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stratocaster142
09-02-2019, 09:23 PM
This winter I upgraded my entire drive chain (eTAP). Long story short, I lost 3 chainring bolts while riding apparently (in only 4 friggin' rides). This morning I taco'd my inner chainring from the force of getting going from a stop. It's a Force22 50/34 crankset. I think the outter might have a slight bend in it too.

My question is can I run these replacement parts?

Inner Ring - 34t (https://www.excelsports.com/main.asp?page=8&description=11%2DSpeed+Chainring&vendorCode=SRAM&major=1&minor=12)

Outter Ring - 50t (https://www.excelsports.com/main.asp?page=8&description=Red+11%2DSpeed+Chainring&vendorCode=SRAM&major=1&minor=12)

Bolts (https://www.excelsports.com/main.asp?page=8&description=Red+22+Chainring+Bolt+Set&vendorCode=SRAM&major=11&minor=10)

Mark McM
09-03-2019, 10:41 AM
Are the cranks the most recent Force 22 cranks (with a 3-bolt removable spider) or older Force cranks? The following comments apply to the more recent Force 22 cranks:

The referenced SRAM 34 tooth inner chainring will work with just about any 110 BCD crank. I'm pretty sure that the refererenced Red 50 tooth outer chainring will also work with the Force 22 compact crank. But the Red chainring bolt set will not work correctly with the Force 22 crank.

The Force 22 removable spider crank is different from the earlier Force crank and the current Red 22 crank. Although the Force 22 crank looks like a "hidden 5th arm crank", it actually uses a traditional spider, with a standard spider arm hidden behind the crank. The Red 50 tooth chainring appears to have a countersunk bolt hole in the position behind the crank arm, so it should work with the traditional chainring bolts on the Force 22 crank.

However, the referenced Red chainring bolt set is intended for use with hidden 5th arm cranks in which the chainring bolt screws directly into the back of the crank arm. This set has 4 traditional chainring bolts/nuts, plus a thru-bolt and spacers for screwing into the back of the crank arm. The Force 22 "hidden" bolt does screw into the back of the crank arm, but instead uses a standard bolt/nut set. Well, almost standard - the nut on the "hidden" bolt is knurled, so that a chainring nut tool is not required to keep it from turning when the bolt is tightened. If you still have the knurled nut (it typically doesn't fall out), you can use it with a standard (8mm thread) chainring bolt.

stratocaster142
09-03-2019, 10:51 AM
Does this help?

https://scontent-lga3-1.xx.fbcdn.net/v/t1.15752-9/69459918_687229481757389_1449704195732013056_n.jpg ?_nc_cat=106&_nc_oc=AQkAWZSBPoliVRxqM4waSgGk78lwam-66jHETYBAjZSpskpJ5bUzQOwO4oLNE27N3-o&_nc_ht=scontent-lga3-1.xx&oh=45c8ba63ac32a13307adbe32853d4051&oe=5DFEEE44

Mark McM
09-03-2019, 11:10 AM
That appears to be the GXP Force 22 cranks with removable 3-bolt spider. In which case it appears that the referenced chainrings should work. If the "hidden" bolt/nut is still intact than it can be re-used, and the other bolts/nuts replaced with the 4 "traditional" bolts/nuts from the referenced bolt set (or just about any other standard chainring bolts/nuts). If the "hidden" bolt is not intact, than you'll either need to get a knurled chainring nut, or you'll have to remove the spider (3 torx bolts) in order to install the chainrings with standard bolts/nuts.

stratocaster142
09-03-2019, 12:13 PM
Thanks so much for the input! Is there a better/different nut/bolt set you'd recommend over the one I referenced? Also, why would the Red chain ring be less expensive than the Force? Wouldn't you expect the opposite?

Force22 Chainring (no 50t in stock though) = $109 (https://www.excelsports.com/main.asp?page=8&description=Force+22+Outer+Chainring&vendorCode=SRAM&major=1&minor=12)

Different Red versions (https://www.excelsports.com/main.asp?page=7&major=1&minor=12#.filter-SRAM) Are difference between the $99 listed RED chainrings just color and which link carries the 50t vs 52&53t?

simonov
09-04-2019, 10:44 AM
Was the crank new when you got it? That's crazy to lose that many chainring bolts. I'm a SRAM user and across a bunch of bikes and a bunch of generations of cranks, I've never had even a single bolt come out.

stratocaster142
09-04-2019, 01:11 PM
Brand spanking new out of the box. I've never seen before and I've never touched those bolts on any bike I've owned. Of course I bought them 10months ago, but only have like 4 rides on them. I don't know if it's worth a call to SRAM.

stratocaster142
09-04-2019, 01:16 PM
Also, the hidden bolt is in tact. So it's 3 of 5 gone :)

Mark McM
09-04-2019, 01:26 PM
Thanks so much for the input! Is there a better/different nut/bolt set you'd recommend over the one I referenced? Also, why would the Red chain ring be less expensive than the Force? Wouldn't you expect the opposite?

Force22 Chainring (no 50t in stock though) = $109 (https://www.excelsports.com/main.asp?page=8&description=Force+22+Outer+Chainring&vendorCode=SRAM&major=1&minor=12)

Different Red versions (https://www.excelsports.com/main.asp?page=7&major=1&minor=12#.filter-SRAM) Are difference between the $99 listed RED chainrings just color and which link carries the 50t vs 52&53t?

These cranks use very standard 10mm (8mm thread) chainring bolts/nuts, so just about any standard double chainring bolts/nuts should work. SRAM makes a few different sets of these bolts/nuts if you want same-brand bolts, or you could use after-market color anodized bolts if you want more bling. The Red bolt set you referenced contain 4 standard chainring bolts/nut plus a through-bolt for the "hidden" bolt, so you could use your existing "hidden" bolt/nut and the 4 standard bolt/nuts from that set.

I looked at the chainrings on the Excel Sport web page, and it appears to me that the main difference beween the chainrings is cosmetic rather than functional. I don't know why the Force 22 chainring should be more expensive, other than it is less common (there is typically more availability of high-end model chainrings than lower-end model chainrings).

simonov
09-04-2019, 03:35 PM
Brand spanking new out of the box. I've never seen before and I've never touched those bolts on any bike I've owned. Of course I bought them 10months ago, but only have like 4 rides on them. I don't know if it's worth a call to SRAM.

Absolutely worth a call to them. That's nuts that they fell out of a new crank. Now, it's always possible that someone in the distribution chain did something like take the original rings off them while waiting for replacements for a build and lazily put it back together with new rings, but it's still worth a call to them. Or to the shop where you bought the crank (or bike). If I remember correctly, those bolts usually have a light thread locker on them, so it would be very odd for them to not be tight and secure from the factory. Something is amiss.

stratocaster142
09-04-2019, 04:06 PM
I called Excel Sports and they are going to file a claim and see what SRAM says. They gave me some good options, so I'm going to go that route.