I've had my DK for a little over a month now and I've noticed that the chain had seemed to loosen up or stretch a bit. The bike no longer had that solid "dialed" sound when I drop it on it's tires. The chain now wobbles annoyingly. I checked the dropouts and there's no indication that the wheel has moved at all - still tight and centered. I don't want to have to back the wheel off just to tighten the chain. I don't mind it being a little loose. In fact, when it was much tighter, it occasionally made a strange clicking noise when I pedaled - like it was skipping a bearing. I could actually feel the cranks pop forward. It hasn't done that since it loosened up. If I had a choice, I'd let it wobble.

Now, the chain(KMC z-410H) came with the bike when I bought it I'm going to be replacing the entire chainset soon for smaller gearing. The new chain will either be a KMC K710SL or Shadow Conspiracy Interlock2.

So, is chain stretch normal? Or does it happen mainly with less expensive chains? Will I need to add a chain tensioner with the new drivetrain? From the many bike checks I've read, they don't seem that popular.

Yes, chain stretch is normal. Some chains stretch less than others though. Ex: The Shadow Chain stretches ALOT.
You will still need to re-adjust your wheel in the dropouts. A chain tensioner does the same thing as you moving the rear wheel back.
-Bill

Ex: The Shadow Chain stretches ALOT.


Wow! For almost $30, you would think not huh? I guess you just pay for the prettiness!

A chain tensioner does the same thing as you moving the rear wheel back.


Excuse my confusion...If you are moving the rear wheel back, aren't you already tightening the chain? What is the tensioner doing if you're already having to move the wheel? Maybe I was thinking that the tensioner allows you to tighten the chain without moving the wheel.

The Shadow chain is more than pretty. But it does seem to be hit or miss. Some people have no luck w/ them, others(like me) have had no problems with it. Due to it's half-link design, it stretches more as the links try to straighten out. But once it stretches, it fine. At least that's been my expeirience with it.

You are not confused at all, all the chain tensioner does is simply pull the back wheel back to tighten the chain. More often than not, you get the same results w/ out it. I only use one when I'm running a Demolition Dumbchuck peg. The plastic shell on that peg has a tendancy to make the wheel slip.

There are tensioners that do what you describe, but they are made for SS MTBs & won't work on a BMX frame.
Plus you'd bash the heck out of it on the first grind.
-Bill

just tighten the **** out of them no need for chain tensioners its just a waste of money. ive heard before the dudes from terribleone put grease on there axels threads and then but the bolt on tighten them up. never tried it and i dont really see a reason to try it but just a suggestion.

All chains strech.
Tensenors keep the wheel from moving,not the chain from streching.
I've ran both chains___Shadow < KMC 710 SL

I think chain tensioners make it easier to tighten/loosen your chain. And I have the 710 SL and it is pretty good. I've never used any other chains though besides the stock ones and the crappy ones from X-Mart.

Once they're set, tensioners will make it easier to set the tension the same later after you've removed the back wheel and put it back on again (to fix a flat or whatever). They're pretty fiddly the first time though IMO.

It seems that the general consensus is that a tensioner is not really necessary - especially since simply re-adjusting the rear wheel achieves the same results. I'll probably forego the tensioner for now. Thanks for the input people!

I'd say it depends a lot on how often you're having to readjust/remove the wheel. I personally love having chain tensioners because they help me get the wheel perfectly straight, they make it easier to put the wheel on and keep the chain tight, and you know that even if something comes loose you have the backup. I even went the crappy hardware store method, drywall hangers and eye bolts, on my pawnshop bike.

Anything that helps me put the wheels on perfectly would be worth the $$. Straight wheel>tight chain.

Anything that helps me put the wheels on perfectly would be worth the $$. Straight wheel>tight chain.

In that case, get the chain tensioner (CT). For racing, I am very particular on the tension of the chain and that the wheel is absolutely straight. The CT makes this easy to accomplish quickly and keeps it that way. Chain too tight and it slows you down, too loose and you get what you describe in your first entry.

I run two tensioners, because I'm lazy...

I tried just using one, but two makes it a **** load easier.