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byrd48 08-17-12 02:09 PM

Upgrading to an 8 speed
 
I have an old Hardrock and want to upgrade it to an 8 speed and therefore looking at a new rear wheel. The current wheel measures at 28mm outer width. When I look at Amazon, I see several 25mm (1 inch) and quite a few more 1.5 inch wheels, but no 28mm. Any recommendations on going with the 1 inch vs 1.5 inch with the new wheel? I have plenty of clearance on the caliper brakes to accommodate a wider wheel. I am running 26 x 1.95 tires, I assume they will fit either. Any difference in the ride characteristics?
Thanks in advance.
Jon

jimc101 08-17-12 02:35 PM

Upgrade from what, 5/6/7 speed?

The measurement you are giving have nothing to do with any speed upgrade, what your interested in is the OLD of the hub, if it's freewheel or freehub, how many speed your rear dérailleur is, how many speed your chain, cassette, right hand shifter are.

If you have a caliper brake on an MTB, this would indicate that its either from from the 1980's, which will give lots of issue with nothing matching current standards, it's a 1990's ultra low end BSO, which has been re-badged as a Hardrock, or they are not calipers, and you need to ID what type of brake you actually have.

For the rim, you won't notice the difference in 25mm-28mm other than the 28mm will probably weigh more.

bobotech 08-17-12 02:53 PM

Yeah, upgrading from what speed? if you are upgrading to 8 speed from 7, you won't get much of an upgrade for the time and money involved. Just not worth it unless your current parts are in poor shape.

When you upgrade to a new speed, you will need a new wheel with a modern 8-9-10 speed freehub, a new 8 speed cassette, new shifters (8 speed), and at that point, might as well buy a new chain.

If your current rear speed is a 7 speed, the most likely your current rear derailleur should work fine. If that one doesn't work, you will then have to buy a new rear derailleur as well but that usually isn't a requirement. However if the rear derailleur is a cheap claw style SIS derailleur, then that is another flag that your bike isn't a hardrock. I think that most Harrdrocks came with frame mounted rear derailleur hangers and would not use a cheap claw style derailleur.

byrd48 08-17-12 05:28 PM

HI,
Sorry for not enough info, it's a 93 model with a six speed cogset. It has 135mm OLD. The original rear shifter is an Altus c-20 and the housing is broken where the cable comes in. It still works, but doesn't shift smoothly and is just waiting to break altogether. So there aren't very many good 6 speed shifters out there and I would like a few more gears. The current chainring is 28-38-48, and the rear cogset is 14-28, which is fairly high gearing for a mountain bike. I'm using it as a commuter and would like to get a 12-32 8 speed on the rear to give a little more low range and more gears to work with in between. I'm also looking at a Deore m591 rear derailleur. I picked the bike up for $75 and was hoping to stay under $200 for the upgrades. I was contemplating whether I should go ahead to 9 or 10 speed, but it seems to get more expensive when you go above 8 and I've heard the chains don't last as long.
Thanks again for the input.
Jon

byrd48 08-17-12 05:37 PM

I apologize, they are not calipers, they are cantilevers

Bill Kapaun 08-17-12 08:11 PM

IF you feel 8 speed is wonderful, think how much more wonderful 9 speed would.

You have to change shifters- Shop around a bit online and you'll find 9 speed aren't that much more than 8.
Cassette is about $3 more than 8 speed.
Chain varies, but call it $10 more.

9 Speed comes in a lot more different cog combinations than 8.

bobotech 08-17-12 08:16 PM


Originally Posted by byrd48 (Post 14619956)
HI,
Sorry for not enough info, it's a 93 model with a six speed cogset. It has 135mm OLD. The original rear shifter is an Altus c-20 and the housing is broken where the cable comes in. It still works, but doesn't shift smoothly and is just waiting to break altogether. So there aren't very many good 6 speed shifters out there and I would like a few more gears. The current chainring is 28-38-48, and the rear cogset is 14-28, which is fairly high gearing for a mountain bike. I'm using it as a commuter and would like to get a 12-32 8 speed on the rear to give a little more low range and more gears to work with in between. I'm also looking at a Deore m591 rear derailleur. I picked the bike up for $75 and was hoping to stay under $200 for the upgrades. I was contemplating whether I should go ahead to 9 or 10 speed, but it seems to get more expensive when you go above 8 and I've heard the chains don't last as long.
Thanks again for the input.
Jon

Better info. Good thing about the canti brakes, if you had cheap calipers, I would have suggested to dump it and get something else. Now you need to see if you have a freewheel or a freehub. If you have a freehub rear wheel, then you have a couple more options. If you have a freewheel rear hub, I would dump the whole rear wheel and look at your local bike coop for a replacement wheel that has an 8 speed freehub and an 8 speed cassette.

If your rear wheel is currently a freehub, then you could remove the existing freehub and replace it with the longer 8-9-10 speed freehub that hopefully yoour bike coop will have in stock. Then you might have to redish the wheel but that isn't too hard and the coop should be able to help you with that.

Once you get the rear wheel situated, then buy yourself an 8 speed cassette of your choice. I just use whatever is laying around at my bike coop.

Then buy a set of 8 speed shifters and a new chain (under 10 dollars at walmart or around 12-15 new at your LBS). Do NOT get integrated shifters and brake levers. If you buy a modern combo brake/shifter setup, they will be for V-brakes and not suitable for your canti brakes. You really should get a set of dedicated 8 speed shifter pods and keep using your current brake levers for best results.

Buy a new set of brake pads, they are probably old and dried out.

Don't bother with 10 speed, too expensive. If you have the extra cash, 9 speed would be an nice upgrade but will be a little more money.

The Deore rear derailluer is a good choice. I have a bunch of bikes using Deore parts and they are all good solid reliable parts.

Are you sure your bike isn't a 7 speed? I really think that even the 93 hardrock had a 7 speed rear cassette and freehub.

Buy all new shifter cables and housings and replace them. You can get a cheap brake and shifter cable set at walmart for under 9 dollars but I strongly suggest you get true dedicated bundled wire shifter housing at your LBS for the shift cables. The walmart kit only has brake housing and while it will work, it compresses which isn't that good for index shifting.

LarDasse74 08-17-12 08:34 PM

The hardrock was an entry level bike and almost definitely came with a freewheel.

If the rear derailleur is still functioning, there is no need to replace. A derailleur designed for 6 speed should work perfectly with an 8 speed shifter and cassette.

bobotech 08-17-12 08:46 PM


Originally Posted by LarDasse74 (Post 14620623)
The hardrock was an entry level bike and almost definitely came with a freewheel.

If the rear derailleur is still functioning, there is no need to replace. A derailleur designed for 6 speed should work perfectly with an 8 speed shifter and cassette.

Every Hardrock that has come through my bike coop has had a freehub. I know for a fact that several of the older Hardrocks with the steel frames from the '90s had freehubs because I checked. I even almost bought one from 97 that had a freehub. I know that my personal 2002 Hardrock came with the freehub.

I'm not saying that all of them had freehubs, but for the most part, LBS only entry level mountain bikes seem to have freehubs. I know that most of the Giants, Treks, Diamondback, and even Schwinn LBS mountain bikes from the '90s seem to have 7 speed freehubs.

byrd48 08-17-12 08:51 PM

Yes, I'm not set on replacing the rear derailleur necessarily. I spoke with several LBS (and the coop) about redishing the current wheel, but none recommended it. I don't know if it's just a skill set they don't have or if it would not be cheaper for me to just buy a new wheel with hub already in place. Rear wheels seem to start at $40 and go up, with the 8/9 speed hub and skewers.

In addition to the shifters being broken, the chain skips about an eighth of a turn of the crankset sometimes going from 2nd to 3rd, and not when under pressure. This could be due to that shifter cable not being seated correctly due to the broken shifter housing.

I definitely know it's a 6 speed, but whether it's cassette or freewheel, I don't know. One tech at an LBS said that with some of the 6 speed freehubs, the smallest cog screwed on and held it together, and if that was the case, it might be just as difficult to remove as a freewheel. At any rate, it's a non-issue, I'm pretty set on upgrading to get more gears.

So the choice at this point is 8 or 9 speed.

But back to the original question, If I buy a new rear wheel, should I stick with the 1 inch or go with 1.5 inches or does it make any difference (other than the 1.5 being fatter than the front wheel if I don't replace both)?

Bill Kapaun 08-17-12 10:14 PM


Originally Posted by byrd48 (Post 14620677)
...........But back to the original question, If I buy a new rear wheel, should I stick with the 1 inch or go with 1.5 inches or does it make any difference (other than the 1.5 being fatter than the front wheel if I don't replace both)?

What size tires do you intend to use?
IF skinny street slicks, a narrow rim would save a bit of weight and be a better match.
IF fat knobby tires, the wider rim would make sense.

BTW, your LBS probably isn't interested in trying to dish an old wheel-
Old, corroded nipples can be a can of worms. Labor charge vs a new inexpensive wheel would probably leave a bad taste in your mouth.

IF it's a 6 speed, it's likely a free wheel. Uniglide hubs went out in the late 80's to early 90?'s

There's different levels of Hard Rocks.
See if you can better identify the year & model on bikepedia.com

byrd48 08-17-12 10:49 PM

I already have Continental Town and Country 26 x 1.90 tires on it now, just bought them a few weeks back. It's definitely a 93 Hardrock, the bikepedia specs are: http://www.bikepedia.com/QuickBike/B...e#.UC8a8d1lSOs

I saved the old knobby tires that came on it, but I'm using it for urban commuting and there are lots of potholes, broken pavement, storm drains and various other obstacles. Would the wider rims be less susceptible to warping, etc?

jimc101 08-17-12 11:48 PM


Originally Posted by byrd48 (Post 14620936)
I saved the old knobby tires that came on it, but I'm using it for urban commuting and there are lots of potholes, broken pavement, storm drains and various other obstacles. Would the wider rims be less susceptible to warping, etc?

It's all down the be build quality of the wheels, well built and they will be fine, poorly built, and they won't hold up. Wider rims won't help if they have been badly built to begin with.

Bill Kapaun 08-18-12 12:14 AM


Originally Posted by byrd48 (Post 14620936)
I already have Continental Town and Country 26 x 1.90 tires on it now, just bought them a few weeks back. It's definitely a 93 Hardrock, the bikepedia specs are: http://www.bikepedia.com/QuickBike/B...e#.UC8a8d1lSOs

I saved the old knobby tires that came on it, but I'm using it for urban commuting and there are lots of potholes, broken pavement, storm drains and various other obstacles. Would the wider rims be less susceptible to warping, etc?

According to the bikepedia link, your bike should be a 7 speed.
Did you count the cog the chain is on?
Possibly the rear wheel was swapped out? Does the rim match the front?

byrd48 08-22-12 07:44 PM

The rims match and there are 6 cogs on the back. The shifter is a 6 speed as well, so it's possible they were both changed, although Bikepedia does list the Altus c20 shifters as stock.
The wheels I'm considering are these:
http://www.amazon.com/Avenir-Weinman...I1J2EI09YMHQCX

http://www.amazon.com/Sta-Tru-Silver...eed+rear+wheel

fietsbob 08-22-12 09:23 PM

Why , what gear ratio are you lacking? 12 instead of 13 for the high gear?

know speeds are just a cog count number , ratios [(A:B) a&b tooth counts]
are what matters, really..

Bill Kapaun 08-22-12 10:53 PM


Originally Posted by byrd48 (Post 14640704)
The rims match and there are 6 cogs on the back. The shifter is a 6 speed as well, so it's possible they were both changed, although Bikepedia does list the Altus c20 shifters as stock.
The wheels I'm considering are these:
http://www.amazon.com/Avenir-Weinman...I1J2EI09YMHQCX



http://www.amazon.com/Sta-Tru-Silver...eed+rear+wheel


I'd probably go with the Weinman since it's a name we've heard of. The other????

Both are inexpensive wheels, but should be suitable if you aren't one that runs into curbs etc.

A few months back I bought a similar set for back up wheels.
There were obviously "reject" wheels with multiple "flat spots" that had been actually marked with a paint stick.
2-3 hours with the truing stand and tension meter and I was actually able to get them in pretty decent shape.
Now when I say "flat spots", they weren't severe, but they were noticeable. For a $40 wheel, I wouldn't really expect much better.

dabac 08-23-12 02:38 AM


Originally Posted by byrd48 (Post 14619956)
....the current chainring is 28-38-48, and the rear cogset is 14-28, which is fairly high gearing for a mountain bike.

Well, yeah, 28-28 is fairly high for a MTB.

But consider your own words:

Originally Posted by byrd48 (Post 14619956)
...... I'm using it as a commuter...

On paved roads and light loads, a 1:1 ratio should get you up plenty of hills.


Originally Posted by byrd48 (Post 14619956)
....would like to get a 12-32 8 speed on the rear to give a little more low range

Do you really need that? Honestly, how often do you use the 28:28 combo?


Originally Posted by byrd48 (Post 14619956)
..would like to get a 12-32 8 speed on the rear to give....more gears to work with in between.

Have you done the math on that?

Why not pay a visit to http://www.sheldonbrown.com/gears/, punch the numbers and see what they say.
Unless you really need the lower offered by the 32, seems like there's a possibility that you'll end up with bigger steps between the gears with that setup.
You've got a 6 tooth overall range increase, and two more gears to spread it over. Might not do that much.

Asi 08-23-12 03:06 AM


Originally Posted by Bill Kapaun (Post 14641406)
I'd probably go with the Weinman since it's a name we've heard of. The other????

Both are inexpensive wheels, but should be suitable if you aren't one that runs into curbs etc.

A few months back I bought a similar set for back up wheels.
There were obviously "reject" wheels with multiple "flat spots" that had been actually marked with a paint stick.
2-3 hours with the truing stand and tension meter and I was actually able to get them in pretty decent shape.
Now when I say "flat spots", they weren't severe, but they were noticeable. For a $40 wheel, I wouldn't really expect much better.

That weinman is known for older large reach and clearance brake calipers not for rims/wheels. And those wheels have joytec hubs (that are on the junky side of the line. It's 3$ a joytec front hub and 5-6$ for a rear hub.. I'd avoid that, I've tossed a joytec front hub in less than 3000km - cracked raceway on the hub part)

For that between those two i'd definitely go with the other one. that have a shimano rear hub. and it has alex rims (that is ok, and known manufacturer of budget rims that work well, yet singlewall is not the most desirable rim), also dt spokes are good. It's a better option all the way.

byrd48 08-23-12 07:48 PM

Thanks,
I looked at REI and found these two. The lower end model has Shimano Altus hub and 36 spokes with the more expensive one having Deore with 32 spokes. It seems like the higher the price, the fewer spokes they offer.

http://www.rei.com/product/770553/al...101-rear-wheel

http://www.rei.com/product/770551/de...eed-rear-wheel

byrd48 08-23-12 07:52 PM

I almost never use the front chainring during commuting, however there are times when I do hit a long uphill stretch at a point when my legs are gassed and end up dropping all the way down. I did save my knobby tires to use as a mountain bike on occasion, so while the low range may not see much use in commuting, it would be useful to have. It is a good point about the steps between gears, I do need to give that some more thought. Thanks


Originally Posted by dabac (Post 14641636)
Well, yeah, 28-28 is fairly high for a MTB.

But consider your own words:


On paved roads and light loads, a 1:1 ratio should get you up plenty of hills.



Do you really need that? Honestly, how often do you use the 28:28 combo?



Have you done the math on that?

Why not pay a visit to http://www.sheldonbrown.com/gears/, punch the numbers and see what they say.
Unless you really need the lower offered by the 32, seems like there's a possibility that you'll end up with bigger steps between the gears with that setup.
You've got a 6 tooth overall range increase, and two more gears to spread it over. Might not do that much.



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