New Chain install

[thing2_and_thing1]

I have run out of adjustment on my chain. I assume that the chain has been stretched enough so I bought a new on instead of cutting a few links out of the old one. I bought a renthal 420 x 130. I will need to cut a few links out so what is the best way to decide how much. Do you just push the rear tire all the way forward and cut the chain leaving some slack so not to cut too much or what? And is the old chain still of any use. It is not in bad shape but I do not know how much stretch is in a chain before it just gives up.

I did a search and could not find an answer. I have a shop manual on the way but have yet to receive it. :bang:

 

[jaction125]

First, buy new sprockets as well. If you replace the chain without the sprockets you will waste the chain.

Some sites will give you an idea on how long the chain should be. Post up what spockets you're running and what bike they're going on and we'll see where you need to be.

 

[FruDaddy]

Do you just push the rear tire all the way forward and cut the chain leaving some slack so not to cut too much or what?

This is basically what I do. Remember, you can cut more off, but adding on without a second master link sux, err on the side of leaving it too long. And yes, you should replace both sprockets as well. If you aren't happy with the current gearing, this is a good time for that as well.

 

[thing2_and_thing1]

Okay, per your suggestions I now have both new sprokets. That just made the job bigger. Front sprocket: pull sprocket cover off engine, remove retaining ring, remove/install sprocket. Rear sprocket: remove rear break caliper, remove axle, pull rear tire and change sprocket.

Am I leaving anything out? About a 2 hour job ???????

 

[RM_guy]

2 hours sounds right. Pick up a small chain breaker too. They are well worth it. Instead of counting links I usually put the chain on both sprockets to find out the right length and then break the chain right on the bike. There's nothing worse than miscounting and ending up with a short chain :ohmy:

 

[nickyd]

2004 KX 100.....per my distributor's book, stock gearing is 51 x 13, chain was 420 x 124.

 

[elcamino12sec]

I recomend soaking the chain in motor oil over night before you install it. According to nickyd you need to cut out 6 links and install it. Its always a good idea to inspect the brake pads and lube the rear bearings while you have it apart. I use blue loctite on the sproket bolts, I have always had problems with them lostening up during a ride. Taking a few extra minutes now can save you few hours later.

 

[thing2_and_thing1]

Well get ready to rebuke me. I have the new renthal chain, and a set of OEM sprockets but I just could not bring myself to put them on tonight. As of late I have done quit a bit of riding in the sand because that is where the best jumps are close to my house. I wanted to get a few more rides in the sand and get it out of my system for a while before I put on those beautiful new parts that the sand is going to eat. I cut a link out of the old chain and am going to play a few more weekends in the sand. It also gave me practice cutting a chain.

Side Bar... the old chain looks as if it is being sharpened on the edges. Is this from the chain guide on the bottom of the swingarm being worn out or just full of sand while I ride. I clean the bike after each ride including the chain guide.

 

[elcamino12sec]

take apart your chain guide, it should only take about 5 minutes. Inspect the plastic blocks that wear when it slides on it, there is an upper and lower, same with the swing arm by the front sprocket, its called the slider. if these are worn you should replace those too. Or it could be that your chain is too loose. while your at it, inspect the upper and lower rollers too, make sure they roll free and have plenty of life left in them. if it were me, I would tear down the whole swing arm, shock and linkage, inspect, clean, lube and re-assemble everything. after that you are confident the back half of the bike is all good to go for up comming summer. I hate to have to fix things in the middle of riding season. Its the same reason why I work on my boat during the winter, its sucks to wait on a Suzuki outboard part to come from japan in the middle of Grouper season in Florida. happy trails!

 

[FruDaddy]

I never remove the brake caliper if I don't have to, I just slide the wheel out of it. And do NOT cut the chain until you know for sure that the length will be right.

 

[Agitator]

Couldn't you just count the same number of links on the new chain as the old one has? (provided the old chain has not had links removed to account for stretch).

If you're supposed to replace the sprockets and chain all at the same time EVERY time, then why is there so much talk about "saving your sprockets from wear due to chain stretch?" If you have to replace the sprockets every time, why not get all the life out of the chain that you can... Use it until it has stretched considerably, but still is not likely to break..?

correct me if I'm wrong, but-
Jaybird said something along the lines of:

(not a direct quote)
"you may have to replace your sprockets upon replacement of the chain, if they are worn, but if they are in good condition, sprocket replacement is not necessary"

I could easily be wrong...

curiosity k*lled the cat~

 

[nickyd]

jaybird is right - there is a point at which the chain has not stretched enought to "hook" the sprockets...do most of us monitor it close enought to run a new chain and save the sprockets...doubtful...I have a fancy little tool for the bicycles that I use - basically lets you know when the chain is close to done....12 links = 12 inches...if 12 links =12 1/8 inches, the chain is done....there is a similar principle for dirtbikes but hell most riders need to spend more time with their air filter and oil than they do with there chain

 

[Agitator]

So if the sprockets look really good, is it safe to assume that they do not have to be replaced along with the chain?

I need to make a gauge like that for my chain..It would definitely save me a lot of time.

Thank's for the reply

 

[nickyd]

A ruler works just as well - count 12 links. pin to pin - if its 12" great - if its worn to 12 1/8", call it a day...this is the measurement for mountain/road bicycles - not sure how this translates over to MCs.

 

[FruDaddy]

Measure a new chain and write it down for reference. You will get a more accurate measurement if you put the bike on a stand and hang a 10lb weight from the bottom section. This will pull the top of the chain tight. Also, measure pin center to pin center.

 

[Agitator]

Thank's for all the tips!
nickyd: I meant I should make somethin' of a gauge for my dirtbike chain... chain wear on my mountain bike has never been a huge issue (for me, the lazy rider at least).

I'll be sure to measure from pin center-to pin center~

 

[FistFullofDirt]

I dont know whether my sprockets need changing or not. But I wanted to know what you guys think about getting a new chain and not changing the sprockets to ride slow and learn the bike a little bit. Then in about a month or so change everything.

 

[FruDaddy]

If you need a new chain, then you need new sprockets, if you are just puttng around, then the worn chain will probably be OK. If you put a new chain on worn sprockets, then you will accelerate the wear of the chain, so you will just have to repalce it again in a month (when you do the sprockets). Of course, when you do replace everything, you can put the mildly worn chain in a box in case you ever need a spare. I wouldn't do it, but you can if you want.

 

[FistFullofDirt]

Actually sounds like a good idea. Bought chain in town. Ordered chain and sprocket set online. Will ride on new chain till set comes in.