Motorcycle Racing Forum

Motorcycle Racing => Wrenching => Topic started by: H-man on March 02, 2005, 09:03:48 AM

Title: When to change...?
Post by: H-man on March 02, 2005, 09:03:48 AM
Now that I've got you're attention ;D

I did a search and came up blank.  I'm looking to learn when the bike's chain (final drive chain) should be changed.

I've read it s/b changed when it gets "stretched out", but:

How do you determine that it's been stretched?  Is it that when you check the chain you notice it's loose?

What is the point when instead of adjusting the chain tensioner, you replace the chain?

Oh yeah, is the adage of changing the sprokets whenever the chain is swapped out really necessary or is that a marketing gimmick?

TIA

  H-man
Title: Re: When to change...?
Post by: spyderchick on March 02, 2005, 09:34:38 AM
Well, the adjustments and lube should be done regularly. (of course) When you do this, the bike is up on the rear stand. As you rotate the rear tire manually, you will noticed "tight" spots and "loose" spot,  these are caused by chain wear. If you have excessiveness (this can be subjective) with this type of condition, you should change the chain. Say you have one tight spot, you can adjust that out, but more than that, I think it's advisable to think about replacement. Also, look for "kinks" in the chain. If you start to see those, it's probably time to bin the chain as well.

I'm sure others have their opinion on the subject.

Also, it's advisable to go more on the loose side with the chain adjustment, because a tight chain can actually limit your suspension, and this can result in breakage under stress.

We;ve used various aged chains with various aged sprockets, but that's just the nature of budget racing.
Title: Re: When to change...?
Post by: Steviebee on March 02, 2005, 11:07:28 AM
I've also heard.

put the rear on a stand and rotate to the tight spot.  Then pull on the rear of the chain (in the middle of the sproket grab the chain and pull straight back) and see how much it pulls off the sproket,  .25 inches and u need a new chain.


I heard some guys say they replace after 3 races ??  I ran mine for 3 years proally 20 weekends of racing or trackdays.  

The chain still feels, looks, great.  But im getting a new one and gonna use this one as a backup.
Title: Re: When to change...?
Post by: Steviebee on March 02, 2005, 11:10:15 AM
QuoteOh yeah, is the adage of changing the sprokets whenever the chain is swapped out really necessary or is that a marketing gimmick?

  

applies to you if you want to keep your chain for 20000 miles.

I change sprokets and keep the same chain.  But if a sproket shows wear i toss the sproket.

Iv'e had a sproket get shewed up but not mess up the chain.   Gotta love ALuminum sprokets.  Stock ones are steel and much harder.
Title: Re: When to change...?
Post by: H-man on March 02, 2005, 12:40:32 PM
Thanks for the input guys.  Uh... guy & gal ;)

If anyone else has different methods used to evaluate the chain, pls chime in.
Title: Re: When to change...?
Post by: tigerblade on March 02, 2005, 12:59:16 PM
I was at Deal's Gap a few years ago when a guy with a ZX11 decided to do a dyno run at the Crossroads of Time (I forget what they're calling it now) shop.  As he pulls onto the dyno, we got to noticing his chain.  It was stretched so bad you could see daylight through the links.  If you can see daylight, you've waited too long.   :o

I've always wondered what might have happened if we didn't stop them from going ahead with the run... :-X
Title: Re: When to change...?
Post by: tshort on March 10, 2005, 06:16:42 PM
My Suzuki manual says that the limit for 20 pitches of a 525 chain is 319.4mm (use a dial caliper).  Regina uses a different number, but same idea: http://www.reginachain.it/eng/use_and_maintenance/how_to04.shtml#02


I wouldn't guess.  I wouldn't replace every three weekends.  On the other hand, if you're doing a bunch of races every season, why not drop $100 a year on a nice new chain, take the old one off and toss it into your spares box - never know when you might need it.
Title: Re: When to change...?
Post by: H-man on March 12, 2005, 05:26:54 PM
Excellent reference site Tom.  Thanks.

That makes good sense about just replacing the chain as (relatively) cheap insurance and using the existing one (provided it passes the measurement test) as a spare.

Sometimes the simple or obvious eludes me.
Title: Re: When to change...?
Post by: ekraft84 on March 21, 2005, 04:28:49 AM
H, I replace the chain every season.  During the season, I'll take the chain off after say, every other race weekend and soak it in WD40.  Then clean it up and it's ready to go.

I'll replace my main sprockets as well every season.  The ones I don't use as much, I watch for wear (by looking at the teeth) and replace them as needed.

Haven't had a problem yet (knock on wood).

Title: Re: When to change...?
Post by: H-man on March 21, 2005, 09:01:27 AM
Thanks Eddie :D

I'll keep that bit advice in mind.  Although your steeds are put through more than mine (both in terms of number of races per weekend and how hard you ride vs. me 8)), that's a good starting point that I can always alter.

Later my friend.