now I have owned my bike now for about 9 month now and have done a lot of modification and maintenance to include several chain lubing but have never noticied this until today while doing my maintenece.

I havnt checked the front sprocket but apparently my chain is a 530 and my rear sprocket is a 520 now I can't imagine this is a good thing seeing that I can slide the chain from left to right on the sprocket but its not loose so I don't worry about it poppin off the sprocket.

I know the front sprocket is -1 tooth but I didn't check to see if its a 530 or a 520.

how dangerous is this?, I know its not the ideal set up, I have put about 3k miles on it this way, no problem as of yet.

 

Not a good thing like you were saying, it's holding up now but I'll bet you're getting accelerated wear & tear on both chain and sprocket.

 

What he said...

 

I'd imagine so but the chain and sprocket both appear in great shape, no excessive wear that I can see on either. I keep the chain lightly lubed so I can inspect it easier.

 

well I checked the front sprocket today when I changed my oil and its the same as the rear.

I have just started doing my own maintence and I took the bike in to a shop prior to me buying it and its been to at least 2 other shops for minor but something I didn't know how to do and for a rear tire and no one noticed the chain and sprocket size!

 

Not something they'd really look at unless they were replacing it. Having the rear tire done should have been a time to notice it, but maybe the guy did and just blew it off as some squid trying to do his own maintenance and screwed it up.

 

The 520 conversion is lighter and sprockets are usaully aluminum, wieght savings
the 520 sprockets are 1/4" thick compared to the 530 being 3/8" thick and made of steel.

your problem with running 530 chain 520 sprockets is the 1/8" extra gap between the links will eventually cause the chain to wear more to one side and fatige the chain for excesive wear marks or even failure.
If you ride normal it should last fora long timeon the other hand if you ride aggresive and pop wheelies your most likely going to snap a link or throwthe chain because the shear point will be located to one side of the chain instead of evenly on the linklike attended.
plus preety sure the guy before you didn't know the difference and just went with the cheaper sprockets out of the book.