dolt

Hi-
I'm a novice rider and you guys helped me out a few months ago with some great advice, so I'm back with two more questions:

1. I bought my Dahon Speed D7 Street brand-new less than two years and since I'm a casual rider, I've only put about 275 miles on it. A month ago, I hit a pothole badly and immediately the chain started slipping on my 7th gear; now 7th is basically unusable, though all the other gears are fine. The rear derailleur seems to get stuck if you 'dig in' while pedaling and gets pulled into a near-horizontal position; I think that's when the chain slips, but it's hard to tell because I'm riding when this happens and it's hard to look down there and not crash.
I took it to a shop the other day and the guy diagnosed it, saying I need a new chain and gear set because I'd worn down my 7th gear. Like I said, I'm a complete novice so maybe I have no idea what I'm talking about, but that sure seems like a short lifespan for a gear set. Since the derailleur gets stuck, is that the problem, or is that a symptom of a worn-down gear?
Either way, I'll have to get it fixed, and yeah, I'm sure replacing everything whole-hog will do the trick, but I at least want to learn something and explore all options before I throw $150 at a problem on a $400 bike.

2. I'm debating on replacing the stock Kenda 20" x 1.75" tires it came with. Any suggestions as to what might be appropriate? I've seen Big Apples mentioned a lot here on the forum, but they don't seem to come in sizes smaller than 20" x 2.00" and I'm not clear what the benefit of those specific tires are anyway other than they're what everyone seems to use.

Any insights would be really appreciated. Thanks!

termv

Sorry for your problems,

Maybe you can bend the rear derailleur back in shape if not upgrade to something like a Acera M360, price is around $22

​​​​​​However, is your hanger still fine?

Good thing your bike is basically made from steel.

Tire wise you could indeed go the Schwalbe way, OR Maxxis.

Maxxis has some good choices like Hookworm in 20x1.95, or the Ringworm also in 20x1.95. However. I would definitely not pump them up to 110 PSI for obvious rim reasons.

The Wall which I no longer see available was 20x2.10 (70 or 75 PSI) was an excellent choice too.

Currently I am waiting for a set of Maxxis Max Daddy 20X2.0 (40 PSI). Hopefully I don't have to to take the Fenders off. If I can only have the Daddy on the rear but keeping the Fenders on than I am still happy.

In the back, MAXIMUM is 2.10! The chain will otherwise rub against the tire!!!

At that size you MUST change the Fenders in order to accommodate them.

Thorusa is a good source for the fenders.

Hope this helps.

​

3speedslow

The schwalbe Marathon racer is an excellent tire and won’t cause fit problems

bikebikebike

Derailleurs get buggered up easily on MTB and 20"bikes, but did the chain get bent, too?
pics and specifics would be helpful, even if just in the "post game"followup
It would be good to have a follow up. Get the LBS to show you what they found
A derailleur straightener is a great tool , even just for checking alignment, an simple ebay ones are cheap.
and foldies are vulnerable to getting misaligned there.

jfouellette

I recently bought a used (2007) Dahon Speed. The original tires were dry and one ruptured as I was testing it with an air pump. My LBS didn t have much choice due to supply issues. I went with Schwalbe Marathon Plus (e bike ready!) . Expensive but they seem very good. Size 20 x 1.75. The front fender had to be adjusted because of rubbing.