help with changing a chainring please
#1
Newbie
Thread Starter
Join Date: Mar 2014
Posts: 3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
help with changing a chainring please
hi,
I'm new to servicing my bike. I've always let the shop do it but I have decided that I needed more frustration in my life so here I am!
I have worn components and need to change my chain and a couple of chainrings on a shimano triple FC4603 crankset. I'd blush if I had to admit how much reading I've had to do to even come up with the basic plan here....
my question is this....do I have to remove the crank to replace the middle chainring on this unit?
It seems to me that I do. I can get the outer/larger 50 tooth ring off no prob of course but the middle seems to have to come off from the back which would require removing the crank. Here is the spec for the unit I need to service:
https://techdocs.shimano.com/media/te...9830746319.pdf
I'm asking this in case there is some trick I can't see.
thanks
-Conor
I'm new to servicing my bike. I've always let the shop do it but I have decided that I needed more frustration in my life so here I am!
I have worn components and need to change my chain and a couple of chainrings on a shimano triple FC4603 crankset. I'd blush if I had to admit how much reading I've had to do to even come up with the basic plan here....
my question is this....do I have to remove the crank to replace the middle chainring on this unit?
It seems to me that I do. I can get the outer/larger 50 tooth ring off no prob of course but the middle seems to have to come off from the back which would require removing the crank. Here is the spec for the unit I need to service:
https://techdocs.shimano.com/media/te...9830746319.pdf
I'm asking this in case there is some trick I can't see.
thanks
-Conor
#2
Member
Join Date: May 2005
Location: Brussels, Belgium
Posts: 31
Bikes: specialized hemi, Cannondale trail 5 29er, and Dahon Vitesse
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
You don't have to remove the crank.
The middle chainring is attached with the same bolts as the large one.
Just remove the large chainring and you will see.
The middle chainring is attached with the same bolts as the large one.
Just remove the large chainring and you will see.
#3
Senior Member
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 38,658
Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
Mentioned: 140 Post(s)
Tagged: 1 Thread(s)
Quoted: 5762 Post(s)
Liked 2,537 Times
in
1,404 Posts
+1, the inner ring's diameter is too small, and cannot be removed over the mounting arms (aka spider), but the middle can easily be maneuvered over one arm at a time, and a new one mounted the same way.
When installing the replacement, be sure to keep the inside in, and outside out. Usually it's easy because the inner (toward the bike) surface has counterbores to recess the nuts of the mounting bolts.
BTW- you may need a chainring nut wrench (or may not) to hold the nut while you turn the bolt with a 5mm hex or torx key. The nut wrenches aren't always needed, but can be if the crank's old and there's rust or corrosion in the threads.
When installing the replacement, be sure to keep the inside in, and outside out. Usually it's easy because the inner (toward the bike) surface has counterbores to recess the nuts of the mounting bolts.
BTW- you may need a chainring nut wrench (or may not) to hold the nut while you turn the bolt with a 5mm hex or torx key. The nut wrenches aren't always needed, but can be if the crank's old and there's rust or corrosion in the threads.
__________________
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
Last edited by FBinNY; 03-26-14 at 04:59 PM.
#4
Senior Member
Join Date: Oct 2007
Location: West Yorkshire, United Kingdom
Posts: 5,773
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 453 Post(s)
Liked 104 Times
in
87 Posts
With an HT2 crank, the process for removing the crank is so quick and simple, it makes little sense to leave the crank on the bike if attempting to remove the middle or outer rings.
Removing the crank would also allow you to clean any debris in-between the crank arms and BB which is normally pretty inaccessible, and will avoid any potential scratching of the arms on the chainring removal/install.
Removing the crank would also allow you to clean any debris in-between the crank arms and BB which is normally pretty inaccessible, and will avoid any potential scratching of the arms on the chainring removal/install.
#5
Newbie
Thread Starter
Join Date: Mar 2014
Posts: 3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
great! thanks for the replies. I'm ordering the parts and will give it a go so. Something tells me you haven't heard the last of me
#6
Senior Member
Join Date: Apr 2009
Location: New Rochelle, NY
Posts: 38,658
Bikes: too many bikes from 1967 10s (5x2)Frejus to a Sumitomo Ti/Chorus aluminum 10s (10x2), plus one non-susp mtn bike I use as my commuter
Mentioned: 140 Post(s)
Tagged: 1 Thread(s)
Quoted: 5762 Post(s)
Liked 2,537 Times
in
1,404 Posts
Is that a threat? (maybe it's a treat)
__________________
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
FB
Chain-L site
An ounce of diagnosis is worth a pound of cure.
Just because I'm tired of arguing, doesn't mean you're right.
“One accurate measurement is worth a thousand expert opinions” - Adm Grace Murray Hopper - USN
WARNING, I'm from New York. Thin skinned people should maintain safe distance.
#7
Senior Member
Join Date: Jan 2010
Location: Wahiawa. Oahu
Posts: 1,701
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
The trick you can't see is that the bolts attaching the rings to the spider are super tight. Whether or not you take the crankset off the bike to do the changeover, you might want to consider loosening the bolts (Breaking them loose) while the cranket is still installed on the bike, as this configuration gives you much more stability and leverage. Same with final tightening after you're done.
#8
Senior Member
Join Date: Aug 2005
Location: Pittsburgh, PA
Posts: 33,656
Bikes: '96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '20 Surly Midnight Special, All are 3x10. It is hilly around here!
Mentioned: 39 Post(s)
Tagged: 0 Thread(s)
Quoted: 2026 Post(s)
Likes: 0
Liked 1,095 Times
in
741 Posts
One specific with the FC-4603 crank is that the 30T granny chainring is bolted to the middle 39T chainring, not to a separate bolt circle. So, to remove the middle chainring without pulling the crank, the granny ring must be unbolted from it first.
#9
Newbie
Thread Starter
Join Date: Mar 2014
Posts: 3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
great guys. thanks. components are in work so must see can I get them tomorrow and give this a go.
...and no that wasn't a threat (unless you are sick of me already ..... in which case I guess it was!)
...and no that wasn't a threat (unless you are sick of me already ..... in which case I guess it was!)
#11
Senior Member
Join Date: Feb 2004
Location: St Peters, Missouri
Posts: 30,225
Bikes: Catrike 559 I own some others but they don't get ridden very much.
Mentioned: 16 Post(s)
Tagged: 0 Thread(s)
Quoted: 1572 Post(s)
Liked 643 Times
in
364 Posts
The trick you can't see is that the bolts attaching the rings to the spider are super tight. Whether or not you take the crankset off the bike to do the changeover, you might want to consider loosening the bolts (Breaking them loose) while the cranket is still installed on the bike, as this configuration gives you much more stability and leverage. Same with final tightening after you're done.
__________________
My greatest fear is all of my kids standing around my coffin and talking about "how sensible" dad was.
My greatest fear is all of my kids standing around my coffin and talking about "how sensible" dad was.
Thread
Thread Starter
Forum
Replies
Last Post
klxdrt
Folding Bikes
1
03-17-10 02:25 PM