solving front chain drop issue on Dahoon Vitesse d8
#1
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solving front chain drop issue on Dahoon Vitesse d8
This is a clear design fault on the Dahoon D8, I'm wondering if a narrow wide chainring will help.
I recently brought the bike for a bike/cycle tour through Europe, I was anticipating selling it on my return, but I've actually somewhat fallen for it, but there are two big failures in the design,
1. The break and gear cables routes are ridiculous- I've sorted that,
2. The chain comes off the front chain ring occasionally when on he biggest rear sprocket, not because of chain jump, but because the chain angle is too much.
Will a narrow wide chainring solve this? or does it just solve chain jump on rough terrain?
I've tried changing the spacing on the rear wheel by a few ml, but then it comes off on the smallest rear sprocket - it seems the chain angle range between biggest and smallest sprocket is to much for the chain ring.
any thoughts appreciated
I recently brought the bike for a bike/cycle tour through Europe, I was anticipating selling it on my return, but I've actually somewhat fallen for it, but there are two big failures in the design,
1. The break and gear cables routes are ridiculous- I've sorted that,
2. The chain comes off the front chain ring occasionally when on he biggest rear sprocket, not because of chain jump, but because the chain angle is too much.
Will a narrow wide chainring solve this? or does it just solve chain jump on rough terrain?
I've tried changing the spacing on the rear wheel by a few ml, but then it comes off on the smallest rear sprocket - it seems the chain angle range between biggest and smallest sprocket is to much for the chain ring.
any thoughts appreciated
#2
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Our Mu D8, with the same chain angle range, has never dropped its chain. Lots of 1X8 folders use a similar drivetrain without issue.
A Vitesse should be fitted with a Dahon factory chain guide.
Make sure your chainwheel is perfectly straight.
The bike should be fitted fit a quality 8-speed chain.
A Vitesse should be fitted with a Dahon factory chain guide.
Make sure your chainwheel is perfectly straight.
The bike should be fitted fit a quality 8-speed chain.
Last edited by tcs; 07-03-23 at 09:06 AM.
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Have you tried moving the chainring inwards by installing it on the inside of the crank arms? If so, the next steps would be a wide-narrow chainring and/or a chain guide. Also make sure your chain is not too long or short.
#5
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Some folders have chain keepers or retaining rings to keep the chain in place, my Birdy had a keeper, and when I removed it, the chain dropped a few times. Install a keeper, and that should take care of your problem. You can also tighten the tension screw on your derailleur a little, this will hold the chain more tightly against the chain ring.
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#7
Schwinnasaur
And in fact, a factory-stock Dahon Vitesse is equipped with an inner chain guide and an outer chainwheel disc. As everyone can see, on an unmodified factory bike there is no way that "the chain comes off the front chain ring occasionally". I encourage our OP to jump back in and try to further explain because it sure seems like the claim of "Dahon design fault" does not hold up to scrutiny.
If I were to continue to be a problem, I would first try to address it with a narrow-wide chainring. As it comes stock, the Zizzo is somewhat geared to low.
Last edited by Schwinnsta; 07-08-23 at 07:07 AM.
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In this thread, the OP claimed the rear wheel was respaced a few millimeters to the left which caused the chain to come off the small rear sprocket to the left. This is nonsensical.
In a concurrent post on Bicycle Mechanics, the OP claimed the chain came off the front chainring to the left. This means the chain passed through the gap between the chain guide and the chainwheel disc - a gap that is smaller than the chain is wide. THEN after magically getting past this small gap, the chain climbs up over the chainwheel disc to come off. This is also nonsensical.
I again ask the OP to rejoin the thread and explain.
#9
Schwinnasaur
Sorry the Zizzo didn't work out for you. As I said in post no. 2, my Dahon has been fine for the last 15 years.
In this thread, the OP claimed the rear wheel was respaced a few millimeters to the left which caused the chain to come off the small rear sprocket to the left. This is nonsensical.
In a concurrent post on Bicycle Mechanics, the OP claimed the chain came off the front chainring to the left. This means the chain passed through the gap between the chain guide and the chainwheel disc - a gap that is smaller than the chain is wide. THEN after magically getting past this small gap, the chain climbs up over the chainwheel disc to come off. This is also nonsensical.I again ask the OP to rejoin the thread and explain.
In this thread, the OP claimed the rear wheel was respaced a few millimeters to the left which caused the chain to come off the small rear sprocket to the left. This is nonsensical.
In a concurrent post on Bicycle Mechanics, the OP claimed the chain came off the front chainring to the left. This means the chain passed through the gap between the chain guide and the chainwheel disc - a gap that is smaller than the chain is wide. THEN after magically getting past this small gap, the chain climbs up over the chainwheel disc to come off. This is also nonsensical.I again ask the OP to rejoin the thread and explain.