ybr chain question

[ozymaster]

Recently bought a ybr 125 and the fella said it was ready for a new chain, now me being a newbi how do i tell? Chan looks ok to me but the unless it was snapped i doubt id know any difrence.

Also what chains best to get and were from? Is it best to get oem from dealer? Or are there better aftermarkets?

Also do you change sprocket and chain together?

Lots of questions but i realy am a new

:-)

[nayruf]

I reckon chain maintenance is one of the things that put people off having a bike, that and the possibility of a visit to A&E,

The question has been asked so many times that you would probably get plenty of information from the site by carrying out a forum search for ‘Chain replacement’ or just ‘Chain’

There are a few ways of checking that a chain is worn; from checking the length of it stretched out over a given number of links compared to the same length measurement when the links are compressed and the difference of these measurements can be used as a ratio to calculate how badly the chain is worn. The physical condition of the chain needs to be looked at for damage/wear to rollers, chaffing of the side plates corrosion, stiff links and wear to the rivet heads, also the chain needs to be checked to see if there is too much side ways movement against the side plates, also the graduated lines on the swing arm of the bike or the notches on the chain adjuster cams give an indication of the amount the chain has stretched, people use a combination of these and experience to judge when they need to replace the chain the correct techniques for these types of inspection can be found with research via the net,

A point to note is that the chain and sprockets wear each other out; a new chain on a set of new sprockets will wear themselves in together and last longer, a new chain on worn sprockets will wear rapidly to match the condition of the sprockets and will also accelerate the wear of the sprockets to match the chain,

It is considered good practice to change the chain and sprockets as a set, but you can find that if the sprockets are ok and not too badly worn a pair of sprockets can last for the life of two chains, some people use two chains to one set of sprockets, but not normally the other way round,

Also a chain is a heavy piece of moving metal with a lot of inertia, so if a chain is worn and snaps or jumps a sprocket it has to go somewhere and that is normally straight through the engine casing or wrapped around the rider’s leg or locks up the rear wheel resulting in a crash, or if you are a lucky so and so it flies off the bike and lays on the road like a forlorn snake, so taking a risk with a dodgy worn chain set is a risk that can hurt,

On my bike I don’t use an ‘O’ ring chain, I use a basic 428 chain and a split link, so the care and cost of my chain is minimal, I just take the chain off the bike once a year clean the chain in paraffin let it dry and let the chain soak in some melted chain grease, lube the chain every week or so or after a particularly dirty or wet ride, this type of care has allowed the chain to last quite a few thousand miles, as to the chain itself, I buy any chain of the correct size/type from any relatively reputable manufacturer, then buy sprockets of the correct size/type to match, total cost for a sprocket chain set for my DT has cost around £20 give or take, maybe just over £25 if I cannot reuse the locking tabs,

Bikes which are more powerful and are used at higher speeds routinely have chains and sprockets that are manufactured to higher specs and with better material qualities, these chains are often ‘O-ring’ type chains that have lubrication built into the chain rollers these chains require a different type of care as the condition of the ‘O-rings’ needs to be maintained to keep the built-in lubrication in situ, so on these chains lubrication is applied externally to lubricate the contact interface with the sprocket teeth, chain rollers and side plates, these bikes often better to change the chain with the both sprockets as the chains and sprockets cost a lot more and last longer when changed as a set. The cleaning fluids and lubrication need to be chosen as per the chain manufactures recommendation, this is because the ‘O-rings’ can be chemically damaged with some cleaning/lubricating fluids. These chains can have a soft link that needs to be riveted to join the ends of the chain, and some times people even remove the swing arm to remove the chain without splitting the chain so it can be refitted,

As to adjusting the chain and the amount of free play / chain slack required on a suitably adjusted chain this is normally stated in the owner’s manual for the bike, however I adjust my bike chain to give about 1.5 inch of free play up and 1.5 inch down movement from what I judge to be the centre of the chain on the longest (normally the lower run), for motor X or off road bikes with large suspension travel they have loads of free play in the chain because of the wheel movement but they often have rollers or chain guides that control the chain tension , I then sit on the bike to check the chain does not become tight as the suspension is compressed and then check that the chain will not rub anywhere on the bike that it is not supposed to, such as the swing arm or the chain guard, I then look along the length of the chain and check to see that the chain follows a straight track from the rear sprocket to the front sprocket and that the side plates of the chain engage the teeth of the sprocket without rubbing on the chain side plates excessively, as a final check I measure the distance of the rear axle on either side of the swing arm to confirm that the centres of the axle are the same distance from the end of the swing arm on either side, a single sided swing arm is slightly different,

Disclaimer:

This is pretty much how I care for the chain on my bikes others will have other probably better suggestion and will no doubt have better and easier methods of chain set maintenance, some will also probably tell me I know nothing and am talking out of my arse. So I would read all suggestions ideas do some net research and use the best of the solutions that suit your situation, I am now gonna hide and go back in my cave and wait for the negative replies,

Hope this helps

[ozymaster]

Thanks, ill take a look at the chain at the weekend and see how much its streached

[nayruf]

Don't forget to look at the sprockets too, check out the profile of the teeth and look to see that they are not hooked or worn to sharp points and watch how the rollers engage with the teeth, do a Google net Image search for worn motorcycle sprockets there are some pretty ok pics to compare against.

[Grouch]

Personally I would just buy a new chain & sprocket set, you will get a decent ish one for around £30 just look on eBay. If a chain snaps on you you are fucked, it could even fly off and injure another person.

[drewpy]

On the XS, you get an S cable which loads up the suspension keeping the chain as it would when off the bike.

this keeps the chain tension correct, 20mm for my bike

[Silkk]

Nayruf has it about right with the method for checking chains. 

I personally run a stiff suspension setup, so only really allow for 1" play on the chain, and stick to "O"ring chains with rivet links. I'm not a fan of the split links. Unfortunately it means to save splitting the chain, whenever I want it off, I need to remove the rear wheel spindle and unbolt the brake calipers, to roll the wheel forward and out through the bottom of the swing arm. 

 

For the YBR though, it is even easier, as the engines dont put as much stress on the chain as the bigger bikes, unless your down shifting with no clutch and engine brakes like you do in a car. 
 

That being said, I would always recommend changing the sprocket at the same time as your chain, and finding your own personal preference as to the amount of play on the lower half of the chain. 

If the teeth are worn on your sprocket, replace it. If your chain is at max adjustment, replace it. There again I'm a cheap skate as the cost of my chain/spockets are triple figures  

[Grouch]

Didn't want to start a new thread because there is loads of related posts already but...............

 

I don't understand why the chains on 125's don't last me. I have done under 5000 miles and I need a new chain and sprockets set. People all say that that can't be right and I should be getting over 10K miles before needing a new one. The same thing happened on my XT and now it's happening on my WR. I do ride the bike hard but I always lube it and look after it not obsessively but I don't neglect it. What am I doing wrong?

[nayruf]

Hi

Do these chains need replacing because they are worn, rollers/side plates/rivets and do the sprockets show signs of wear, or are the chains being replaced because they have reached the limit of adjustment, if it’s the latter could these new chains be too long and have too many links to start with. When the chain has been replaced did you have to slack the adjusters back to the beginning of the scale?

Just a thought

[Grouch]

The problem is the chain just stretches and I have to tighten it every few weeks up to the point where there is no space left on the swingarm for the marker plates to go.

[slice]

Thinking about what you said Grouch and was wondering if it's because your buying cheap chains? They do stretch a bit but should last a year or two without dangling down on the road. D.I.D chains are £60+ quid a set but cheap ones are only about £30+, try an expensive one and see if it gives you more life, sometimes you pay twice as much but get 3 or 4 times the life out of a chain.

[Grouch]

I tried the more expensive heavy duty ones and the one that come on the bike new was crap. I'll buy another good quality one this time spending more money but I doubt it will make a difference. It must be how I'm riding it.

[Grouch]

Today I got new a new chain and sprockets set fitted. I decided to spend a bit more this time on a better quality one (£50). It looks the part and you can tell the difference in quality just by looking at it. Anyway as you all know I have bad experiences in the past with garages who are incompetent, dishonest and greedy. Anyway took my bike to a garage half a mile up the road, the guy has been there since 1974 so that was a good start. Everything went fine he did the job and had my bike ready when he said he would. When I picked the bike up he spent some time with me giving me advice and it turns out I have been adjusting my chain wrong! He explained to me when I tighten it up before I check the slack of the chain I need to sit on the bike first. I didn't know that when I sit on the bike the chain tightens! So after all this time I know what I have been doing wrong. 

[blackhat250]

Yip grouch"o  . need slack,  I think Honda HRC,  thought they could change this law of physics , by  pivoting the swingarm inline with front sprocket .  to achieve constant tension  . but na ,,,,,,

[Grouch]

Hopefully that was the reason my chain kept stretching. Thinking about it now I'm really lucky none of my chains snapped. It must of been stupidly tight once I'd tightened them up.