and easy. Just buy one with a 'female' base and you should be good to go, will accept HG cassettes of 7-8-9-10 speeds (7 requires a 4.5mm spacer behind the cassette). Remove a four mm spacer from the left side of the axle when you do this and you can even use the old axle. Wheel should be redished.
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Old 12-24-18, 01:47 PM
  #5823  
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Pricey, but seldom-sighted, 1985 Centurion Prestige on fleaBay.

https://www.ebay.com/itm/Awesome-Vin...H-e9:rk:2:pf:0

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Old 12-24-18, 03:44 PM
  #5824  
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I like it , I could buy it , put $300. in it and have a $ 900. bike worth $ 300 . But It's not about the worth of the bike it's all about the bike .
Please read rule # 4 Velominati ? The Rules Isn't that right tex ?
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Old 12-24-18, 03:51 PM
  #5825  
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Originally Posted by rccardr View Post
Yes, swapping out the freehub is quick and easy. Just buy one with a 'female' base and you should be good to go, will accept HG cassettes of 7-8-9-10 speeds (7 requires a 4.5mm spacer behind the cassette). Remove a four mm spacer from the left side of the axle when you do this and you can even use the old axle. Wheel should be redished.
Like this?
https://www.jensonusa.com/Shimano-M5...sugg_q=freehub
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