Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 08-12-17, 06:21 AM   #1
BikingViking793
Junior Member
Thread Starter
 
Join Date: Aug 2017
Bikes:
Posts: 15
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Road Bike - First broken spoke

So this morning for no obvious reason I broke a spoke. Don't remember anything in particular happening, just wheel was suddenly out of true. Is that normal for a spoke to go that way?

Now that I have a broken spoke I guess my best option is to bring to the shop? Replacing a spoke looks pretty easy, but I don't have a truer. How should I bring the wheel in? Should I just bring the whole bike? Should I just bring the wheel? Should I remove the tire? Will this be a quick repair for a shop or will it take days? Approximately how much should this repair cost? Thanks in advance for any info. It is my rear wheel btw.
BikingViking793 is offline   Reply With Quote
Old 08-12-17, 06:48 AM   #2
Richard8655
Senior Member
 
Join Date: Aug 2007
Location: Chicago suburbs
Bikes: 2007 & 2008 Specialized Tricross Comp
Posts: 227
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
If you have a reliable bike shop and don't have the tools or lots of exprience, I'd just take it in to them. It shouldn't cost that much. Mine were just trued by my LBS for about $30 done on the same day. Unless you want to become proficient and spend time on this.

I'd bring the whole bike in as they can make sure everything works well together.
Richard8655 is offline   Reply With Quote
Old 08-12-17, 06:54 AM   #3
HillRider 
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Bikes: '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
Posts: 30,138
Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 593 Post(s)
Is this wheel on a road bike or MTB. How many miles on this wheel? How heavy are you? Do you ride harshly (jump curbs, etc.)? Is this a low spoke count wheel?

Unless they have been obviously damaged, spokes do break with no prior warning as it's usually a fatigue failure. For the first broken spoke, have it replaced and hope it was an unusual event. If you break a second one, start thinking about a new wheel or having that one completely respoked. If you break a third one, have the wheel rebuilt.

If you want a fast turn around at the LBS take in just the bare wheel with the tire removed. How long the job will take depends on the work load at the LBS and how good a customer you are so a phone call to ask would be worth while. The cost should be fairly low unless this is an exotic wheel.
HillRider is offline   Reply With Quote
Old 08-12-17, 07:05 AM   #4
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
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
Posts: 35,079
Mentioned: 101 Post(s)
Tagged: 1 Thread(s)
Quoted: 3453 Post(s)
Yes, it's normal for spokes to break without an immediate cause. They break because of metal fatigue, which results from millions of flex cycles over time. It's just a reminder that the wheel is older, but likely has plenty of life left.

If you're comfortable with the basics like fixing a flat, remove the tire and bring just the wheel in. That should lower the cost by roughly the charge to install a tube.

Some shops will fix it while you run another errand, others will want to schedule it. Bringing just the wheel increases the odds of a quick turn around, since it reduces the time involved, and doesn't involve using the repair stand.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

“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.
FBinNY is offline   Reply With Quote
Old 08-12-17, 01:59 PM   #5
Bill Kapaun
Senior Member
 
Bill Kapaun's Avatar
 
Join Date: Feb 2007
Location: Mid Willamette Valley, Orygun
Bikes: 86 RockHopper,2008 Specialized Globe. Both upgraded to 9 speeds.
Posts: 10,103
Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 394 Post(s)
Assuming the wheel was true to begin with-
Just replace the one spoke yourself and tension it enough to make the wheel true again.
Bill Kapaun is offline   Reply With Quote
Old 08-12-17, 07:53 PM   #6
BikingViking793
Junior Member
Thread Starter
 
Join Date: Aug 2017
Bikes:
Posts: 15
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Thanks guys. I brought it in and got it fixed, cost $16. Bike is ready to go now. Not sure if I will have more issues though. Only 400 miles on the bike.
BikingViking793 is offline   Reply With Quote
Old 08-12-17, 08:11 PM   #7
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
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
Posts: 35,079
Mentioned: 101 Post(s)
Tagged: 1 Thread(s)
Quoted: 3453 Post(s)
Quote:
Originally Posted by BikingViking793 View Post
Thanks guys. I brought it in and got it fixed, cost $16. Bike is ready to go now. Not sure if I will have more issues though. Only 400 miles on the bike.
400 miles to a spoke break isn't good news.

A single broken spoke may simply be a fluke or spot of bad luck, or it may be a harbinger of what's to come There's no way to know, but if/when you break another that may give you some insights. Generally the time interval between broken spokes gets progressively shorter.

So, if it was 400 miles to the first, and you break another in less than another 400 miles, then you can expect the 3rd in a yet shorter interval, and at that time may want to think about a new wheel rather than get to where you're spending $16.00 every hundred or so miles.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

“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.
FBinNY is offline   Reply With Quote
Old 08-12-17, 09:43 PM   #8
BikingViking793
Junior Member
Thread Starter
 
Join Date: Aug 2017
Bikes:
Posts: 15
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Quote:
Originally Posted by FBinNY View Post
400 miles to a spoke break isn't good news.

A single broken spoke may simply be a fluke or spot of bad luck, or it may be a harbinger of what's to come There's no way to know, but if/when you break another that may give you some insights. Generally the time interval between broken spokes gets progressively shorter.

So, if it was 400 miles to the first, and you break another in less than another 400 miles, then you can expect the 3rd in a yet shorter interval, and at that time may want to think about a new wheel rather than get to where you're spending $16.00 every hundred or so miles.
My bike has Weinmann TR28 rims and 14g spokes.

I don't know anything about wheels yet, is there any reason to believe these wouldn't be a very good wheel. It's on a very entry level road bike (Nikishi Maricopa). The shop seemed to think the wheels were ok, but mentioned the spokes were nickel? Which I assumed was nickel plated.
BikingViking793 is offline   Reply With Quote
Old 08-12-17, 10:00 PM   #9
FBinNY 
Senior Member
 
Join Date: Apr 2009
Location: New Rochelle, NY
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
Posts: 35,079
Mentioned: 101 Post(s)
Tagged: 1 Thread(s)
Quoted: 3453 Post(s)
Quote:
Originally Posted by BikingViking793 View Post
My bike has Weinmann TR28 rims and 14g spokes.

I don't know anything about wheels yet, is there any reason to believe these wouldn't be a very good wheel. It's on a very entry level road bike (Nikishi Maricopa). The shop seemed to think the wheels were ok, but mentioned the spokes were nickel? Which I assumed was nickel plated.
The spokes are OK. They're carbon steel, similar to piano wire, and should last until rust gets to them.

Spoke life is a complicated thing, and premature spoke breakage (IMO, all spoke breakage is premature) can from causes relating to the wheel build, ie. too little, too much or uneven tension.

It can also be related to the rider. Some riders tend to have bad luck with wheels, while others never have issues. Things like standing and letting the bike float over bumps and potholes, keeping the bike vertical under you, and a smooth pedaling style make a big difference. In my years I've known ballerinas who rode like gorillas, and gorillas who rode like ballerinas, so as you go forward think abut your part in this.
__________________
FB
Chain-L site

An ounce of diagnosis is worth a pound of cure.

“Never argue with an idiot. He will only bring you down to his level and beat you with experience.”, George Carlin

“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.
FBinNY is offline   Reply With Quote
Old 08-12-17, 10:32 PM   #10
europa
Grumpy Old Bugga
 
europa's Avatar
 
Join Date: Oct 2006
Location: Adelaide, AUSTRALIA
Bikes: Hillbrick, KHS Flite 500, Europa (R.I.P.)
Posts: 3,936
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 259 Post(s)
It is not unusual for a spoke to break in a new wheel, particularly low end wheels like yours. This is because they are nearly all built by machines and the spoke tension varies around the wheel. A good shop will retension new wheels before they're sold which goes a long way towards preventing breakages but not all shops will do it will do it for all bikes.

Now that you've had a breakage, keep an eye on things because you may have other spokes about to go.

A properly tensioned wheel will go for a long long time without any truing or spoke breakages. Your bike shop would have checked this out in the repair so you should be right from now on. I've only had one wheel that refused to behave and that was hand built, but I've always suspected the drive side spokes were too short (sold the sod now)
europa is offline   Reply With Quote
Old 08-13-17, 11:34 AM   #11
BikingViking793
Junior Member
Thread Starter
 
Join Date: Aug 2017
Bikes:
Posts: 15
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Quote:
Originally Posted by europa View Post
It is not unusual for a spoke to break in a new wheel, particularly low end wheels like yours. This is because they are nearly all built by machines and the spoke tension varies around the wheel. A good shop will retension new wheels before they're sold which goes a long way towards preventing breakages but not all shops will do it will do it for all bikes.

Now that you've had a breakage, keep an eye on things because you may have other spokes about to go.

A properly tensioned wheel will go for a long long time without any truing or spoke breakages. Your bike shop would have checked this out in the repair so you should be right from now on. I've only had one wheel that refused to behave and that was hand built, but I've always suspected the drive side spokes were too short (sold the sod now)
Thanks. So if I'm following you, maybe the spoke that broke was tighter than the others so it was more likely to break? Do most just feel spoke tension, or is a spoke tension meter really needed? They aren't so cheap.
BikingViking793 is offline   Reply With Quote
Old 08-13-17, 11:57 AM   #12
berner
Senior Member
 
Join Date: May 2010
Location: Bristol, R. I.
Bikes: Specialized Secteur, old Peugeot
Posts: 2,882
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 149 Post(s)
Quote:
Originally Posted by BikingViking793 View Post
Thanks. So if I'm following you, maybe the spoke that broke was tighter than the others so it was more likely to break? Do most just feel spoke tension, or is a spoke tension meter really needed? They aren't so cheap.
I've learned to true my own wheels. This was very frustrating at first but in general I enjoy messing with equipment. I don't have a truing stand either so truing takes longer than a pro in a well equipped shop. I turn the bike upside down and spin the wheel while holding a felt tip pen against the rim with the hand resting against some part of the frame. The pen will leave a black mark on every high spot. While turning nipples I also pluck the spokes so that they all sound the same indicating equal tension. At the same time, it is necessary to keep an eye out so that the wheel is centered in the frame. This may sound complicated but it is not really and the wheel can be brought to true within 1/2 mm or so. At this point the felt tipped pen will leave a streak almost everywhere on the rim.
berner is offline   Reply With Quote
Old 08-13-17, 11:58 AM   #13
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 8
Posts: 27,966
Mentioned: 60 Post(s)
Tagged: 0 Thread(s)
Quoted: 2855 Post(s)
bring whole bike presuming it was not bought at a bikeshop and so checked over as it was assembled, for adequate spoke tension..

cold have come from a place like WallyWorld, where people don't know enough to realize the fork is backwards in the shipping carton.
to fit, but should not stay that way..
fietsbob is offline   Reply With Quote
Old 08-13-17, 12:25 PM   #14
velocentrik
Senior Member
 
Join Date: Sep 2015
Location: Front Range, Colorado
Bikes:
Posts: 126
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 71 Post(s)
Quote:
Originally Posted by europa View Post
It is not unusual for a spoke to break in a new wheel, particularly low end wheels like yours. This is because they are nearly all built by machines and the spoke tension varies around the wheel. A good shop will retension new wheels before they're sold which goes a long way towards preventing breakages but not all shops will do it will do it for all bikes.
I
Now that you've had a breakage, keep an eye on things because you may have other spokes about to go.

A properly tensioned wheel will go for a long long time without any truing or spoke breakages. Your bike shop would have checked this out in the repair so you should be right from now on. I've only had one wheel that refused to behave and that was hand built, but I've always suspected the drive side spokes were too short (sold the sod now)
+1

Good bike shops are few and very far in between. Good bike shops used to rebuild all new bike wheels out of the box to bring them to even a balance of even tension and radial and lateral true. Finding the sweet spot of a given selection of rim, spoke, nipple, tension isn't something that usually can be done "one-off". Essentially it's a balance of trying to bring the wheel up to the highest tension it can handle without tacoing, or pulling spokes through the rim, excessively.

Sounds like the shop you bought the bike from unpacks new bikes from the box puts them together and sells them "as-is" new. If you took the bike back to the same shop you bought it from with less than 400 miles on the bike AND they charged you to repair the broken spoke you learned a valuable lesson: Never go to that shop again
velocentrik is offline   Reply With Quote
Old 09-04-17, 07:42 AM   #15
BikingViking793
Junior Member
Thread Starter
 
Join Date: Aug 2017
Bikes:
Posts: 15
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Just broke another spoke. Closing in on 600 miles. Not sure what I should do now.
BikingViking793 is offline   Reply With Quote
Old 09-04-17, 07:58 AM   #16
HillRider 
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Bikes: '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
Posts: 30,138
Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 593 Post(s)
Quote:
Originally Posted by BikingViking793 View Post
Just broke another spoke. Closing in on 600 miles. Not sure what I should do now.
The wheel must have been very poorly built originally and the spoke tension was either way too low or way too high. At this point, cut your losses and replace the entire wheel with a high quality one.
HillRider is offline   Reply With Quote
Old 09-04-17, 10:49 AM   #17
BikingViking793
Junior Member
Thread Starter
 
Join Date: Aug 2017
Bikes:
Posts: 15
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Quote:
Originally Posted by HillRider View Post
The wheel must have been very poorly built originally and the spoke tension was either way too low or way too high. At this point, cut your losses and replace the entire wheel with a high quality one.
I'd be interested in any decent quality, yet affordable suggestions. I have the claris group set so needs to work with that.
BikingViking793 is offline   Reply With Quote
Old 09-04-17, 11:35 AM   #18
HillRider 
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Bikes: '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
Posts: 30,138
Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 593 Post(s)
Claris is one of Shimano's lower line groups. It is still 8-speed and comes on entry level road and hybrid bikes so it's safe to assume the wheels that accompany the bike are low cost, machine assembled and were not checked for tension or true by the bike shop.

Assuming the rims are 700c and the bike has caliper brakes, any decent 8/9/10-speed (130 mm dropout spacing) Shimano compatible freehub wheel will work. I don't know what you consider "aforable" but here is a complete (front and rear) Shimano wheel set for $110. I have these on my "rain bike" and they have thousands of trouble free miles:
Shimano WH-R501 Wheelset > Components > Wheels > Road Wheels | Jenson USA

Nashbar and Niagara Cycles also sell adequate quality wheel sets ar attractive prices.
HillRider is offline   Reply With Quote
Old 09-05-17, 01:54 PM   #19
Jon T
Senior Member
 
Join Date: Jun 2017
Location: West Orange County, CA
Bikes: '84 Peugeot PH10LE
Posts: 272
Mentioned: 4 Post(s)
Tagged: 0 Thread(s)
Quoted: 90 Post(s)
Learn to true your wheels. It isn't rocket science.
Jon
Jon T is offline   Reply With Quote
Old 09-05-17, 02:29 PM   #20
Jwoair23
Junior Member
 
Join Date: Apr 2017
Bikes:
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 7 Post(s)
Op - I have a Nishiki Maricopa and had the same issue. I just bought a set of Mavic CXP 22 wheels that come with continental tires and Claris hubs, they are 32 spoke and supposed to be very strong. They were $180 shipped. I might suggest going that route for peace of mind. I am at about 900 miles with this bike, and I absolutely love it for what I paid brand new ($380 on sale) but I think the wheels are not very good.
Jwoair23 is offline   Reply With Quote
Old 09-05-17, 07:54 PM   #21
BikingViking793
Junior Member
Thread Starter
 
Join Date: Aug 2017
Bikes:
Posts: 15
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Quote:
Originally Posted by HillRider View Post
Claris is one of Shimano's lower line groups. It is still 8-speed and comes on entry level road and hybrid bikes so it's safe to assume the wheels that accompany the bike are low cost, machine assembled and were not checked for tension or true by the bike shop.

Assuming the rims are 700c and the bike has caliper brakes, any decent 8/9/10-speed (130 mm dropout spacing) Shimano compatible freehub wheel will work. I don't know what you consider "aforable" but here is a complete (front and rear) Shimano wheel set for $110. I have these on my "rain bike" and they have thousands of trouble free miles:
Shimano WH-R501 Wheelset > Components > Wheels > Road Wheels | Jenson USA

Nashbar and Niagara Cycles also sell adequate quality wheel sets ar attractive prices.
Those do sound affordable. Just curious, I'm about 200 pounds. Should I expect them to be pretty solid or are you much lighter?
BikingViking793 is offline   Reply With Quote
Old 09-05-17, 07:57 PM   #22
BikingViking793
Junior Member
Thread Starter
 
Join Date: Aug 2017
Bikes:
Posts: 15
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 12 Post(s)
Quote:
Originally Posted by Jwoair23 View Post
Op - I have a Nishiki Maricopa and had the same issue. I just bought a set of Mavic CXP 22 wheels that come with continental tires and Claris hubs, they are 32 spoke and supposed to be very strong. They were $180 shipped. I might suggest going that route for peace of mind. I am at about 900 miles with this bike, and I absolutely love it for what I paid brand new ($380 on sale) but I think the wheels are not very good.
I was looking at those wheels. How many miles do you have on the wheels so far? On sale I got my bike for $420. They do seems like a good deal all things considered. Other than this spoke issue it has been a good bike.
BikingViking793 is offline   Reply With Quote
Old 09-05-17, 08:49 PM   #23
HillRider 
Senior Member
 
Join Date: Aug 2005
Location: Pittsburgh, PA
Bikes: '''96 Litespeed Catalyst, '05 Litespeed Firenze, '06 Litespeed Tuscany, '12 Surly Pacer, All are 3x8,9 or 10. It is hilly around here!
Posts: 30,138
Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 593 Post(s)
Quote:
Originally Posted by BikingViking793 View Post
Those do sound affordable. Just curious, I'm about 200 pounds. Should I expect them to be pretty solid or are you much lighter?
I'm somewhat lighter but the wheels are very solid and properly adjusted when I got them. I have 700x28 tires on them and they add a bit of cushioning and reduce shock to the rims.
HillRider is offline   Reply With Quote
Old 09-06-17, 02:30 AM   #24
Jwoair23
Junior Member
 
Join Date: Apr 2017
Bikes:
Posts: 6
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 7 Post(s)
Quote:
Originally Posted by BikingViking793 View Post
I was looking at those wheels. How many miles do you have on the wheels so far? On sale I got my bike for $420. They do seems like a good deal all things considered. Other than this spoke issue it has been a good bike.
I have about 90 miles on them so far, I really like them. I am 6'2" about 195lbs so I wanted a very strong wheel front and back, and these fit the bill nicely from what I read with the high spoke count.
Jwoair23 is offline   Reply With Quote
Old 09-06-17, 08:09 AM   #25
cyccommute 
Mad bike riding scientist
 
cyccommute's Avatar
 
Join Date: Nov 2004
Location: Denver, CO
Bikes: Some silver ones, a red one, an orange one and a few titanium ones
Posts: 19,308
Mentioned: 38 Post(s)
Tagged: 1 Thread(s)
Quoted: 1140 Post(s)
Quote:
Originally Posted by BikingViking793 View Post
I was looking at those wheels. How many miles do you have on the wheels so far? On sale I got my bike for $420. They do seems like a good deal all things considered. Other than this spoke issue it has been a good bike.
From your other post, I gather that the bike is new. If that's the case, this should be a warrantee issue. Most likely the wheels needed a final tensioning and that wasn't done. You shouldn't have to deal with broken spokes on a bike that has as low a mileage on it as yours appears to have.

Bottom line: If the bike is new, the manufacturer should be buying you new wheels. You shouldn't have to.
__________________
Stuart Black
New! Pokin' around the Poconos A cold ride around Lake Erie
New! Dinosaurs in Colorado A mountain bike guide to the Purgatory Canyon dinosaur trackway
Solo Without Pie. The search for pie in the Midwest.
Picking the Scablands. Washington and Oregon, 2005. Pie and spiders on the Columbia River!
Days of Wineless Roads. Bed and Breakfasting along the KATY
Twisting Down the Alley. Misadventures in tornado alley.
An Good Ol' Fashion Appalachian Butt Whoopin'.
cyccommute is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 04:19 AM.


 
  • Ask a Question
    get answers from real people!
Click to start entering your question.
I HAVE A QUESTION