Cassette customizing....sort of....
 

Hi all,

Could use some knowledgeable feedback and insight on this....

I have about a decade-old+ Specialized Hardrock MTB (got ~17K miles on it and it's still in great shape!!). Did some serious maintenance work over the past ~ 5 years which included replacing the cassette and chain. Replaced the original Sun Race 7-sp w/a Shimano HG-50 7-sp, 11-28 and have been running well since then. Unfortunately, I did not pay attention to the chain wear and I now have to again replace the chain and cassette.

I'd like to stay with the 11-28 (I like the top end...I will eventually convert to an 8-sp, just not right now), but I've discovered an HG-50 in a 7-sp, 11-28 version is somewhat rare (aren't many of those around from any mfg).

One of my thoughts is to take an 8-sp, 11-32 cassette, strip off the 32T cog to leave an 11-28, 7-sp cassette. I know there's a difference in both cog and spacer thickness (.2 mm total). I was thinking that if I could take the spacers from my current cassette and use those on the new cassette, I could bring the cog-to-cog spacing very close to the 5 mm spec of the old cassette.

Any experience on this from anyone? Also, I have seen Shimano HG-41, HG-31, and HG-51 cassettes being offered (tho, can't seem to find anything about them on the Shimano site). Any thoughts on these?

Thanks in advance for any help....

Cheers....Steph

Did you completely burn that new HG cassette or just the two highest gears? If you only have to change those last two smallest cogs and use the 7speed spacers you should be OK. Seven speeds didn't need the precision of the 'new and improved' 9&10 speeds.

If you can compromise on a 12x28, Loose Screws is running a special on Shimano HG50 7-speed cassettes in 12x28 at $26 right now. http://loosescrews.com/?d=single&item_id=LS-5948WF

Thanks, folks, for the info. I appreciate it.

As for wear...most of the wear is in the top gear (11T). Less in the 6th and 5th. I typically start in 3rd (mostly flat riding) so the 1st 2 gears have seen no wear and the 3rd and 4th a bit more. I was thinking I might have to use the old spacers for the new cassette. It sounds like there is enough slop in the design that the .2mm difference (5 mm vs 4.8 mm) center-to-center isn't enough of a concern. I might try it both ways just to see for sure.

Re: the HG-30 link on Amazon....any idea if that is better, equal or worse in quality/capability than the HG-50? Is it a replacement?

Re: 12-28. Thanks but I've really enjoyed having the 11T as my top gear.

Thanks again....Cheers...Steph

You can buy 11T (cassette) cogs separately, too.

Just discovered this on Sheldon's site-
The CS-HG30-I is an Interactive Glide cassette with wider sprockets and narrower spacers, and must be used with Interactive Glide chain."

HG-50 is lower end (Altus)

Wow, good catch Bill. I had no idea Shimano was still making IG cassettes. Not to worry, Sheldon says you can use regular SRAM chains with them.

Once again, thanks for the input.

I've seen the Sheldon Brown (RIP) postings and they have been very helpful for me.

As for getting just an 11T cog, I prob'ly need 6th gear (13T), as well (Chain needs replacing, too). And from the little I looked (or rather, found), 2 cogs will prob'ly cost me as much as a whole new cassette. Which leads me to.....

I was doing some more research and discovered an HG-30 7 sp, 11-28T cassette with the same steps as my current cassette (No muss, no fuss). And the price was almost 1/2 that of going thru Performance Bike for the same cassette, so I'm ordering up 2!!! Funny part? It's at Walmart (and no shipping if I pick it up at the store :) Here's the link (if anyone else is interested....they also have an HG-50 8 sp for the same price): http://www.walmart.com/ip/Shimano-Ca...-30-7/13012504

Looks like I've saved myself from having to adapt (to) an 8-sp cassette, for now (I expect the time is coming :(

Again, I appreciate the feedback.

Cheers...Steph

when you eventually upgrade to 8 speed, don't.
Just go to 9.
You need new shifters for both, or stay with friction if that's what you have.
Cost of the cassette isn't much different.
9 has way more combinations to choose from.
You need a 9 speed chain, but you'll probably be getting a new chain anyway, so that'll be just a few bucks more than an 8 speed.

I still don't see a lot of need for a 9 sped and the more expensive chain when 8 speed parts and chain are abundant and less expensive and still run a lot of 6-7 speed drives with cassettes and freewheels.

Have a little edge in that I have everything I need to rebuild older cassettes and freewheels and a good stock of Uniglide parts.

11-28 7-speed for $19 shipped: http://www.ebay.com/itm/SHIMANO-7-SP...item43ad582b29

As to why you're killing the smallest cogs, are you using them frequently with the two smaller chainrings? Or have you just put a ton of miles on and forgot to check on the chain?

Cassette customizing....sort of....
 

I think I saw that on ebay at some point in my search (Went back and saw that the same seller has the CS-HG30 for the same price). Thanks for the reminder. Still don't know for sure what the difference is between cassette models (i.e. HG30, HG-31, HG-40, HG-41, HG-50, in particular). My assumption is the higher the number, the better the quality/material?? If I believe the ebay seller's pix are accurate (close up says they are), then the HG-30 and HG-41 appear to be made of the same, or similar, material. Any difference is just not clear to me.

Your 2nd assumption is more accurate (I think I mentioned my lack of attentitive maintenance early on). I spend most of my time in 7th gear. I mostly do paved roads/trails with some off-road paths. I do oil (dry lightening) the chain fairly often. And, as I also mentioned above, I have ~5K miles (give or take) on the current chain/cassette set. If I had monitored the chain better, I might be replacing only it.

Steph

However you go, if indeed 7 or 8 speed, throw on a 9spd (4400) tiagra long cage derailluer. They're low bucks and the chain will shift quick and smooth. I did a bit of 7-speed non-related cassette cog swapping a while back that ended as thus:

a fresh 13-23 w/HG chain and had a 9-speed 14 cog and an 8-speed 18 cog and it all worked in an adequate fashion (filing to get the ramps close). After a while I decided to try the Tiagra I had laying about and the fool thing improved a good deal.

I've since returned to 9-speed but I rode that frankenstein smallblock for alotta miles.

Harris Cyclery and Universal Cycles still carry them.
Sence your bike is probably 135mm spaced you have the advantage of running a 8 or 9 spd setup without much issue. (You'd probably need a new rear derailleur/chain for the 9spd but 9cogs offer you the ability to have your LBS build you a nice close even spaced setup )

Nothing magical about a Tiagra derailer. Any Shimano derailer above the bottom barrel junk will shift just fine. Also Tiagra is a road derailer and the OP has a MTB, so that would limit the max cog to ~28T or so.

Didn't imply magic. Just relating my experience.

'sall good.

Rich,

Tried to respond to your private message, but apparently I don't have enough posts to qualify :(

Anyway, thanks for the input. I had wanted to ask you a question, but it turns out you've answered it for me below. The only thing I don't know is if my current freehub could handle an 8-sp cassette (certainly not a 9-spd). I suspect by the time I figure out all the mods I need to make, and given the age of the bike, it may turn out to be more cost-effective to buy a new bike. However, with the new cassette and a backup for later, I've got a bit of time to think about that.

Again, appreciate your (and everyone else's) input on this.

Cheers...and safe riding....Steph

If you have a 7-speed cassette on there with no extra spacers behind it, you have a 7-speed Freehub which can only be used with 7S cassettes unless you do a "8 of 9 on 7" thing where you use 8 cogs of a 9 speed cassette on your 7S body.

The current "standard" Shimano Freehub body works with 8, 9, or 10S cassettes. Realize if you go to any of these you'll need new shifters and chain at the very least, and of course the proper cassette and Freehub body or new rear wheel.

I would leave it at a new 7S cassette and chain and call it a day.

I can't see going to 9 or 10 spd., but it seems I'll have to move on from 7 spd. at some point given the ever limited options for maintaining it. The conclusion I've reached is that since my recent purchase of the 7 spd cassettes gives me at least another couple of years (prob'ly more), I can decide what to do at that point: new rear wheel/hub (along with chain/shifter) or new bike. For now, I can just get back to riding :)

Cheers...Steph

And keep an eye on your chains from now on! ;)

That's what I've been thinking. I've got a similar Hardrock with a 7 speed cassette on it that I just discovered could be converted to a 9 speed cassette. I upgraded the rd a few years ago to a Shimano that can handle up to 9 speeds, but figured I'd just go to 8 if and when I do it due to the lower maintenance and costs of the 8 speed parts. Especially when I only would want to narrow the gap between 2 gears anyway.

FWIW, I just build up a MTB for myself with a 7-speed rear because I already had the wheelset and some old school Deore 7S thumbshifters laying around. I'm using a 7S 12-32 SRAM cassette and 6/7/8 chain. The rest of the parts are actually "9 speed" (both derailers and Deore external bearing crankset) but everything works just fine together.

Thought I'd circle back around on this......

Recv'd my new cassettes (HG30, 7 spd.). I thought I had an HG50 on the bike. When I went to replace the worn cassette, I took a look at the model. Turns out it was an HG60 7 spd. (Had originally ordered an HG70 7spd. but Performance Bike delivered an HG60, never told me and I had to ask for a refund difference).

I looked to see how much difference there was between the 2 cassette. Both appear to be nickel-plated (tho, I can't tell what metal alloy is underneath). The obvious difference is that the HG60 was designed to be lighter...there was a lot of metal missing between the teeth and the spline/Freehub mount. The HG30s I bought have a lot of the metal still there, so I assume it weighs a bit (and then some) more.

I don't mind the weight. 50 or 60 grams won't make much of a difference since my bike is a steel frame and I don't spend a lot of time climbing mts. What I don't know is how durable this low-end model cassette is. Guess I'll find out :) Like I mention above, if I get 3-5 years out of both of them (assumes I keep a closer eye on the chain 8^( I should be ready to decide: new rim or new bike...

Cheers....Steph