chain rub@ chain guard--2006 dahon p8
 

Hi all,

I post my problem on dahon forum but I didn't get any clear answeres or solutions. I'm posting it here hoping someone can point me to the right direction.

I just got my dahon speed p8 (via internet) couple days ago and what I discovered was a loud rubbing sound from the crank area when I shift into 6,7 or 8th gear. upon closer inspection, the chain shifts to outside of the bike when using these gears and hence causing the chain grind with the chain guard. I was going to tour on this bike in Aug. (calgary to jasper) but now I'm having second thoughts. may be I should use a mtn bike instead.

here are some suggestions that I got from dahon forum:
1. the bike is still in the break-in period and may be the problem will go away if the chain has been streched.
2. change to a longer BB
3. add washers between chainring and chain guard
4. change to internal gear hub

if anyone on this forum has a suggestion or remedies with out breaking the wallet, please let me know


thank you very much

bend the chainguard.

Maladjusted derailleur? (Check the high/low set screws)
Crooked derailleur? (Not even with chainring because it was bent during shipping)
Crooked rear dropouts?
Remove chainring guard completely?
Bent chainring guard?
Crooked rear wheel? (Reinstall in dropouts)
Cassette installed incorrectly?

The chainguard on the P8 is a cheap, flimsy piece of aluminum. Eventually it gets bent one way or the other from normal use. When I first got my P8 and got sick of grinding I kept unbolting the chainring and flipping the chainguard to give a little more clearance, but it would eventually bend/wander back to the annoying position. It gives a temporary feeling of relief, if nothing else.

One thing that the Dahon Tech suggested about this problem is switching to a 9-speed chain, which is narrower, and thus grinds less. This could be something to try that costs less than $20.

Many people simply remove the chain guard. I had problems with the chain jumping so I ordered an
additional chain guard (one on each side). When I installed the crank backwards and the chain rubbed
the chain guard. I flipped it and the problem went away (and i don't lose the chain anymore)
So try flipping the crank. If it doesn't work, ditch the guard.

cheers

CE

hi CrimsonEclipse, Your solution sounds good but I'm a little puzzle about fliping the crank. what do you mean by fliping it?

thank you

oh sorry.

removing it and then flip it like a coin 180 degrees. If you look at the crank, it has an offset, meaning
that the teeth of the crank is a few milimeters off center of the mounting screws so, if it is mounted
backwards, it would be to closer to the chain guard by a few MM and possibly rub.

I'll see if I can take a picture.

CE

hi CE,

I flip the chainring lastnight and the rubbing is gone when in the high gear. thanks for your info :)

pxboii