v1nce
10-29-07, 01:01 PM
Sheeeez! It is nice to see Sheldon checking in! Cool! I hope you are well Sheldon.
As for not knowing who the man is, that had better be a joke!! :)
As for not knowing who the man is, that had better be a joke!! :)
Folding Bikes - I broke my Raleigh 20's SA 8sp hub gear
Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.stevegor
10-30-07, 05:57 AM
Sheeeez! It is nice to see Sheldon checking in! Cool! I hope you are well Sheldon.
As for not knowing who the man is, that had better be a joke!! :)
Yeah it was, but it seems like I ruffled some feathers, which was my naughty aim :D
As for not knowing who the man is, that had better be a joke!! :)
Yeah it was, but it seems like I ruffled some feathers, which was my naughty aim :D
jur
11-19-07, 05:19 PM
This weekend I finally reassembled my SA 8sp hub and put it back on the bike. I was waiting for quality bearings to arrive.
Number of items to report:
1. Take great care not to deform the bearing retainers. If you do, they will rub against the races and stuff up the friction. I spent a lot of time to try and fix them with zero success. :crash: Luckily due to the whole extra hub I had, I had spare retainers. Phew!
2. I drilled and tapped a 1/4" hole to accept an old SA oil port. I first thought it was 6mm because the thread matched a 6mm screw I tried, then on completing tapping I found it would not go in. No problem - re-tap with the tap held at sloppy angles. I installed the oil port on the angled part of the hub shell so drilling and tapping was easy due to the angle.
3. I oiled everything before putting it all back together and things are running a lot smoother than with the original gel lubricant.
4. The gear shift mech spring is somehow not nearly as stiff as before despite following the assembly procedure carefully. Or maybe due to following it. I have an idea on how to get the tension up which requires quite a bit of disassembly. Shifting the gears to work this morning was very light, IMHO too light to be ergonomically acceptable. I'll ride it like that for a while before making a decision on whether to up the spring tension.
5. Excess oil runs out immediately. As I suspected, the sealing is rudimentary at best, adequate for gel but pretty hopeless for thin oil. I stood the wheel at an angle overnight to encourage all excess to run out before final assembly on to the bike. For periodical lubrication, I will remove the wheel, lean it over optimally to the left side, saturate the hub with oil, backpedal to spead it all around, and lean it to the right again to let the excess run out again. This will also flush it. I envisage this procedure to be done once a year. Doing it this way also makes the oil port redundant as once the wheel is out, it is a piece of cake to take off some of the RH shifting parts to put oil in there.
6. Riding to work this morning: I was pretty unsure if it would work properly so I asked SWMBO to be on standby so I could call her in case of trouble to bail me out. But it all ran smoothly including shifting.
7. Efficiency: I imagine the efficiency to be quite a bit better. This is to be expected since the light oil necessarily runs with much less drag than the original gel. It really feels much easier to pedal. How much of this is due to placebo effect is hard to tell. One of the indicators is despite taking it easy to work this morning, the commuting time wasn't as long as I thought it might be. Another one is I am thinking all the time somehow the gearing became lower. Which is impossible of course, so I must be riding slightly faster with the same sort of effort.
Number of items to report:
1. Take great care not to deform the bearing retainers. If you do, they will rub against the races and stuff up the friction. I spent a lot of time to try and fix them with zero success. :crash: Luckily due to the whole extra hub I had, I had spare retainers. Phew!
2. I drilled and tapped a 1/4" hole to accept an old SA oil port. I first thought it was 6mm because the thread matched a 6mm screw I tried, then on completing tapping I found it would not go in. No problem - re-tap with the tap held at sloppy angles. I installed the oil port on the angled part of the hub shell so drilling and tapping was easy due to the angle.
3. I oiled everything before putting it all back together and things are running a lot smoother than with the original gel lubricant.
4. The gear shift mech spring is somehow not nearly as stiff as before despite following the assembly procedure carefully. Or maybe due to following it. I have an idea on how to get the tension up which requires quite a bit of disassembly. Shifting the gears to work this morning was very light, IMHO too light to be ergonomically acceptable. I'll ride it like that for a while before making a decision on whether to up the spring tension.
5. Excess oil runs out immediately. As I suspected, the sealing is rudimentary at best, adequate for gel but pretty hopeless for thin oil. I stood the wheel at an angle overnight to encourage all excess to run out before final assembly on to the bike. For periodical lubrication, I will remove the wheel, lean it over optimally to the left side, saturate the hub with oil, backpedal to spead it all around, and lean it to the right again to let the excess run out again. This will also flush it. I envisage this procedure to be done once a year. Doing it this way also makes the oil port redundant as once the wheel is out, it is a piece of cake to take off some of the RH shifting parts to put oil in there.
6. Riding to work this morning: I was pretty unsure if it would work properly so I asked SWMBO to be on standby so I could call her in case of trouble to bail me out. But it all ran smoothly including shifting.
7. Efficiency: I imagine the efficiency to be quite a bit better. This is to be expected since the light oil necessarily runs with much less drag than the original gel. It really feels much easier to pedal. How much of this is due to placebo effect is hard to tell. One of the indicators is despite taking it easy to work this morning, the commuting time wasn't as long as I thought it might be. Another one is I am thinking all the time somehow the gearing became lower. Which is impossible of course, so I must be riding slightly faster with the same sort of effort.
pm124
11-19-07, 05:39 PM
Hi Jur--Congrats on getting it all together. You are unquestionably a gifted mechanic. There aren't many folks that would have the courage to tackle that...certainly not me.
I just rebuilt my Chris King front hub. (Yes, I got it on sale a while back b/c it's pink.) They insist that one use their proprietary lube, but it seems to be about the same viscosity as Phil Wood, so I used that instead. Either way, it runs pretty stiff, so I'm tempted to go with oil rather than grease. Any thoughts on this? Would it be crazy to use Finish Line Wet or something similar in there?
My rear XTR hub spins much longer. Though I suspect this has much more to do with the nature of the seals than with the grease per se.
I just rebuilt my Chris King front hub. (Yes, I got it on sale a while back b/c it's pink.) They insist that one use their proprietary lube, but it seems to be about the same viscosity as Phil Wood, so I used that instead. Either way, it runs pretty stiff, so I'm tempted to go with oil rather than grease. Any thoughts on this? Would it be crazy to use Finish Line Wet or something similar in there?
My rear XTR hub spins much longer. Though I suspect this has much more to do with the nature of the seals than with the grease per se.
jur
11-19-07, 06:19 PM
Gifted - huh. Not half as gifted as I want to be, as I wouldn't have stuffed up the bearing retainers. :(
Regarding your hubs, I wouldn't regard myself as qualified to give advice, but one thing is that greased bearings have a run-in period, becoming smoother with time. And yes, seals can also stuff performance to some extent, so make sure the grooves in which the seals run are clean and oiled. Bearing pre-tension is even more important- make sure the bearings aren't so stiff that they are binding.
Regarding your hubs, I wouldn't regard myself as qualified to give advice, but one thing is that greased bearings have a run-in period, becoming smoother with time. And yes, seals can also stuff performance to some extent, so make sure the grooves in which the seals run are clean and oiled. Bearing pre-tension is even more important- make sure the bearings aren't so stiff that they are binding.
makeinu
11-19-07, 09:14 PM
Wow, jur. As always, I'm impressed.
EvilV
11-20-07, 03:26 AM
Glad it's all back together and seems to be working (except for the spring being too light). I suppose the light gear change thing couldn't be due to the lubricant change? Probably not as the spring would be the bigger factor in resisting the change.
I don't know how thin singer oil is, so I've no idea how long it will persist in the hub. I have been re lubing my simpler srf3 with a few drops of 10/30 engine oil every hundred miles. I extended that and looked inside after 150 recently and all was well wet, so I'm going to extend the oiling interval to 200 to see how it goes. Like you, I put in FAR too much at first and it made its way back out.
I thought the thing had got a lot more efficient too, so I don't think you are experiencing a placebo effect. It stands to reason that slippier lube will have an impact, particularly on yours which has cascaded planetary systems soaking up effort. One thing to watch might be that the oil port can allow the oil to move everywhere through the hub. I'm not sure what would happen if you were a bit on the mean side and some parts didn't get the oil. It might be worth overdoing it, spinning up the hub on the stand and then draining it back out of the open port into a receptacle. That way, you'd know that at that point in time, everything was oiled. My oil port is right over the gear ring, so I know that my drips are getting where they're needed. Personally, I'd rather overdo it a bit and have to wipe up after the first ride than under oil the thing. My regime shows tiny seepage at the bearings, so I'm happy nothing is dry.
I don't know how thin singer oil is, so I've no idea how long it will persist in the hub. I have been re lubing my simpler srf3 with a few drops of 10/30 engine oil every hundred miles. I extended that and looked inside after 150 recently and all was well wet, so I'm going to extend the oiling interval to 200 to see how it goes. Like you, I put in FAR too much at first and it made its way back out.
I thought the thing had got a lot more efficient too, so I don't think you are experiencing a placebo effect. It stands to reason that slippier lube will have an impact, particularly on yours which has cascaded planetary systems soaking up effort. One thing to watch might be that the oil port can allow the oil to move everywhere through the hub. I'm not sure what would happen if you were a bit on the mean side and some parts didn't get the oil. It might be worth overdoing it, spinning up the hub on the stand and then draining it back out of the open port into a receptacle. That way, you'd know that at that point in time, everything was oiled. My oil port is right over the gear ring, so I know that my drips are getting where they're needed. Personally, I'd rather overdo it a bit and have to wipe up after the first ride than under oil the thing. My regime shows tiny seepage at the bearings, so I'm happy nothing is dry.
jur
11-20-07, 05:47 AM
The problem with the 8sp gear mech is the little gears are all enclosed and the oil can't easily find its way inside to them all, which is why I'm thinking of drowning it once a year or whatever the distance interval. I put the oil port in a position where it can drip on the mech but time will tell how it will work. Unfortunately you can't see the innards without COMPLETE disassembly. So it's probably worth drowning, I just don't have a feel for how often. This is my workhorse commuter and I put on about 300km per week. I may take the wheel off and peek inside after a month to try and assess the need.
tgzzzz
11-20-07, 07:24 AM
Wow, jur. As always, I'm impressed.
Me too! This is what I'd hope to find on this forum rather than all that silly crap from yamcha.
Me too! This is what I'd hope to find on this forum rather than all that silly crap from yamcha.
BruceMetras
11-20-07, 09:20 AM
The problem with the 8sp gear mech is the little gears are all enclosed and the oil can't easily find its way inside to them all, which is why I'm thinking of drowning it once a year or whatever the distance interval. I put the oil port in a position where it can drip on the mech but time will tell how it will work. Unfortunately you can't see the innards without COMPLETE disassembly. So it's probably worth drowning, I just don't have a feel for how often. This is my workhorse commuter and I put on about 300km per week. I may take the wheel off and peek inside after a month to try and assess the need.
Congrats on the repair ... nice work!! Good that AE sent you a spare hub too, nice to have a few extra bits ... did you assemble it dry? no moly or the like, and then drown in oil once it was back together?
Also, I'm curious as to your commute times using your 20 with the 3spd and now the 8spd.. has there been a noticeable difference... what's the terrain like for you commute? I'm working up a sheet myself comparing speeds/times/heartrate for a couple of courses that I frequently ride using different folders/tires/gearing combos... lots of variables so it won't be scientific by any means, but a general pattern should emerge.. your runs are very informative ..
Congrats on the repair ... nice work!! Good that AE sent you a spare hub too, nice to have a few extra bits ... did you assemble it dry? no moly or the like, and then drown in oil once it was back together?
Also, I'm curious as to your commute times using your 20 with the 3spd and now the 8spd.. has there been a noticeable difference... what's the terrain like for you commute? I'm working up a sheet myself comparing speeds/times/heartrate for a couple of courses that I frequently ride using different folders/tires/gearing combos... lots of variables so it won't be scientific by any means, but a general pattern should emerge.. your runs are very informative ..
EvilV
11-20-07, 04:51 PM
The problem with the 8sp gear mech is the little gears are all enclosed and the oil can't easily find its way inside to them all, which is why I'm thinking of drowning it once a year or whatever the distance interval. I put the oil port in a position where it can drip on the mech but time will tell how it will work. Unfortunately you can't see the innards without COMPLETE disassembly. So it's probably worth drowning, I just don't have a feel for how often. This is my workhorse commuter and I put on about 300km per week. I may take the wheel off and peek inside after a month to try and assess the need.
Interesting.
Of course the beauty of the small gears running around the ring gear is that any oil on the ring gear is automatically redistributed around all the gears in that epicyclic set since they all mesh with the ring or with the planets in the case of the sun gear.
I think you'd be right to check it after a couple of months.
One thing I saw somewhere about the old three and four speed hubs that were oiled was that the writer asserted that you could tell if a hub was drying out because the sound of the pawls and dogs got louder and what he called 'bright'. You'd know then that there wasn't much oil on the moving parts and could put in some more.
To be honest, it would be no big deal to put in five cc and swirl the wheel up to speed for five minutes on the stand and then drain out the bulk of it by opening the port and turning the wheel down and collecting the surplus on a rag. I bet you could do that once or twice in a thousand miles if you put in three or four drops a week between times, just to let some spread through on the gears. A little goes a long way and since it is all cool running and pretty slow in terms of rubbing speed by comparison with a car engine, I think it will last well.
In the end - only empirical testing can say how it will work. The efficiency gains make it worthwhile, probably.
Interesting.
Of course the beauty of the small gears running around the ring gear is that any oil on the ring gear is automatically redistributed around all the gears in that epicyclic set since they all mesh with the ring or with the planets in the case of the sun gear.
I think you'd be right to check it after a couple of months.
One thing I saw somewhere about the old three and four speed hubs that were oiled was that the writer asserted that you could tell if a hub was drying out because the sound of the pawls and dogs got louder and what he called 'bright'. You'd know then that there wasn't much oil on the moving parts and could put in some more.
To be honest, it would be no big deal to put in five cc and swirl the wheel up to speed for five minutes on the stand and then drain out the bulk of it by opening the port and turning the wheel down and collecting the surplus on a rag. I bet you could do that once or twice in a thousand miles if you put in three or four drops a week between times, just to let some spread through on the gears. A little goes a long way and since it is all cool running and pretty slow in terms of rubbing speed by comparison with a car engine, I think it will last well.
In the end - only empirical testing can say how it will work. The efficiency gains make it worthwhile, probably.
jur
11-20-07, 07:59 PM
... did you assemble it dry? I oiled the planetary systems before assembling.
Also, I'm curious as to your commute times using your 20 with the 3spd and now the 8spd.. has there been a noticeable difference... what's the terrain like for you commute? I'm working up a sheet myself comparing speeds/times/heartrate for a couple of courses that I frequently ride using different folders/tires/gearing combos... lots of variables so it won't be scientific by any means, but a general pattern should emerge.. your runs are very informative ..Unfortunately I'm not meticulous at all so I can only give vague subjective indications... my impression is that the 3sp and 8sp were about the same as I was able to achieve a sub-60m commute on both hubs. Perhaps the 3sp was more efficient since with it I was obviously unable to always select the optimum gear, but still achieved sub 60m. Riding the 3sp made me wonder if I should put the 8sp back on since I "didn't need 8 speeds, 3 are just fine." The 3sp was ridden with light oil.
My commute starts and ends with hills with flattish terrain in between. Here (http://www.bikely.com/maps/bike-path/MELB-Mt-Evelyn-to-Blackburn-North-28km-daily-commute) it is - click on Show > Elevation profile to see.
Also, I'm curious as to your commute times using your 20 with the 3spd and now the 8spd.. has there been a noticeable difference... what's the terrain like for you commute? I'm working up a sheet myself comparing speeds/times/heartrate for a couple of courses that I frequently ride using different folders/tires/gearing combos... lots of variables so it won't be scientific by any means, but a general pattern should emerge.. your runs are very informative ..Unfortunately I'm not meticulous at all so I can only give vague subjective indications... my impression is that the 3sp and 8sp were about the same as I was able to achieve a sub-60m commute on both hubs. Perhaps the 3sp was more efficient since with it I was obviously unable to always select the optimum gear, but still achieved sub 60m. Riding the 3sp made me wonder if I should put the 8sp back on since I "didn't need 8 speeds, 3 are just fine." The 3sp was ridden with light oil.
My commute starts and ends with hills with flattish terrain in between. Here (http://www.bikely.com/maps/bike-path/MELB-Mt-Evelyn-to-Blackburn-North-28km-daily-commute) it is - click on Show > Elevation profile to see.
BruceMetras
11-20-07, 09:03 PM
My commute starts and ends with hills with flattish terrain in between. Here (http://www.bikely.com/maps/bike-path/MELB-Mt-Evelyn-to-Blackburn-North-28km-daily-commute) it is - click on Show > Elevation profile to see.
Thanks! nice to have all the comments .. you really must be bookin' to average better than 17mph along that run... I was in satellite view to see what the surface was for the paths, couldn't really tell for sure ... are they paved or grass or ?? What's your commute time after work?.... thanks again for the linky..
Bruce
Thanks! nice to have all the comments .. you really must be bookin' to average better than 17mph along that run... I was in satellite view to see what the surface was for the paths, couldn't really tell for sure ... are they paved or grass or ?? What's your commute time after work?.... thanks again for the linky..
Bruce
jur
11-20-07, 09:53 PM
All the paths are paved. The only off-road section is near home where there's a km of dirt. On the R20 I have to open all taps wide open to make the 27.4km in an hour. On the first steep downhill I routinely go 75km/h, even on the Mini. On the long very slight downhill run next to the creek I have to average well above 32km/h to make up for slower sections. The homeward run is about 10min longer, and I don't want to go fast then - not after a day's work. :)
On my Swift I can average 30.1km/h to work - it is much faster.
On my Swift I can average 30.1km/h to work - it is much faster.
stevegor
11-21-07, 05:21 AM
Jur,
For someone who has never raced (??), or has expressed a desire of not wanting too (??), you certainly have a respectable weekly km tally and times....and on a R20 :eek:
Are you sure you never raced, even in the Veteran class?
We could have used you off the A grade and scratch marks in some big open road races I used to ride in.
For someone who has never raced (??), or has expressed a desire of not wanting too (??), you certainly have a respectable weekly km tally and times....and on a R20 :eek:
Are you sure you never raced, even in the Veteran class?
We could have used you off the A grade and scratch marks in some big open road races I used to ride in.
jur
11-21-07, 05:41 AM
Nah, just dreaming of a long-gone mis-spent childhood... :D
Rode the R20 in BIG wet today. I think at one stage the hub may have gotten close to being submerged. NOT GOOD. Water got in and I had to take the blooming thing apart again. :mad: The "seal" around the driver is not really a seal, it only pretends to be one.
*sigh* Back to the drawing board. I have to improve that so-called seal. Maybe pack it with grease. I'm fresh out of ideas...
Rode the R20 in BIG wet today. I think at one stage the hub may have gotten close to being submerged. NOT GOOD. Water got in and I had to take the blooming thing apart again. :mad: The "seal" around the driver is not really a seal, it only pretends to be one.
*sigh* Back to the drawing board. I have to improve that so-called seal. Maybe pack it with grease. I'm fresh out of ideas...
EvilV
11-21-07, 07:28 AM
I thought Australia had a drought! That was some shower to put your hub into ten inches of water. Maybe you need some kind of submarine prop shaft seal for that driver. If it went into the drink, any bike hub seal would leak. If it didn't, it would be so tight that it would soak up power. How tight is the oil cap seal?
:)
:)
LWaB
11-21-07, 02:00 PM
I thought Australia had a drought!
Australia is a big place...
Australia is a big place...
EvilV
11-21-07, 02:20 PM
Yes of course. I thought Victoria had a drought though. Anyway - it was a joke, sort of.
stevegor
11-21-07, 03:05 PM
We are in a nationwide drought, apprently the worst in more than a hunderd years....so when rain does come it's very welcome, some of our local water storeages have been lower than 5% capacity!!!
I bought my SA 8 spd hub because of the supposed reputation internal gear hubs have of being all weather units, you know......low maintenance, easy to clean, good in the wet etc, but it seems that even if I get mine slighty moist, the next day it starts making those weird sounds, like the bearings have a little coating of rust on them. It feels like it catches somewhere when you lift the wheel and spin it, then it goes away after a day or so......hope I'm not hurting it. Maybe I won't ride it in the rain??
I could give the seal a good coat of marine grease every time it rains.
I bought my SA 8 spd hub because of the supposed reputation internal gear hubs have of being all weather units, you know......low maintenance, easy to clean, good in the wet etc, but it seems that even if I get mine slighty moist, the next day it starts making those weird sounds, like the bearings have a little coating of rust on them. It feels like it catches somewhere when you lift the wheel and spin it, then it goes away after a day or so......hope I'm not hurting it. Maybe I won't ride it in the rain??
I could give the seal a good coat of marine grease every time it rains.
jur
11-21-07, 04:25 PM
I read up some stuff by Jobst Brandt last night on seals; labyrinth seals are apparently pretty good as long as you don't submerge them, so that's 2 out of 3 that's good. The driver seal I will have to think about, maybe use a grease that won't form an emulsion with water, like silicone grease (?).
Anyway, the one underwater place I unwisely rode through was probably the culprit, I wouldn't do this again. (We have a severe drought, this rain is the first good one since July.)
Anyway, the one underwater place I unwisely rode through was probably the culprit, I wouldn't do this again. (We have a severe drought, this rain is the first good one since July.)
jur
11-25-07, 06:04 AM
I put it back together again, and the bearings had rusted from one measly ride in a bit of rain. I should never have done the under-water riding trick... :mad: replaced the balls with fresh ones (luckily I bought loads of spare ones :D ).
The bearings and seals I did with silicone grease. More drag but I think it will withstand a big wet better. I'd rather have a bit of drag as stripping it after every rainstorm is a bit of a drag (how's that for the week's worst pun?).
I also repositioned the shifting tension spring and it's back to normal now.
The bearings and seals I did with silicone grease. More drag but I think it will withstand a big wet better. I'd rather have a bit of drag as stripping it after every rainstorm is a bit of a drag (how's that for the week's worst pun?).
I also repositioned the shifting tension spring and it's back to normal now.
stevegor
11-25-07, 07:16 PM
Jur,
Seeing now that you're a seasoned SA 8 spd pull-aparterer and an A grade fixerator....maybe I could send you my 2 hubs for servicing and mods when they need them ;)
Seeing now that you're a seasoned SA 8 spd pull-aparterer and an A grade fixerator....maybe I could send you my 2 hubs for servicing and mods when they need them ;)
jur
11-25-07, 07:22 PM
heh, don't you dare... let's ride together instead. You doing the Alpine Classic? I'm entered for the 200km at 6:20am. Not on the R20 though - strictly Swift.
stevegor
11-26-07, 06:18 AM
heh, don't you dare... let's ride together instead. You doing the Alpine Classic? I'm entered for the 200km at 6:20am. Not on the R20 though - strictly Swift.
Unfortunately no.....
But I'm preparing a steel (Italian??) roadie frame with Ultegra 52/42/30 triple cranks to do rides like that in the future.....nice and light.....I'll send you some pics when it's done, it's black like the Wasp but the hi- lights are red, ie: saddle, bar tape and bidons and I've painted the heart shape cut outs in the front lugs bright red. Wheels are Velocity deep V shod with Vittoria rubino reds.
It's currently running a 52/39 set up....lovely to ride...even though it hasn't got small wheels ;)
Unfortunately no.....
But I'm preparing a steel (Italian??) roadie frame with Ultegra 52/42/30 triple cranks to do rides like that in the future.....nice and light.....I'll send you some pics when it's done, it's black like the Wasp but the hi- lights are red, ie: saddle, bar tape and bidons and I've painted the heart shape cut outs in the front lugs bright red. Wheels are Velocity deep V shod with Vittoria rubino reds.
It's currently running a 52/39 set up....lovely to ride...even though it hasn't got small wheels ;)
tgzzzz
11-26-07, 06:52 AM
On my Swift I can average 30.1km/h to work - it is much faster.
Is the big difference in ET mostly due to the weight differential, Swift to modded-but-still-heavy R20, or would you credit the efficiency of the Swift, i.e. the upgraded wheels & hubs/narrow tires, less drag of the derailler compared to the SA8 hub, maybe more aero positioning, ...?
On the hub immersion deal, I'm dissapointed to read of rust after one incident when we know your "new" hub was full of oil. The old 3 speeds were indestructable in comparison.
When I had the LBS install my sealed BB, she made a big point (too big I thought at the time) about NOT washing the bike. I thought she meant because of the BB, but what's the big deal if it's sealed? Now I wonder if she was warning me about the poor sealing of the SA8 hub. I live at the beach. Rinsing things is a way of life. I don't ride my new DT on the beach, however. It's too cool. And I have my passed-over hybrid for that.
Is the big difference in ET mostly due to the weight differential, Swift to modded-but-still-heavy R20, or would you credit the efficiency of the Swift, i.e. the upgraded wheels & hubs/narrow tires, less drag of the derailler compared to the SA8 hub, maybe more aero positioning, ...?
On the hub immersion deal, I'm dissapointed to read of rust after one incident when we know your "new" hub was full of oil. The old 3 speeds were indestructable in comparison.
When I had the LBS install my sealed BB, she made a big point (too big I thought at the time) about NOT washing the bike. I thought she meant because of the BB, but what's the big deal if it's sealed? Now I wonder if she was warning me about the poor sealing of the SA8 hub. I live at the beach. Rinsing things is a way of life. I don't ride my new DT on the beach, however. It's too cool. And I have my passed-over hybrid for that.
jur
11-26-07, 05:39 PM
Is the big difference in ET mostly due to the weight differential, Swift to modded-but-still-heavy R20, or would you credit the efficiency of the Swift, i.e. the upgraded wheels & hubs/narrow tires, less drag of the derailler compared to the SA8 hub, maybe more aero positioning, ...?I don't think there is one single thing that makes all the difference. The much lighter weight would be a big thing, accelerating all that extra mass on the R20 tends to tire me and I have therefore less energy left over. But the other items, ie no suspension soaking up some energy, thinner tyres so more aero (this is true of the whole frame, really, especially the forks), and drivetrain efficiency all play their part. Another item where derailers shine is in being able to shift under load - you can just keep pedalling with just a small momentary easing off, whereas with the SA hub you need to stop pedalling for a moment.
On the hub immersion deal, I'm dissapointed to read of rust after one incident when we know your "new" hub was full of oil. The old 3 speeds were indestructable in comparison.Well perhaps it is not reasonable to expect labyrinth seals to keep water out under those severe conditions. I was disappointed too. Hopefully the silicone grease will tend to mix less with water and not form an emulsion which will cause rust.
When I had the LBS install my sealed BB, she made a big point (too big I thought at the time) about NOT washing the bike. I thought she meant because of the BB, but what's the big deal if it's sealed? Now I wonder if she was warning me about the poor sealing of the SA8 hub. I live at the beach. Rinsing things is a way of life. I don't ride my new DT on the beach, however. It's too cool. And I have my passed-over hybrid for that.I wash my bikes but take care not to direct a hard water spray near the bearings area. In fact I usually use a bucket with sudsy water and a paint brush, and use a compressor to blow it dry, again not directing an air jet at the bearing seals.
On the hub immersion deal, I'm dissapointed to read of rust after one incident when we know your "new" hub was full of oil. The old 3 speeds were indestructable in comparison.Well perhaps it is not reasonable to expect labyrinth seals to keep water out under those severe conditions. I was disappointed too. Hopefully the silicone grease will tend to mix less with water and not form an emulsion which will cause rust.
When I had the LBS install my sealed BB, she made a big point (too big I thought at the time) about NOT washing the bike. I thought she meant because of the BB, but what's the big deal if it's sealed? Now I wonder if she was warning me about the poor sealing of the SA8 hub. I live at the beach. Rinsing things is a way of life. I don't ride my new DT on the beach, however. It's too cool. And I have my passed-over hybrid for that.I wash my bikes but take care not to direct a hard water spray near the bearings area. In fact I usually use a bucket with sudsy water and a paint brush, and use a compressor to blow it dry, again not directing an air jet at the bearing seals.
tgzzzz
11-27-07, 08:04 AM
Well perhaps it is not reasonable to expect labyrinth seals to keep water out under those severe conditions.
I hadn't heard of this kind of seal but a quick turn to Wikipedia fixed that. Interesting indeed. And to build a hub with a water/oil tight seal adds a lot of friction apparently. I suppose that's why it was filled with the higher viscosity gel-type lube initially. Most of us would never notice the higher friction. Look for my hub in your mailbox along with Stevegor's at maintenance time.
I hadn't heard of this kind of seal but a quick turn to Wikipedia fixed that. Interesting indeed. And to build a hub with a water/oil tight seal adds a lot of friction apparently. I suppose that's why it was filled with the higher viscosity gel-type lube initially. Most of us would never notice the higher friction. Look for my hub in your mailbox along with Stevegor's at maintenance time.
Sheldon Brown
11-28-07, 09:46 PM
Someone wrote:
"...it was filled with the higher viscosity gel-type lube initially."
The "gel-type lube" is more commonly called "grease." ;-)
Sheldon "Cyclexicographer" Brown
"...it was filled with the higher viscosity gel-type lube initially."
The "gel-type lube" is more commonly called "grease." ;-)
Sheldon "Cyclexicographer" Brown
jur
11-28-07, 09:57 PM
Someone wrote:
"...it was filled with the higher viscosity gel-type lube initially."
The "gel-type lube" is more commonly called "grease." ;-)
Sheldon "Cyclexicographer" BrownAh, but you haven't seen this stuff. It doesn't draw threads or peaks like common grease. It feels very 'thin' like oil yet doesn't run like oil.
"...it was filled with the higher viscosity gel-type lube initially."
The "gel-type lube" is more commonly called "grease." ;-)
Sheldon "Cyclexicographer" BrownAh, but you haven't seen this stuff. It doesn't draw threads or peaks like common grease. It feels very 'thin' like oil yet doesn't run like oil.
jur
04-28-08, 11:44 PM
My R20's SA8sp hub is proving very problematic. The bearings are all rusted up again. I fixed this a previous time after freshly rebuilding the hub. This morning I thought I might take the R20 for commuting seeing that the weather was wet, so I tested the hub action and it sounds like it's grinding rocks so bad it is. I haven't ridden it for a while now since I was using the Swift for commuting in preparation for the Fleche-Opperman 24h trial.
Looks like the 3sp wheel is going back on. I am a bit dis-hearted by my lack of progress on this hub. Not sure what I'm doing wrong, because the Mini's hub is just fine (but that one hasn't ridden in the wet to the same degree). I feel like ditching the hub. Nothing is worth that much maintenance.
Looks like the 3sp wheel is going back on. I am a bit dis-hearted by my lack of progress on this hub. Not sure what I'm doing wrong, because the Mini's hub is just fine (but that one hasn't ridden in the wet to the same degree). I feel like ditching the hub. Nothing is worth that much maintenance.
DVC45
04-29-08, 01:25 AM
I wish I read this post long ago. I took my Downtube VIIIH onto the beach two weeks ago, since then, it started to have some grinding sound, though, its quite and not exactly noisy, its making me paranoid.
I called one of my LBS to have it serviced, but I was told they don't do Internal gear hubs. I'm afraid the other LBS would say the same.
It still shift and works fine, it just have the anoying sound. I hope this is not the beginning of its end yet, as I really like this bike.
I called one of my LBS to have it serviced, but I was told they don't do Internal gear hubs. I'm afraid the other LBS would say the same.
It still shift and works fine, it just have the anoying sound. I hope this is not the beginning of its end yet, as I really like this bike.
mulleady
04-29-08, 03:00 AM
Sad reading this when Sheldon passed away recently. I'm relaively knew to the cycling forum but soon learnt who this wonderful character was. 63 was quite young really, very sad.
When I spoke to Steve Parry the other week in the UK he advised against modifying a Brompton with an 8 speed SA hub and that they are prone to breaking within 6 months in some cases. I guess it isn't just the early models and the quality isn't as good as the older SA hubs since they transferred production to the Far East.
When I spoke to Steve Parry the other week in the UK he advised against modifying a Brompton with an 8 speed SA hub and that they are prone to breaking within 6 months in some cases. I guess it isn't just the early models and the quality isn't as good as the older SA hubs since they transferred production to the Far East.
K6-III
04-29-08, 12:37 PM
From the failures posted so far, the failures seem to be attributable to poor metallurgy for the planet gears and planet cage. The suns/planets need to be made of good hardened steel, with very careful machining to avoid stress concentrations. The planet cage looks like it could use a redesign, perhaps with carbon fiber reinforcement, to make it stronger with minimal weight penalty.
We'll have to see how the updated "wide range" Sturmey 8 plays out.
We'll have to see how the updated "wide range" Sturmey 8 plays out.
jur
04-29-08, 07:38 PM
The wide(r) range hub is evidently a slightly modded version of the current one; the step-up ratios are slightly larger but the mech is identical with 3 cascaded planetary systems. The hub appears a little bigger so is likely to be a bit heavier too. The shift adjustment sensitivity has also been addressed.
jur
05-04-08, 06:52 PM
I stripped the hub again this weekend, completely washed out all previous lube. The bearings weren't rusted as I thought. I am not sure at all why it was 'crushing rocks'. Perhaps the graphite powder I mixed in with the oil was to blame.
I put in a new product I got last weekend, Rocol cable grease with moly. It goes on very thin, frothing, then thickens up a bit as solvent evaporates, won't run out and the moly eases friction. It feels great now, better than when new I imagine. Used it to commute this morning, all is fine again.
This time for sure?
I put in a new product I got last weekend, Rocol cable grease with moly. It goes on very thin, frothing, then thickens up a bit as solvent evaporates, won't run out and the moly eases friction. It feels great now, better than when new I imagine. Used it to commute this morning, all is fine again.
This time for sure?
stevegor
05-04-08, 10:36 PM
Jur,
I had that sound as well, and also as hub felt like it was dragging on something, but when it was dismantled there were no obvious causes, so the bearings were washed and re-greased, the hub put back together and it still made that sound. On closer examination, the plastic disc, (can't remember the proper name for it), that the gear cable hooks into had a tiny groove wore into it from who knows what, maybe a bit of grit, but after another clean, it's all clear..so far as well.
I had that sound as well, and also as hub felt like it was dragging on something, but when it was dismantled there were no obvious causes, so the bearings were washed and re-greased, the hub put back together and it still made that sound. On closer examination, the plastic disc, (can't remember the proper name for it), that the gear cable hooks into had a tiny groove wore into it from who knows what, maybe a bit of grit, but after another clean, it's all clear..so far as well.
jur
05-05-08, 08:32 AM
Well tonight after 1 day of commuting, I imagine it is already not as smooth as before. :mad: I am such a bloomin perfectionist. I probably need to back off the left cone a tad.