Changing Chain and Sprockets

[madmatt]

What is the best and fastest way to change out the chain and srockets on my 99 YZ125? I haven't gotten to that part after putting new bearings in the front wheel and rebuilding the top end and clutch. Also, does anyone have any recommendations for a chain and sprockets? I have Renthal front and rear sprockets (stock Gearing) and a DID chain.

 

[madmatt]

Come on guys! 38 views on this thread, and NO replies? I am starting to think that noone likes me here!

Matt

 

[slo' mo]

Originally posted by madmatt
What is the best and fastest way to change out the chain and srockets on my 99 YZ125? I haven't gotten to that part after putting new bearings in the front wheel and rebuilding the top end and clutch. Also, does anyone have any recommendations for a chain and sprockets? I have Renthal front and rear sprockets (stock Gearing) and a DID chain.

I guess we all figure if you have already rebuilt the top end and clutch, the sprockets would be a minor thing. Front sprocket is easy. Back one you might want to remove the wheel first. ;) Be sure and use a new chain if your old one has any wear. It's better if you change them as a set.
I always like to mark the axle slider positions with a sharpie to make sure I get the wheel back on straight. Use a thread locker on the sprocket bolts (blue)

 

[MikeT]

here http://dirtrider.net/forums3/showthread.php?postid=437928#post437928

 

[bclapham]

btosports.com have some good deals on renthal sprocket combos for about $90-120 depending on the chain. do the whole lot at once and think about how your bike is geared and how you might want to change it!

 

[MikeT]

matt, get a TITAX machined AL rear sprocket from Rocky Mountain $29, and their Primary Drive front sprocket for $6.99. These sprockets are made of the same stuff the Renthals are for a fraction of the cost. Also you can get an RK X-ring chain from Rocky Mountain for $51.

Can't beat it!

 

[madmatt]

Thanks guys, I really appreciate all of the help! How can I judge how much chain wear is too much??

Matt

 

[madmatt]

Hey MIKET, does Rocky Mountain have a website? I couldn't find one for it, and I thought maybe you would have the addy for me!

 

[MikeT]

Your manual should have a wear limit that you can go by.

 

[bclapham]

www.rockymountainmc.com

 

[MikeT]

http://www.rockymountainmc.com

1-800-336-5437
Excellent customer service and very nice people

 

[madmatt]

What do you do if you don't have a manual? Do you guys know where you can get one or all of the general specs for my bike? Surely there is an internet site that would have these posted! Thanks again guys for all of the great response!

 

[MikeT]

I'll have to look

 

[MikeT]

Measure 10 link pins center-to-center(taught). Once that measurment reaches 6 inches...replace the chain and sprockets.

 

[geremacheks]

When you order a chain and sprocket set for your particular bike, do you have to add or cut out links in the chain? It would be nice if a new chain with a master link would just fit on your bike without any chain links added or subtracted. Does this usually happen?

And do most of these chains have master links, or do you need a chain breaking device? Thanks. As you can tell I want the simple way.

 

[jboomer]

At rockymountain, you can order how many links you want on the chain. I counted how many links were on my old one (I added one more tooth to the rear sprocket -- so I added two links) and ordered that length of chain. It's still about 1 link too long, but I'll wait until it stretches out before I shorten it. But, it's always better to have too many links than not enough!

If I were you, I would invest in their little $20 master link "press" tool (it's called a "Motion Pro Press Tool"). I always used vice grips to squeeze the heck out of my master link (o-ring chain) in order to get the little clip on. This little press tool made it really easy! --Money well spent.

 

[little jeff]

Get a Sidewinder sprocket and chain combo. Probably be the last chain and sprockets you'll buy for a long time in my opinion.
Little Jeff

 

[2000SE]

are DID O ring chains even any good?

 

[MikeT]

Originally posted by little jeff
Get a Sidewinder sprocket and chain combo. Probably be the last chain and sprockets you'll buy for a long time in my opinion.
Little Jeff

Not in my case. I bought the Sidewinder stuff and it did not perform well on my bike. The sprockets are fine but I am now running an RK X-ring chain.

If I had it all to do over again, I'd buy the RK X-ring and the Titax sprockets.

 

[MikeT]

Originally posted by 2000SE
are DID O ring chains even any good?

I haven't run one yet, but they are about $20 more than the RK X-Ring.

 

[motometal]

that tool to press on the connector link is nice, but in my opinion not needed. when you use a vice grips, take a really small box end wrench, and put this over the grooved end of the connector link on top of the plate. squeeze a bit on one pin at a time, and it will go right on. Stop when the full groove is exposed, you don't want to squeeze the rubber rings any more than needed.

 

[Jaybird]

Originally posted by madmatt
Thanks guys, I really appreciate all of the help! How can I judge how much chain wear is too much??

Matt

Once a chain reaches 3% growth it can damage the sprocket teeth and should be changed out. Remember when measuring for wear, the first pin is 0 which means a ten reel measurement involves 11 pins.

 

[madmatt]

Thanks Jaybird! That is some really good information that I really needed! I am going to go home and get a measuring tape ASAP!!

THANKS AGAIN!

Madmatt

 

[Jaybird]

Glad to help, Matt.
Be sure you have your chain taught when you measure so all the slack is out. Put the bike on a stand in first gear and tighten the chain with the rear wheel. Measure on the top side of chain and you can do this by yourself, it is a little cumbersome though trying to measure while holding tension. You also can get a buddy to help.

 

[23jayhawk]

Or you can hang a 5 lb weight on the lower run to pull out the slack.