Chain/sprocket replacement time, want to make sure I get the right stuff

[Watevaman]

 A recent cleaning of my chain revealed to me that it's not in the best condition. It's got about 8,400 miles on it but I'm willing to bet it's the same chain that was on the bike when it was produced in 89/90, so I figure I'll spend the money and replace all the drive parts so I don't have to worry about it breaking. I'm still not 100% on what to buy though, so I thought I'd ask you guys to make sure I'm getting the right stuff for the job.

For the chain, I've thought about the EK 520 SRX. Is this the right kind of chain for the GS? I know the stock length is 110 links so that's what I'll order if this is the right measurement. I looked into EK chains and it says they have a special master link that doesn't need any special tools, but I can't find if the SRX uses this type or if I'll need to pick up a chain tool of some kind.

For sprockets I was a bit more curious. I was planning on going with a 16/39 combo but I don't know if a 15 front would be worth it. I'm assuming these two will fit the GS as well?

JT 520 front
JT 520 rear

If I do decide on a 15 front, would a 110 chain still work ok or would I need less links?

Thanks for the help.

[adidasguy]

520/110 is right

15t front same chain. It is only 1 tooth different i.e. 1/2 a link so same 520/110. If that's not right, then I have no idea why my bikes work. I have 15/39 on Junior and Suzi. Stock 16/39 on Phenix. All have 520/110 chains.

15 front gives a little better low gear for slow traffic. Less need to drop down to 1st. Can stay in 2nd more for slow traffic. The change from 16 to 15 is only a 1/16 change in gearing... or a 6.25% change.

[DaMuffinMan]

Scroll down a lil bit and look to the left of the same page you posted a link to.

http://www.motorcycle-superstore.com/14/71/969/10839/ITEM/EK-520-SRX-Chain.aspx

That's the master link that doesn't need a riveting tool.