Rear Wheel "catches" every 3rd turn...

[Guest]

Or maybe it's every 4th revolution.

Either way, I've been getting horrible mileage (20-25 MPG) even after adjusting the carbs. Today I've noticed a strange rhythmic scraping sound coming from under the bike when slowing down for stop lights. When I got home, I gave the rear wheel a few turns, and sure enough, it catches on something every 3rd or fourth revolution. I don't know what it could be...

And I'm not sure if this has to do with the problem, but the chain seems to be making excessive noise (or not, what do I know).

Any ideas? I'll check the rear brake, to make sure it isn't dragging, but if it was the brake, wouldn't it drag continually, and not every few revolutions?

[Agemax]

the rear wheel rotates approximately once for every 3 revolutions of the front sprocket, if your chain is making excessive noise then its a sure bet it is knackered, along with the sprockets. you probably have a seized link which is catching on something behind the front sprocket cover.

remove the cover and spin the wheel, see if you can see anything there.

[Larry D]

Yes...sounds like it's time to give the rear-end a good inspection.......that didn't sound right....

[AX2007]

the rear wheel rotates approximately once for every 3 revolutions of the front sprocket, if your chain is making excessive noise then its a sure bet it is knackered, along with the sprockets. you probably have a seized link which is catching on something behind the front sprocket cover.

remove the cover and spin the wheel, see if you can see anything there.

Thanks man... I'll give it a shot. Obviously if the sprocket is catching, this would definitely contribute to my crap mileage, correct?

[Agemax]

Thanks man... I'll give it a shot. Obviously if the sprocket is catching, this would definitely contribute to my crap mileage, correct?

chain and sprockets in a very poor condition will cause bad mileage, loss of power and lots of horrid noises. you MUST replace both sprockets and the chain as a set. also if it is catching somewhere, it could be wearing a hole somewhere, either the cover or the crankcases. investigate immediately

[AX2007]

chain and sprockets in a very poor condition will cause bad mileage, loss of power and lots of horrid noises. you MUST replace both sprockets and the chain as a set. also if it is catching somewhere, it could be wearing a hole somewhere, either the cover or the crankcases. investigate immediately

If I'm replacing everything, should I go with a 530 chain and sprocket?

[Agemax]

If I'm replacing everything, should I go with a 530 chain and sprocket?

that would certainly be your best option. cheaper, stronger,quieter and lighter.
cant go wrong really...........

[81ZUKI75]

that would certainly be your best option. cheaper, stronger,quieter and lighter.
cant go wrong really...........

++1

I converted my T two years ago and was amazed how much smoother it was than my E with the 630 . I went with an X-ring chain, 18T front/50T rear sprockets and don't forget the 6mm thick spacer washer you'll need for the front. I got everything I needed from Z1 and just ordered the exact same setup for my E model...parts due tomorrow

[MAC10]

530 chain is also smaller, and less likely to catch or wear on something.

[AX2007]

Thanks guys... I'll have to order that stuff from z1 this weekend. Is there anything I should keep in mind when changing the chain? Tips, pointers, anything?

[Nessism]

Pull the swingarm maybe and lube the bearings?

[MAC10]

Order a spare master link or two, if the chain uses them. 530 is of course its own size. If you have a chain breaker tool, and a press for installing the master link it could be handy if you need to remove links if the chain is long. Careful ordering, especially from Z1 should prevent this. Doesn't hurt to ask them when you order to be sure.

[AX2007]

So I took the time this afternoon to remove the cover and see what there is to see... and this is what I found:

[Agemax]

nothing obvious to see. did you spin the rear wheel to see if you could hear the clicking noise with the cover off?

[AX2007]

So a couple of things I found: When I tightened the chain, the problem got worse, the tire would barely spin. When the chain was loosened, it was less noticeable, but still there.

Another thing I found: The manual I downloaded from BikeCliff's site said that for GS750 16 valve I should 383mm for every 21 rivets or points (whatever). I have about 22. I'm guessing the chain is very stretched and worn?

Sorry for all the questions, I'm just trying to learn this stuff.