chain slack

[Lorenzo]

I was taking care of the chain adjustment, when I noticed that (turning the rear wheel by hand) the chain, at a given degree of rotation becomes really tight, and after turning the wheel a few degrees, it become slack again;
It's feels like having an oval sprocket;
I dropped the bike once and ended up with a bent gear change lever;
Could it be a bent output shaft?

thanks

[jabcb]

Had something like this happen to my T500 last year. Bike shop said the chain had developed hard spots.
Replacing the chain & sprockets solved the problem.

[Alan H]

Take the chain off and see if it has any tight spots. Spin the back wheel and make sure the sprocket spins true and doesn't spin 'oval'. Then the more awkward bit, take the sprocket cover off and check that too, then you're certain what it is. Remember that the drive sprocked is smaller than the rear wheel sprocket so if the gearbox shaft is bent there will probably be three tight spots as you turn the rear wheel one revolution.
Just a thought - check the rear wheel sprocket looking from the back of the bike when spinning the wheel - it couldn't be a slightly bent rear wheel axle bolt could it?

[Lorenzo]

At a closer inspection, traces of rust were spotted, the bike has been out of use, for quite some time now, and I must admit of having neglected the routine oiling-up, so there you are;

While I was at it, I took the measurement of the 21 pins, and I got 320,7mm instead of the 319.4 service limit;

I will check the output shaft for trueness when I'll replace the sprocket;

thanks very much

[pearljam724]

Like jabcb somewhat said. The chain has tight spots in some links because it has lost its flexibility in some areas due to lack of lubrication, rust and dirt around the pins and side plates. You could try soaking it in a tub of oil and it may gain that flexibility back. By the sound of your descriptions. I would just buy a new one. Get in the habit of cleaning and lubricating the chain every 600 miles. You especially have to stay on top of maintenance with non oring chains. It does a lot for the chain, suspension, sprockets, traction, etc. Not to mention your wallet. Chain maintenance is the most important maintenance part on any motorcycle. Yet, it's the number one neglected part by many owners.

[GT750Battleship]

Good advice,keep them clean,lubricated & adjusted & you'll be rewarded with smooth running,you also loose horsepower with an unloved chain,always replace the chain & both sprockets together.

Regards,
GT750Battleship.

[pearljam724]

Good advice,keep them clean,lubricated & adjusted & you'll be rewarded with smooth running,you also loose horsepower with an unloved chain,always replace the chain & both sprockets together.

Regards,
GT750Battleship.

Chain maintenance affects a lot of aspects. Fuel mileage, tire wear, acceleration are others. The most important is traction. If the chain is not doing it's job correctly. By not being adjusted properly, clean and lubed. The suspension will be negatively effected. A smooth ride is one factor, but also traction is taken away because the suspension isn't free to do its job. Taking into account that the suspension is set up correctly also for weight of rider, speed and a specific terrain. The chain pretty much acts like an additional shock if adjusted proper. It works in harmony with the shock absorbers. swingarm and tires. To keep the tires planted to the ground. Depending on speed, road surface and a few other factors . One can't work properly without the others being correct and trouble free.