Chainguard hitting rear wheel

It's a shame that I can't figure this one out. I started hearing a scraping sound, not metal to metal, so as I arrived back at the garage I checked the rear, realized my chain was quite loose so i adjusted to give 1 - 1.5in of play. I noticed that the chainguard has been rubbing against the wheel and I can say with confidence that this was not this way before. After adjusting and lubing the chain, I tightened the back up and removed the chain guard.

Does anybody know the reason for this occurring and how I might correct this?

 

Doh! I never checked the alignment...

I am still getting a series of strange jerks about a second apart while riding. I have adjusted the rear breaks, alignment and chain. The sprocket seems to be in good condition and the chain is sufficiently lubricated.

Any help?

 

What size rear tire are you running, I had problems when I was stoopid and decided to put a 140 on there. Now the only rear I would put on there is a 120.

DOOH yup not having the rear aligned is just like riding your dog, the rear is always over to one side Get the rear end equal and everthing should be better.

As for the jerks, put your bike on centerstand and find the masterlink. When you get to the masterlink check for play. Now at each half rotation of the rear wheel check for play. Sounds to me like you have an unevenly stretched chain and the only cure for that is a new chain and new sprockets. If you go out and get a billion dollar chain and do not replace the sprockets your chain will wear out very quickly. You need to replace both sprockets and the chain for long life of the chain.

Good luck

Sean

 

Hmm I can't be sure what size the PO has on there... I'll check that later.

I suppose I need to replace the chain and sprockets as at a certain point, the play on the chain is dramatically reduced. Do you have any recommendations as to where I can get a good deal on these?

Thanks for your help, I really appreciate it!