Folding Bikes - Downtube crank wheel broke

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View Full Version : Downtube crank wheel broke


MicheleC
07-16-08, 09:51 AM
Hi Everyone,

The crank wheel on my Downtube broke in 2 places and is cracked in two other places (the plastic where the screws goes through cracked in all these places). Can this be replaced? How easy is this to do?

What I have is, I believe, a 2005 Downtube VIII. I think I bought it in 2005.

Thanks,
Michele


Dynocoaster
07-16-08, 09:55 AM
I would get the new forged crank from Downtube, it is on sale. I would send Yan an email and make sure it will work for you.

MicheleC
07-16-08, 10:01 AM
I would get the new forged crank from Downtube, it is on sale. I would send Yan an email and make sure it will work for you.

I just sent off an email to Dr. Yan to ask about the crank on sale and will look for his reply to see whether it will work. Thanks!

Michele


Sammyboy
07-16-08, 10:12 AM
If it's just the chainwheel, then you can get a replacement cheaply (or any bike shop can replace it). The new cranks will certainly work, and again, it's a quick and easy job to switch them,.

BruceMetras
07-16-08, 10:21 AM
I'd guess she's talking about the plastic chain-guard/pants-guard... not the chainring or crank ..

MicheleC
07-16-08, 10:33 AM
So, I can just pull the rest of the plastic piece off and not worry about it? The chain will stay on without it?

Well, now I feel pretty stupid. . .

Michele

BruceMetras
07-16-08, 10:34 AM
If it's just the chainwheel, then you can get a replacement cheaply (or any bike shop can replace it). The new cranks will certainly work, and again, it's a quick and easy job to switch them,.

Not on an 05 as i recall, the chainrings were not individually replaceable ..

SesameCrunch
07-16-08, 10:36 AM
So, I can just pull the rest of the plastic piece off and not worry about it? The chain will stay on without it?

Well, now I feel pretty stupid. . .

Michele

The plastic ring that's bolted outside of the geared ring is just there to protect your pants from getting grease on them. It's not critical in any way. If that's what's cracked, you don't have to worry about anything. :thumb:

BruceMetras
07-16-08, 10:43 AM
So, I can just pull the rest of the plastic piece off and not worry about it? The chain will stay on without it?

Well, now I feel pretty stupid. . .

Michele

Don't feel that way, all questions are welcomed here.. what seems stupid to you might be an epiphany for someone else.. If the chain was staying on ok for you before, it will continue to stay on.. if it was jumping off and getting caught between the chainring and the plastic guard and leading to the demise of the guard, then you will have chain drops.... you might be able to get a new inner/outer plastic set from Yan..

Sammyboy
07-16-08, 02:11 PM
I quite agree. We're here to help, and if you can't ask questions, then how will you learn anything? This saved you spending a chunk of cash on new cranks, and a fair bit of work putting them on. It's good you asked.

Dynocoaster
07-16-08, 02:19 PM
it is great that someone picked up on the fact it was the plastic part.

MicheleC
07-20-08, 09:23 AM
Thanks, everyone! I did pull the rest of the broken plastic part off and have been riding with no worries. I"m glad I learned something, too!

werewolf
07-20-08, 09:55 AM
So, I can just pull the rest of the plastic piece off and not worry about it? The chain will stay on without it?

Well, now I feel pretty stupid. . .

Michele


The nomenclature of bike parts is confusing. I've been messing with bikes for my whole life and I still can't remember what stuff is called.

snafu21
07-20-08, 11:07 AM
I'm still trying to figure out how to change the blinker fluid.

BikeBloke
07-20-08, 03:59 PM
I'm still trying to figure out how to change the blinker fluid.

you'd be better off just buying a new blinker to be honest. i got one for £3.75 in poundland. or you could replace the whole clampshaft tensioner bracket with a new self-lubricating spline module and be done with it.

Sammyboy
07-21-08, 02:49 AM
replace the whole clampshaft tensioner bracket with a new self-lubricating spline module and be done with it.

I keep hearing this, but it's false economy. The clampshaft tensioner is purpose designed, and the spline modules that everyone is using are given to sudden catastrophic failures at speed. You can buy blinker fluid from the manufacturer. It's expensive at £150 a bottle, but it's what's designed for the bike - if you want to take care of it, take notice of the manufacturer's instructions!