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Kiss my Grits!
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115 Posts
Discussion Starter · #1 ·
I had a tough day today. Before I got back to my truck to find that I had been broken into, I torqued my chainring on the trail and had to walk the last 3 miles or so. I think that my chainring bolts must have wiggled loose, but in any case, on a short, not so steep climb, I roached my chainring.
 

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Drinking the Slick_Juice
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1,809 Posts
there my four bolt theory in play . i just made a comment on this on the paper or plastic thread right before I moved to this one . I sure there is noting really wrong with steal rings as long as there in the five bolt pattern
 

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Out spokin'
In cog? Neato!
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14,525 Posts
What a coincidence... it's a 4-bolt Surly.

Good luck with that and the truck break-in thing. Hope the bad days are behind you.

--Sparty

Edit::: Hey Nuck, I posted mine before I read yours. I agree. 4-bolt spiders were a step in the wrong direction by the bike industry. The industry changed things strictly for the sake of offering something "new"... but increasing the distance between strength points of chainrings only weakened the system... without making anything lighter in the process. Too bad us consumers are always demanding "something new," eh.
 

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Kiss my Grits!
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115 Posts
Discussion Starter · #5 ·
Big or small? What's best

Well, I have a four-bolt, so my question is:

Would it be better to keep going smaller with the rear ring, or go bigger with the front ring?

I think I am to blame for this debacle. I was running a 1/8 KMC chain, which I am throwing away and going back to a 3/32 Sram. Stretch, stretch, stretch every ride.

The chainring bolts loosened, but I put thread lock on them, so I am not taking much blame on their loosening.

The bike was making some noise, but I thought it was because of the chain loosening.

Bottom line, I think the chain was too wide for my set up and that caused the problems and I was too unattentive to recognize the issue before failure.

Penalty: 3-mile walk and $45 for a new chainring. The new chain I was going to buy anyway.
 

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Drinking the Slick_Juice
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1,809 Posts
Sparticus said:
What a coincidence... it's a 4-bolt Surly.

Good luck with that and the truck break-in thing. Hope the bad days are behind you.

--Sparty

Edit::: Hey Nuck, I posted mine before I read yours. I agree. 4-bolt spiders were a step in the wrong direction by the bike industry. The industry changed things strictly for the sake of offering something "new"... but increasing the distance between strength points of chainrings only weakened the system... without making anything lighter in the process. Too bad us consumers are always demanding "something new," eh.
well now we know ;) . You cant find many five bolt pattern cranks that are cheap anymore. I bought a nice set of Dotek cranks right before Dans Comp discontinued selling them for 29.99, now I cant find them anywhere. You would think that there are cheap but they have last 3 years without any incident( and I mash hard for a 200 pounder)
 

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Expert Crasher
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6,358 Posts
Wow - that sucks!
 

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Birthday Collector
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2,610 Posts
Think about the economies of scale... You build 5 million cranks a year, and remove one bolt from each one, at a nickel each... Five million nickels is a quarter million dollar savings a year. Just like the way that they make the electrical cords on toasters and small appliances only 2 feet long instead of 5 feet long. Saving 3 feet of cord on umpteen-million small appliances saves these companies a bundle, and some CEO probably got his $25 million bonus for increasing profits 2% because of this...
 

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SSolo, on your left!
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2,577 Posts
The thin Surly chainring, 1/8" chain (no, no!), loosening chainring bolts....you were bound to have problems. Back to 3/32" chain as you said, a thicker chainring, make sure the chainring bolts are steel too. :) Those Surly rings look nice but there is so little material between bolts as compared to many other SS rings and imo thier stainless steel alloy is too soft. Sorry to hear about your break-in too. Post up with your replacement setup.

ATBScott said:
Think about the economies of scale... You build 5 million cranks a year, and remove one bolt from each one, at a nickel each... Five million nickels is a quarter million dollar savings a year. Just like the way that they make the electrical cords on toasters and small appliances only 2 feet long instead of 5 feet long. Saving 3 feet of cord on umpteen-million small appliances saves these companies a bundle, and some CEO probably got his $25 million bonus for increasing profits 2% because of this...
Yup. :madmax:
 

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Birthday Collector
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2,610 Posts
Going with 1/8" rings will net you quite a bit better wear... I had a 33t ring (aluminum) on my SS that is 3 years old, almost constant riding, and still in rideable condition. Replaced with a new 32t (1/8") and hope to get about the same type of life out of it. ISuckAtRiding makes some nice stuff - got the ring from him. He is "out of service" at the moment, upgrading his shop to handle more volume, but in a few weeks he'll be back making goods again. Might be too long to go without the bike though...
 

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Ovaries on the Outside
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4,425 Posts
And that is why I use a five bolt crank. I keep an eye on craigslist and pick them up all the time. They will almost positively ruin blacked out color(?) schemes though.
 

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Registered
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918 Posts
I don't have an issue with 4 bolt although steel chainring nits are a must. I went from a 20 tooth in the back to a 19 and second ride I broke an alloy chainring nut and the rest of the ride kept sucking because my chain kept jumping off. Went home and tossed 4 new alloy nuts on and by the second ride broke another. Went back to steel one's and I've been a happy camper ever since. Also when to an 18 tooth and with steel still no breakage.
 

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Registered
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212 Posts
Did this to my surly chainring a few months back, switch back to alloy and have had no issues with chainring bolts coming loose since. The alloy ring might wear faster but I'm a big fan of dependability and didn't feel like going through the whole ordeal again.
 

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Chronic 1st-timer
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2,432 Posts
I hate to imagine the upcoming catastrophic results that await my WI ring, which has no bolts.
 

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Kiss my Grits!
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115 Posts
Discussion Starter · #19 ·
repair nearly complete

I went with a 38t (7075) Ethirteen chainring. The LBS only carries aluminum bolts and assured me that they are fine. I just need to check them after every ride for loosening. After a couple of checks that show no loosening, they should be tight forever.

I also went back to a Sram 8-speed, 3/32 chain. Everything looks good, but it sounds like firecrackers going off when I spin the cranks. The sounds seem to be coming from the rear cog, but I can't find the origin of the noise. the chain-line looks good, I plumb-bobbed it again to be sure. The rear hub seems good. The chain seems good. But put them altogether and it sounds like the 4th of July.

Any ideas?
 
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