Chainring replacement

schreef ...

What you need to know is how many bolts on the ring and measure the
distance between the centers of two adjacent rings. Thi sis the Bolt
Dead Center measurment. ...

BCD or Bolt Center Diameter

... some Sugino ring shave been discontinued and
will be impossible to find. I beleive they were 94mm by 4 bolts.

For which size about 50 different companies market chainrings ......

--
Regards,
Marten

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(TekBuf) wrote in message . com...
I have a Sugino Impel crankset. The middle chainring has a bent tooth
and cannot be straightened. I need to replace it. I dont see Sugino
chainrings when I look at the online catalogs. I know it is a 32
tooth ring. This is for a Gary fisher Joshua X0 mountain bike. How do
I buy a replacement ring? Can I put a Shimano chainring in there
without adverse affects? Are there good chainrings at a lower cost?
Any recommended sources? Can I replace this myself? Thanx.


If you have a riveted crankset then you cannot easily replace
individual rings. Looking at
http://shop.airbomb.com/site/intro.c...=37&SKU=CR8890 the Sugino
Impel is described as riveted so, unless yours is different, you
cannot readily remove individual rings. You need a new crankset.
Be sure to get one with replaceable chainrings as it gives much more
flexibility in adjusting gearing and maintenance in future.

You could file down the tooth to a sensible profile as an interim
measure. One low tooth won't hurt much - look at tooth profiles of
many chainrings and you will see odd low tooths to aid shifting - it
might even be better ;-)

If your rings are not riveted in place, but are fixed by sleeved hex
bolts then any ring that fits will work.

Rings are sold by numbers of arms on crank (4 or 5) and BCD or bolt
circle diameter of the fixing bolts. Remove the old ring and measure
the BCD and away you go.

I find it easiest to lay the old ring on a sheet of paper, and mark
the position of the bolt holes. I then use a compass to draw a circle
through them and measure that.

Sheldon Brown has tablulated distance between bolt hole centres for
different BCDs if you find that easier (see
http://www.sheldonbrown.com/gloss_bo-z.html).

Andrew Webster

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On Tue, 12 Aug 2003 11:10:05 +0000, Andrew Webster wrote:

(TekBuf) wrote in message
. com...
I have a Sugino Impel crankset. The middle chainring has a bent tooth
and cannot be straightened. I need to replace it. I dont see Sugino
chainrings when I look at the online catalogs. I know it is a 32 tooth
ring. This is for a Gary fisher Joshua X0 mountain bike. How do I buy a
replacement ring? Can I put a Shimano chainring in there without
adverse affects? Are there good chainrings at a lower cost? Any
recommended sources? Can I replace this myself? Thanx.


If you have a riveted crankset then you cannot easily replace individual
rings. Looking at
http://shop.airbomb.com/site/intro.c...=37&SKU=CR8890 the Sugino
Impel is described as riveted

My crank is also Sugino Impel, and is definitely not riveted.

--

David L. Johnson

__o | This is my religion. There is no need for temples; no need for
_`\(,_ | complicated philosophy. Our own brain, our own heart is our
(_)/ (_) | temple. The philosophy is kindness. --The Dalai Lama


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schreef ...
In article ,
says...
schreef ...

What you need to know is how many bolts on the ring and measure the
distance between the centers of two adjacent rings. Thi sis the Bolt
Dead Center measurment. ...

BCD or Bolt Center Diameter

... some Sugino ring shave been discontinued and
will be impossible to find. I beleive they were 94mm by 4 bolts.

For which size about 50 different companies market chainrings ......



Find me one, please.

Sorry, I remembered 94 mm as being the outer BCD of a bog standard
Compact crankset. It is, actually, but those have 5-arm rings. Are you
sure Sugino had a 94mm/4-arm?

Anyway, Sugino's Impel 100, 120 and 150 were riveted, the 280 and 300
models were 104/58 mm 4-arm models. Say the Sugino website at:
http://www2.odn.ne.jp/suginoltd/index.html
(you can choose the crankset models from the drop-down box in the left
upper-hand corner)

--
Regards,
Marten

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rec.bicycles.off-road is moderated by volunteers. To find help solving
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On 12 Aug 2003 11:10:05 GMT, Andrew Webster
wrote:
If you have a riveted crankset then you cannot easily replace
individual rings. Looking at

I've often wondered why it's viewed as impossible
to remove the rivets and replace them with bolts.

Although I concede that it's often impractical,
given the usual quality of riveted cranksets.

Andrew Webster
--
Rick Onanian

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