The pics

[attachment deleted by admin]

[attachment deleted by admin]

Please comment on the rear brake caliper, front tyre, gasket and chain condition 

And my chain rubs on the rubber supporter thingee near the front end above the gear box cover, sorry for lay man terminologies 

[attachment deleted by admin]

You need new tire. Cracks are bad. Tread worn. Looks like very hard rubber. I would guess your rear tire is bad, too.
Chain does lay on the plastic chain guard but your chain looks very loose. Check the chain tension.
Pictures too small to really see them.  144x256 pixels is too small to see any detail.

@adidasguy, you are always ways to the rescue 
Snaps I took ate like more than 1megs each trying to compress/change format 

That's my tear brake caliper. What's missing there? Its not a normal looking brake. Got it as it is...

[attachment deleted by admin]

You're missing the black plastic top cover.

M not so sure but aren't some pin thingees in between brake pads also missing?

looks like they replaced the pics with screws. items 6 and 7

[attachment deleted by admin]

+1 @tcmia. Looks like m missing 5,6 and 7. Daiiimmmnn :-/

I would suggest going to ebay and order a used rear brake from PinwallCycle. They are good on parts. Look at the pictures and get the newest one with the most pads. Pop that on and you're good to ride. (I buy all my brake calipers with nearly new pads from them). Cost is $14.95 to $24.95 - cheaper than buying pads and figuring out what parts are missing.
You might do the same for the front if your front pads are worn.

http://stores.ebay.com/PinWall-Cycle-Parts-Inc/_i.html?_nkw=gs500+brake+caliper&submit=Search&_sid=12458664

Hmmm.... I don't know where you are but by the pavement under the bike I would guess Europe - maybe Germany?

OK. I see you're in Pakistan. That may make getting parts difficult. Still, if you can get a complete one in good shape that might be better than trying to put in missing parts. If parts are missing, you don't know if it works very well.

I hope you don't ride like the YouTube videos of the "Pakistani Biker Boyz". They are real crazy!

Quote from: bremsstrahlung.positron on October 22, 2013, 10:42:04 AM
That's my tear brake caliper. What's missing there? Its not a normal looking brake. Got it as it is...

Anyone prepared to bodge anything connected with the braking system needs a kick up the ass. Think about what could happen if one of those capheads was to come loose and drop out.

You need to carefully check every part of that bike.

Quote from: bremsstrahlung.positron on October 22, 2013, 11:53:00 AM
+1 @tcmia. Looks like m missing 5,6 and 7. Daiiimmmnn :-/

Wow! #6 was replaced with a bolt! That is so wrong. Get a replacement caliper. I would not trust that one. Brakes are very important - don't risk your life with a caliper that has been improperly repaired.

@sledge @adidasguy. Wilco sir, m on it.
Getting a whole new rear brake caliper.
Man does it suck to be in such dearth of spares here :-(

@adidasguy the biker boys have no regard for their safety or others here.
Its wild wild west. Mayb a bit too wild :-/ :-(

That caliper with the hex head cap screws replacing the pad retaining pins looks like a clever fix to me for someone located where parts are scarce.  Good to see there are still some good shade tree mechanics left around the world, they are almost extinct here.  I wouldn't loose a nights sleep over that one, but I'd make sure those cap screws were tight from time to time.   

I wouldnt assume anything. They could have been `hammered in` for all we know 

Quote from: adidasguy on October 22, 2013, 12:09:37 PM

Quote from: bremsstrahlung.positron on October 22, 2013, 11:53:00 AM
+1 @tcmia. Looks like m missing 5,6 and 7. Daiiimmmnn :-/

Wow! #6 was replaced with a bolt! That is so wrong. Get a replacement caliper. I would not trust that one. Brakes are very important - don't risk your life with a caliper that has been improperly repaired.

^^^ that's the truth ^^^^^

and people can you tell me the year of make of my bike?? papers say it an 01 but i doubt it. actually it was an auctioned bike, used previously by highway police or something... pic is attached

[attachment deleted by admin]

If the papers say '01, then it's probably an '01 frame. If you can find the VIN of the frame, you can have a dealer check it, or perhaps Google. The motor could easily be newer if the PO switched it out. The only way to tell is a plate or some identifier on the motor.

Or I could be completely wrong lol.