T.R | Title | User | Personal Name | Date | Lines |
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1226.1 | Go Ahead and Spread | BOOKIE::CROCKER | | Tue Jun 27 1989 16:20 | 9 |
| Marty--
It's perfectly OK to spread a frame to accept 126mm axle spacing.
If the 7-speed appeals to you, you may as well go for it now, instead
of going halfway. Do recommend that you have the spreading done
by a reliable professional, since it's pretty easy to throw off
the balance of your frame when doing this.
Justin
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1226.2 | New chain | APOLLO::GOODWIN | in a spasm of lucidity... | Tue Jun 27 1989 16:27 | 8 |
| RE: .0
Don't forget to get a new chain as well. If you have a 5-speed the
chances are you have a thick chain on there and it won't work on all
cogs on the freewheel. Besides if you have more than 1500 miles on it
you should change it anyways.
Paul
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1226.3 | chain replacement frequency? | USCTR1::PJOHNSON | | Tue Jun 27 1989 16:51 | 7 |
| RE: .2
Is it really necessary to get a new chain every 1500 miles? I try
to keep mine clean and I replace it every year (approx. 4500mi last
yr), but every 1500 miles seems a little too frequent???
Phil
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1226.4 | | CSCOA3::HOOD_DO | | Tue Jun 27 1989 17:20 | 7 |
|
re: .1
How will they spread the frame? Do they heat the frame, or
will spreading the dropouts damage the paint?
Doug
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1226.5 | Void where prohibited, your mileage may vary | APOLLO::GOODWIN | in a spasm of lucidity... | Tue Jun 27 1989 17:29 | 15 |
| Chains stretch and when elongated do not seat themselves in the cogs
of the sprokets very well. In fact in extereme cases only the link at
the top of the sprocket is engaged. this causes excessive wear on the
teeth of the sprocket.
The rate at which the chain stretches depends a lot on the way you
ride. If you spin fast and never pull a lot of torque the chain will
last longer than if you are always trying to push big gears. Good
chains like the Sedissport and Dura-ace will be for a couple thousand
miles or more, Some of the cheaper chains less, bargain basement chains
last about 500. Your mileage may vary. If you are going to put on a new
freewheel you might as well spend the extra $10-$15 for a new chain and
not start wearing on the freewheel from day one.
Paul
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1226.6 | Still confused... | SHIGEO::SASAKI | Marty Sasaki LTN1-1/D07 226-6011 | Wed Jun 28 1989 00:28 | 11 |
| I'm still not sure what is involved with spreading the frame. Do
I need to take this to a bike shop and have them "spread" the frame.
Do I just push the dropouts apart when I put the hub in?
Thanks for the recommendations. I think I will go with the 7 speed
and change over to SIS. The bike is a really old Vita-Sprint (531
butted tubes, touring angles) and a new rear end will probably help
me put off buying a new bike until I can afford to get a really
nice one.
Marty Sasaki
|
1226.7 | Cold-set it. | BANZAI::FISHER | Rdb/VMS Dinosaur | Wed Jun 28 1989 08:22 | 9 |
| What shouldd happen is that the frame should be cold-set to the new
width. If this is done on a frame alignment table, they will clamp
down the frame and spread each of the dropouts 3 mm. Then they will
bend back the dropouts so that they are still parallel to each other.
Paul Randazzo in Tyngsboro can do that, I think Haggett's in Concord,
NH, can. Of course Peter Mooney at Belmont Wheelworks. All for a fee.
ed
|
1226.8 | You don't have to spend the money | AKOV11::FULLER | | Wed Jun 28 1989 09:24 | 6 |
| If you don't feel like spending money, you can put the wheel in
with some force. It is not necessary to go through the expense
of having it cold set. (I am not sure what the expense is, and
if I had it done, it would be done by an expert such as Peter Mooney)
steve
|
1226.9 | A real entertaining problem..... | SUSHI::KMACDONALD | Is there life after drywall? | Wed Jun 28 1989 11:26 | 9 |
| A problem I've seen once or twice with crunch-fitting a six-hub into a
five-hub space (or even just changing brands of freewheels...) is that
on some frames the clearance is so low that inserting a new freewheel
(that perhaps sits a mm farther out on the hub) can cause the chain to
jam between the smallest freewheel cog and the frame. If this happens
(it's fairly rare, but...) you may have to do some dinging around with
things like the hub axle spacers, etc. to be able to use the last cog.....
ken
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1226.10 | Paint Will Be OK | BOOKIE::CROCKER | | Wed Jun 28 1989 14:46 | 20 |
| Yes, you will have to increase the spacing on the freewheel side
if you're going to go 7-spd SIS. You also may need a longer axle.
These are fairly easy to find if you have a Campy Record hub--not
so easy with other brands.
While you can force a wider spaced rear hub between 120mm spaced
dropouts, remember that you have to force it whenever you are taking
the wheel out and reinserting it. I still think it's better to
get the frame spread, so wheel removal will be as simple as it
currently is. The spreading will not damage the paint.
As for chain replacement, with the Sedisport selling for between
$5 and $8, depending on where you get it, you'll find that regular
replacement (like every 1,500 miles) minimizes wear on freewheel,
chainrings, and derailleur pulleys. Chain replacement is kind of
like an oil change. If you don't do it, the machine still works,
but not as well.
Justin
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1226.11 | To set or not to set, ... | BANZAI::FISHER | Rdb/VMS Dinosaur | Thu Jun 29 1989 09:04 | 17 |
| There is a real difference in whether you cold-set the rear triangle.
If it is not set and you force it open to put in the rear wheel, the
stays will be in a constant state of stress as if a large weight of
arounf 50 lbs was continually bouncing on them. This should lead to
cracks.
If it is set, they will be forced to a new positiononce but they will
stay in that position.
I'm no expert but I think it makes sense.
Of course it also makes sense to just ride an old ten speed and be
happy with it but I suppose it's just not cool to only have a 5 speed
cluster. Think of all the weight you would save.
ed
|
1226.12 | But.. | ANT::CRITCHLOW | | Thu Jun 29 1989 09:25 | 8 |
| > Of course it also makes sense to just ride an old ten speed and be
> happy with it but I suppose it's just not cool to only have a 5 speed
> cluster. Think of all the weight you would save.
Do they make 5 speed indexed shifting systems?????
JC
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1226.13 | To modernize, you'll have to spread 'em. | BANZAI::FISHER | Rdb/VMS Dinosaur | Thu Jun 29 1989 10:49 | 5 |
| No, if yoiu want indexed shifting you gotta go 6 or 7 spd. Could
probably make 5 work but that would be like shutting off half the
valves on a ZR1.
ed
|
1226.14 | Five-speed indexing exists | JUMBLY::MACFADYEN | Hooker's Green Light | Tue Jul 04 1989 10:06 | 8 |
| Sorry to disagree with one as knowledgeable as Ed, but I have seen with
my own eyes this very week a 5-speed Shimano index system. I know it
was 5-speed because I too didn't expect to see it, so I counted the
cogs quite carefully. It was on child's bike, so I suppose it's low-end
stuff - I don't what you'd have to ask the shop for.
Rod
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1226.15 | in the UK? | NOVA::FISHER | Rdb/VMS Dinosaur | Wed Jul 05 1989 11:31 | 7 |
| re: .14: You saw it in the UK? I suspect that if it was on a child's
bike it's not something they push for after-market upgrades. I must
add that to my list of "available odds and ends, if you can find it."
Did you notice any other markings on the equipment?
ed
|
1226.16 | I thought Ed was a Guru ???? | GSFSWS::JSMITH | Jerry Smith - VAX SPM Product Mgmt. | Wed Jul 12 1989 12:34 | 17 |
| re:15
Ed,
Next time your in Sunshine Sports look at the Pugeot Ranger
with the 12 Inch frame. It has an indexed Shimano *5* speed
rear with no front shifting capability. Probably something
a lot of adults would also go for since the complexity of a
straight block 5 speed could even be handled by an old guy.
Seems that Bicycling or Cyclist recently did a Q and A on
this for someone wanting to convert their 10/12 speed to a
5 speed.
Gee, and I thought you knew *everything* about cycling :-)
Jerry
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1226.17 | go for it... | CSCOA5::HOOD_DO | | Fri Jul 21 1989 17:41 | 18 |
| re:basenote...
I put a 6speed wheel (specialized hub/rim that came on my Stumpjumper)
on a 5 speed Schwinn Sierra. When you realize that 5mm means
1/8 inch on each size, you really are not spreading the frame
very much. Structural integrity is NOT compromised. It is NOT a
hassle to spread the rear triangle (in fact, it spreads rather easily).
I don't think you would want to spread more that 1/8 on each side...
going from 5sp to 7sp would add 1/2 inch between dropouts.
When used with Shimano Deore shifters and derailler, you get TRUE
6 speed indexed shifting. Note that this was done on a mountain
bike, and road bikes may be more_fragile/more_precise.
In fact, when I think about it , I wonder if Shimano realizes
this? If so, it would explain why they add a gear to the freewheel
every couple of years...to get the previous million bikes at the
lesser speed to upgrade (MBA predicts Shimano will release 8sp
in 1990-1991).
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