BikeRider22

Dear Experts,

I have a Surly Cross Check with Truvativ cranks
2 * 8
34, 50 teeth front
110 BCD
5 bolt holes
Phil Wood bottom bracket

See the images.

...

Mostly, I use the small chainring.
It's rare for me to use the large chainring
these days.

As I get older, I find my legs don't have
strength that I did in my twenties.

I've noticed with this bike (not just these cranks)
that the chain has a bad habit
of just falling off the inner chainring.
Often enough to make me swear.

So I've been looking for some hardware to
install, to keep the chain in place.

I've seen on other types of bikes,
especially those with only a single chainring,
both inner, and outer chainguards.





To be continued.
More posts/images to come

BikeRider22

...

There are the Bashguards from
https://bbgbashguard.com/

There are some images with road bikes, and two chainrings.
But, only the outer chainring.

BikeRider22

There is the
Truvativ 36t Lightweight BashGuard 4 Bolt 104 BCD Mountain Bike Chainring Guard
https://www.ebay.com/itm/185379236366

But wrong size at 104.
Seems outer chainring only

BikeRider22

...


From China, there is the
Anti-Drop Bike Bicycle Chain Guide Holder Keeper Retainer for Single Speed
https://www.ebay.com/itm/254440913952
Again, only for single Speed

BikeRider22

...


There is the
OMNI Racer WORLDS LIGHTEST Chain Drop Catcher Fits Dura Ace Ultegra Sram:
https://www.ebay.com/itm/373618532929

Although, this bolts into the same holes used for
bolt on front derailleurs. But my front derailleur
is an old style hinged clamp on. So, no bolt hole.

BikeRider22

...

From Blackspire, there is the Cyclocross Bashring
130/135/110 BCD
https://www.blackspire.com/product/c...130135110-bcd/

But for Single-Chainring Cyclocross bikes

BikeRider22

...

There is
Shimano Alfine S501 Chain Guards
https://www.universalcycles.com/shop...s.php?id=72211

But
Wrong BCD
And, seems only for single chainring, outer

BikeRider22

q1:

So, does anyone know of some hardware that I could
mount on, or near, the inside/smaller crank,
to stop the chain from falling off?

Thanks

Crankycrank

First off have you tried adjusting the limit screw on the derailleur? If that hasn't worked I can't recommend a specific version for your bike but you need to know if you have a band-on front derailleur or braze on mount which will narrow it down to what you can use. For instance the one in post #5 you'll need a braze on derailleur mount to bolt it to but many band-on type catchers will also work with braze on frames as long as you have enough clearance for the band. You're looking for "Chain Catchers" bicycle chain catchers - Search (bing.com) No need to buy the most expensive either.

HillRider

There are several "chain checkers" that clamp onto the seat tube to prevent the chain from derailing to the inside. The Third Eye makes one called the "Chain Watcher" and Amazon and your bike shop should have them There is also the N-gear "Jump Stop" which does the same job.

70sSanO

You should not be dropping a chain off the inner chainring if you are not down shifting. You shouldn’t regardless. If it happens when you are shifting adjusting the limit screws, derailleur height and angle might help.

Every now and then there is a combination that won’t co-operate. I have used an N-gear Jump Stop and that works well to guide the chain back onto the chainring. I’m not sure if they are still around, but they pop up on eBay from time to time.

The cleanest approach is to run a triple cranskset and use the outer and middle positions with a chainguard in the inner position. This will take a bit of figuring out the spacing between the middle and inner and the diameter. If you go this route you need to be aware of chainstay clearance and middle-big cog angle.

With a 2x8, you should decide if you get enough range with a 34t or 36t chainring to go to a 1x. I would think a 1x9 might be a better direction. The cassette you are running will play a big part in that.

If you decide to run just the inner chainring, I think you can go to a narrow-wide and remove your FD, no need to trim.

John

bboy314

Another vote here for the third eye chain watcher.

cranky old road 

Deda Dog Fang not currently available on Amazon

Iride01 

Chain shouldn't be dropping at all. So instead of buying a band aid solution, you should figure out why it's dropping.

Which cogs on the rear are you in normally when the chain drops? Are you shifting at the time it drops?

oldschoolbike

I am with "cranky old road" on this. The Dog Fang seems to be the tidiest solution, and I will get one at the first sign of trouble with my new 46/30 setup.

https://www.chainreactioncycles.com/...r/rp-prod84217

The "size" referred to is seat tube diameter in mm.

oldschoolbike

BikeRider22

Thanks all for the good suggestions

The third eye looks useful
https://www.bikeradar.com/reviews/co...atcher-review/

Interestingly, here is a webpage just of

Bicycle Chain Deflectors
https://www.modernbike.com/chain-deflectors

BikeRider22

BTW, when the chain comes off,
it's not when I'm shifting.

When the chain comes off, it's usually when I
carry the bike down the stairs,
then maneuver through the two doors.

Then just when I'm ready to hop on the bike,
the chain is off. When it was perfectly
mounted a minute earlier.

When I carry the bike, I'm not pedaling it forward.

So maybe it's coming off from the bottom, and
some kind of backpedal.

Very disobedient.

Go figure.

BikeRider22

Info on n-gear here:

Instruction Sheet

https://www.bothybikes.co.uk/m9b49s2...Gear-Jump-Stop

BikeRider22

Article on chain drops on the Sheldon Brown website

https://sheldonbrown.com/chain-drop.html

Including a cyclocross ring and a chain guide

Kapusta

A whole lot of peoples’ time spent giving advice would have been saved have you given this obviously relevant info to start with.

Trakhak

Chain watchers, etc., are probably not going to help if the chain is unshipping when you carry the bike. Me, I'd just shift into the big ring as I end my ride. The additional spring tension from the rear derailleur should keep the chain in place for the next ride.