Replace crankset 7 speed square taper



xar1540

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Sep 30, 2006
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I'm looking at replacing my STX triple 22 32 42 175mm crankset soon. It has a 94 BCD (22 ring is ok) so i'm looking for a crank with the more common 110BCD.

Is the Sugino XD-600 the only option apart from the low end current model Acera Shimano?

https://www.amazon.com/Sugino-175mm-26-36-46-74-110-7-8-Speed/dp/B001GSSE2Q

The Acera crankset is $48 and available locally, so no freight costs. The Sugino from memory is $125 with freight. I rather not ruin the look of my 1996 Trek with the Acera if possible.

http://www.cellbikes.com.au/Shimano-Acera-T3010-Crankset-48-36-26

SJS cycles in the UK has NOS Deore XT square taper cranks for $160, but by the time i add chainrings and freight to Australia it will be just too expensive.

https://www.sjscycles.co.uk/cranks/shimano-deore-xt-fcm730-11074-pcd-crankset-silver-175-mm/?geoc=AU
 
Despite having a square taper, 99.9% of the SUGINO cranks which I have seen have an ISO taper ... which is slightly "smaller" than the JIS taper ...

The angle of the taper is the same, and you can sleeeve a Sugino crank on a JIS taper BB spindle, but the arms will sit about 5mm wider than they would if they were mounted on an ISO BB spindle of the same length.

A JIS (Shimano) square taper crankset will bottom out if you try to mount it on an ISO BB spindle.​

In other words, you will need to find an ISO (or example, Campagnolo or Sugino) BB spindle which has the appropriate length OR simply be aware that the arms will be slightly further apart after they are mounted.

BTW. SOME square tape cranks use asymmetrical spindles, some use symmetrical spindles.​

While there may be some advantages to using a crank with a square taper, I think that you may want to consider installing an FSA MegaExo crankset & BB cups as a replacement ...

FSA Mega Exo BB cups & Shimano Hollowtech II BB cups are interchangeable ...

So, if you have deep pockets, you could choose a Shimano Hollowtech II crankset & BB.​
 
Thanks again alfeng.

You had worried me for a while. I checked the Sugino square taper. It is JIS as is my 73mm W 110mm L BB. The BB may possibly need to be changed to 114 L.

Another possible option is to order 2 titanium or stainless alloy chainrings that can be made to order from the US with a 94 BCB. Definitely not the cheapest option but some say they will well outlive a aluminum crankring. Earlier accounts say the titanium is actualy softer so i'm not sure.

http://www.warhawkindustries.com/chainrings/5-bolt-94mm-bcd-chainring.html
 
It's good that you were able to verify the taper on your current BB spindle ...

The next caveat is that it appears that SRAM (?) has re-invented the micro-94BCD from being a 5-arm "micro" configuration to a 4-arm configuration; and, from what I recall about Warhawk from a dozen-or-so years ago, the odds are (without looking at their site) that the 94BCD chainring they are currrently selling will be the current 4-hole variant rather than the older 5-hole variant.

Regardless, let eBay be one of your possible sources ...
These look to be very lightly used ...


Even in the past few years, I considered buying a 90s vintage 5-arm XT crankset which has the 110BCD that you think you want to use going forward ... they certainly become available from time-to-time on eBay ... and perhaps, one should be your targeted future purchase. They typically are only available with a 175mm crankarm which may-or-may-not work for you.

My 90s (or, was it 80s?) vintage Campagnolo THRON (MTB) crankset (110BCD) mounts nicely on a "standard" asymmetric 113mm Shimano spindle ...

BTW. FSA's MegaExo cranks are most typically "black" ... but, polished ("silver") cranks were also available.in the past.
 
BTW. I am actually a fan of steel inner chainrings ... and, I may have been the only person ever to use a steel 39t chainring on a DuraAce crankset ...

However, there is probably zero reason to pony up for a stainless steel chainring unless it is for show bike because rust probably isn't going to be an issue unless you truly neglect your bike ...

Titanium chainrings? I think I might have one (a 22t granny chainring comes to mind) only because someone "gave" it to me a long-long time ago ... I probably wouldn't pay a premium for one.​
 
Thanks again alfeng. I bought this early 90's Deore LX crankset today on ebay for about $45 including postage. I cheated and sniped in the last 5 seconds with gixen.com.

It looks to me to be in almost original condition. I'll need a longer 122.5mm BB to replace my 110mm BB evidently.

http://www.ebay.com.au/itm/BICYCLE-...D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

Now need to find another for my brother who has a 90's MTB with STX RC 7 speed groupset. I'm thinking about this one from the same seller. It is hard to tell how good condition it is in from the photos though.

http://m.ebay.com.au/itm/BICYCLE-AL...2-SUIT-MOUNTAIN-BIKE-/122137465513?nav=SEARCH
 
FWIW ...

If you can wait, I think you may want to check the fit of the LX crankset on your current BB and compare how it fits on your bike to ensure that a 122.5mm spindle isn't too long ...

And also, to see if you will need a BB with a symmetrical-or-asymmetrical spindle.

ALSO, if (by chance) you are only going to use it as a compact Double, then you will probably not want the longer spindle ...

My thought is that if you are going to use the LX crankset as a Triple on a (steel?) Road frame, then you may want a 118mm spindle. The multitude of combinations with square taper BB spindles is THE reason that I suggest you test fit the LX crank on an existing spindle & assess ... and then, buy accordingly.

FYI. While NOT exactly the same, I found that I could use a Shimano 6503 (Octalink Triple) with a 112.5mm XTR spindle instead of the 118mm spindle which Shimano spec'd for the crankset on a steel frame Road bike; so, a shorter spindle can be OK.

I did find that the particular Shimano 6503 crank needed the 118mm spindle when used with the aluminum frame Touring bike that I had.
As far as the OTHER crankset, as you already know, it has a micro-compact spider ... fairly non-standard in its day (I'm going to say that the 4-arm 104BCD cranks quickly superseded the micro-compact cranks for people who wanted the smaller chainrings which were popular on MTBs); and so, even more of an oddity now.

Why not choose a crank similar to the one you will soon be receiving for your brother's bike, too?

You may want to look for something like this Suntour crankset in Oz:

 

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