Dahon 1x drivetrains: chain keeps falling off to the outside
 

i have a 2007 Dahon Speed P8. it has a 1x8 drivetrain. when i first got the bike, there was a plastic chain guard attached to the 53 tooth chainring to keep the chain from falling off to the outside of the ring. that plastic chain guard has since cracked and fallen to pieces. now, i have to deal with the chain falling off of the chainring about once every couple of rides. it's not the end of the world, but still pretty annoying none-the-less.

the LBS dealer where i purchased the bike was unable to get a replacement. so i contacted dahon directly and they said they didn't have any chain guards available as replacements. WTF? this part was obviously sourced from some manufacturer somewhere in the known universe, why dahon doesn't want to allow its customers to be able to get replacements for parts that break on their bikes is completely beyond me. i mean, it makes ABSOLUTELY. NO. SENSE.

dahon rant aside, have any other dahon owners run into this problem? what other options are available to me to keep my chain from falling off to the outside of my chainring? i thought about investigating bash guards as one idea, but i can't find a bash guard anywhere on the web that will fit a 53 tooth ring with a 5-bolt 110mm BCD (all i could find was a 5-bolt 130mm BCD for rings that large).

Try contacting Thor. He's the magic man when it comes to parts for Dahons.

I have used the Driveline brand .. that worked well .. there are other sellers with other colors also..

BAM! that's exactly what i need.

if only it came in black. oh well, beggars can't be choosers.

thanks a ton for posting that, BruceMetras!

You mean like This One ? You could even paint a 'D' close up the 'U' and it's almost spelled Dahon..

damn you're good at finding this stuff.

thank you once again!

No problem.. I'm done with lunch now .. gotta' get back at it..

BikeFriday also has 53t Chainguard discs ,Oregon, so they don't have to be shipped
from TW individually..

^ bikefriday doesn't have any 53 tooth chainguards for a 5-bolt 110mm BCD, they only have 130mm BCD, just like 99% of the rest of the world. 110mm BCD is the hard to find stuff.

They denied it that fast, did you call and ask?

Florian Schlumpf also supplies chain guards in all sorts of sizes..
he dishes his, so no spacers are required.

you might also be able to adapt stuff like Paul's Downhill Chain guides,

They go over the chain like a front derailleur cage.. to keep it located..

Check your chainline , it being off may increase the tendency to pull off the chain.

no, i checked their website.

doesn't matter anyway, as BruceMetras already found exactly what i need on ebay.

Well, that's funny because I still have an old school square taper Sugino crankset that's a 5 bolt 110BCD with a chain guard from guess who -- Bike Friday off my old no longer owned New World Tourist. The five bolt 110BCD pattern is used on old style mountain crank set or touring triple. They might not sell this anymore since it was from the early to mid 90s model bike. 110 BCD was in fast retreat in the past, but thanks to Tyler Hamilton and the TDF which brought back the popularity of 110BCD in a form of a compact double. Plus the Sugino touring triple is 110/74BCD, but you are right as the 130BCD crank is more common than a 110BCD if you want to find a chain guard for it.

NB their website is not complete inventory of the Mfgr shop resources.

Also check the chain ring for damage (bent?) and wear (hooked teeth?), and the chain, rear sprockets and derailléur for wear. If you wear long pants when cycling, have a look at the inside of the right hand leg cuff near the ankle for signs of chewing. Pants often flap into the chainwheel, throwing off the the chain. If the derailléur pivots need lube, or the tension wheel is worn the symptom is often frequent de-railments as the rear mech doesn't keep the chain tension up.

In addition to the chain-ring guards, there are numerous other products to combat this common issue: 1, 2, 3, etc. It's always - always! - fun to bash Dahon, but seriously, you want to pay a no-value-added markup for an OEM to supply you an industry standard part?