Chain tension increases as wheel spins.

[vim420]

Hello I've got a 1980 xs400 special 2. I was noticing a grinding noise and determined it was coming from the chain. Upon inspection I noticed that as the tire rotated everything would be normal until it would hit a spot where the chain tightens up. For now I have the tension set at the tightest spot but it's fairly loose everywhere else. Do I need a new chain? Sprockets? Maybe the chains all gummed up or something and could use a good clean/oil. Any input appreciated! Thanks!!!!

 

[bcware]

New chain.

Most people recommend changing the sprockets and chain at the same time to maximize the life of both; they are fairly cheap for these bikes. Because chains are so cheap for these bikes you can, in my opinion, easily justify just replacing the chain if the sprockets look ok. I think I got my current chain for like $20 shipped. If you were talking a high end x-ring chain for a superbike worth $200+ I would definitely make sure the sprockets were new. Anyway, it's up to you.

You did the right thing though; set the chain tension at the tightest point on the chain.

Also, just fyi: chains tighten up as you A: sit on the bike and compress the suspension and B: as you accelerate.

 

[vim420]

sweet thanks!! The sprockets looks fairly good, bike has less then 10k miles. I have never bought a motorcycle chain before, any help directing to the proper size and length would be greatly appreciated! As well as where to buy one, im in canada, bike is from the states.
Thanks for the quick reply!!

 

[kshansen]

Depending on how much you are planing on riding this bike you could just go to a farm supply house and get a standard roll of roller chain. I could be wrong but seems like the XS400 runs a #50 chain. If you can ride the bike to the store you could just compare the different sizes. The farm stores in the US usually sell this chain in 10 foot lengths. You then just cut it to the size you need.

Do not remove your chain yet! Paint one link on your chain then count how many links your chain. Do this at least three times to be sure you get the same count each time!. Don't count the master link. Then do the same thing on the new chain. Just grind off the rivets of the next link in the chain and you should be able to use a small punch to tap the link apart.

To install the new chain remove the master link from the old chain and use it to connect the new and old chains together. Now you can pull the old chain out while feeding the new one in. Of course you will have to back off the adjusters on the rear axle to get the two ends of the new chain to hook up with the master link. It's always a good idea when installing the clip on the master to have the open end pointing away from the direction the chain travels. When on the top it would be open towards the rear.

Now if you are planing on riding your XS400 to Nova Scotia and back you may want to go for the bike specific oring chains. Your money your choice. But I would bet that the original chain the factory used back in the 1970's was no better than what you will get in the farm store.

 

[bcware]

I'm told #50 is the same as 530 chain in terms of size, but a 530 heavy duty chain is significantly stronger.

I used a standard heavy duty non-o-ring chain from Bikemaster I believe.

O-ring chains will last longer, but I don't do enough miles for it to really matter and the non-o-ring chains are dirt cheap. I don't care if they don't last as long.

People seem to say the link length is 98 to 102 depending on the sprocket setup. You can buy the longer length (102) and grind off the excess.

If you don't have the ability to grind count your existing chain links very carefully as mentioned above. In fact, I would just count anyway to be absolutely sure!

I run a clip-type master link. I am ok with these on small bikes, but I would avoid them on more powerful bikes. Installation of these master links is directional!

 

[16VGTIDave]

There is a big difference between an industrial spec chain (#50) and a motorcycle chain (530). O-ring chains last much longer and are easier to maintain. Clip master links are much weaker than a riveted master.

Don't cheap out.

 

[kshansen]

There is a big difference between an industrial spec chain (#50) and a motorcycle chain (530). O-ring chains last much longer and are easier to maintain. Clip master links are much weaker than a riveted master.

Don't cheap out.

That is why I prefaced my comment with "Depends on how much riding you will do" also the kind of riding. I ran the cheap tractor supply chain on the XS650 I rode to work year round. Two major reasons, first one way it was only about one mile. Second as I knew I was going to be running in the salt and slush or winter I knew even a good o'ring chain would never last for long. In over 12 years I think other than the chain the bike came with I only replaced it twice with the cheap stuff.

As for the clip vs. riveted master, I ran a clip type chain on my 1200 Sportster for over 100,000 miles (not the same chain!) and never had a failure of a master link.

I know of at least one guy with an XS650 that always runs the cheap chain and what he does is keeps a spare cleaned and oiled. A couple times a year he will pop the master apart on the chain on the bike, hook the spare to it, pull on out and the other in reinstall the master, adjust chain as needed and then clean and soak the removed one in oil. Repeat as needed! Claims he gets a few years out of a pair of chains.

Now if you were going to be doing cross country rides this probably would not be the way to go, but as Yamaha used to say "Different Stroke for Different Folks" Makes me wish I still had that RD400 I rode many years ago.

 

[bcware]

I've never seen any definitive proof that a clip type link is any less safe. It's all anecdotal evidence. Just stories people tell and nothing more. There is no way to know if these people with their horror stories simply installed them incorrectly or did something else to damage them somehow. People also put chains on bikes they are not rated for in terms of tensile strength.

I've had plenty of chains on the used bikes I purchased over the years come with riveted chains that were botched; they were overtightened and this posed more of a risk of breaking than a clip type ever would have.

That said, it's still just an opinion. Manufacturers of the clip types stand by their integrity, however, and that matters to me slightly more than some random person's story on the internet.

 

[16VGTIDave]

I'm gong to stick with my previous statements. When one considers the numerous factors involved, such as chain speed, shock loading, harmonics, applied torque, lubricant retention, manufacturing tolerances, weight, sprocket wear, maintenance time... Just to name a few factors that come to mind, is it worth "saving" $30 on a cheap chain?

I have never lost a master link, but have met many who have. Some with catastrophic results, and one with permanent personal injury to his leg when the chain tore through his boot, lower calf and tendons...

It is interesting to note that higher strength chains do NOT offer clip master links, regardless of the application. Heck, even my bicycle chain is riveted. Why would one even consider a clip master if it isn't good enough for a bicycle???

 

[XSLeo]

Even with a new chain and sprockets you might notice the chain tension changing as the wheel turns. No sprockets are perfect. The center hole may not be exactly centered, the teeth may not be all cut the same, the sprocket can be out of round.
The chain, the links are not all the same length. pins not all the same diameter, same with rollers.
The manufacturers try their best. But even new parts can be off.
When you install the new parts spin the wheel and see. The difference may not be much but it's there. Always adjust the chain at the tight spots.
One way to see this is ride along by another bike and watch the chain. You can see this effect more so as the engine is pulling on the chain.
Leo

 

[bcware]

All non-o-ring chains are fairly cheap; one can still get a decent name brand with a clip link for short money without sacrificing quality.

It also simply isn't true that high performance chains don't use clip links; not all of them come with them but many have them available from the manufacturer. If you google this you'll find lots of results from EK, DID, etc.

I'm sorry to hear that someone you know got hurt due to a chain, but I have no idea why that accident happened. There are so many variables involved and there is no way to know where the fault lies.

I still stand by what I said previously; I have never seen more than purely anecdotal evidence in regard to the safety of one type of link versus another. For me this means I cannot make a conclusion one way or the other.

I'm not saying clip links are better, just that there is no evidence, to my knowledge, that they are any worse in this application.

I'm sure you can dig something up somewhere about super high power machines needing them, but that's a little too off target for me. We're talking about xs400s here.

 

[ScottLuke]

non- Oring chains are everywhere, but require more maintenance. And can last longer. #50 chain is pretty strong, not sure about the tensile strength but I bet it's not going to break under the load of a 400. I run a river link on my 450, but not on my other bikes, clip style link is perfectly fine as long as it's facing the correct way. Nearly all pro racers run non-Oring chains because they cause less drag. When I raced I used a non-Oring DID chain and afterwards put it into a bucket of kerosene to clean it, then into a separate bucket of 40w. Which lasted me a full race season of pretty hard enduro ISDE