Above is a Google Earth image of Goodyear lake from the Portlandville  Bridge to Colliers dam in Colliersville NY. The road going around the lake on the left side of the photo is Route 28. The Portlandville bridge is at the very top of the photo. 

Colliers dam is at the very bottom of the photo perpendicular to Route 28.

Looking downriver from the Portlandville bridge. Just a couple hundred yards south on Route 28 there is a public access to the river.

This is the public access to the river just south of the Portlandville bridge. This body of water is just a little inlet. The Susquehanna is up ahead. 

It's a good idea to have a compass. I'll explain why later. 

Mile 21.5;  Time 12:05PM

That's me, paddling out of the public access inlet to the river.

Me again on the river after having made a right turn into the river from the public access inlet.

Here the river widens into Goodyear lake. It is very easy to lose the river channel here and if not careful you could end up into a dead end where you would have to turn around and paddle back.

At this point you will be heading West. If you keep this heading for more than 5 minutes you have passed the entrance to the river channel and will end up in one of the dead ends.

You should hug the left bank and turn south (left) with the contour of the land. If you follow the countour of the left bank you will then start heading east. It is somewhat counter-intuitive because it appears that you are heading into a dead end, but if you keep going for a couple more minutes you will see that you are entering the river channel.

 Don't worry if you go down the wrong way into the dead end. I went down to explore and was able to see that it was a dead end after only about 10 minutes from the point where I should have taken the left. In all I lost about 20 minutes.

A view of the upper part of Goodyear lake shortly after entering the river from the public access inlet. Hug the left bank and follow to the left (south), and then east.

If you pass this house you've gone too far. 

Entering the river channel. Here you should be going due South, and a little while later you will be turning south west. 

The river channel opens up into the southern portion of Goodyear lake. Here you should cross to the far side and continue by keeping the bank on your right side. 

Mile 24. Up ahead is the Knott's motel and marina. Just before the marina is a public access boat ramp.

Time 1:05pm It took me only one hour to reach the boat ramp at Knott's motel. This spot should be a good place to target as the end of the first day of paddling. I think that a fair paddler can make the trip from Cooperstown to the Knott's motel in about 7 to 8 hours. Here there is also a Red Carpet motel (located up the hill above the Knott's motel on route 28.

The Knott's motel or the Red Carpet (just behind the Knott's motel) would make great places to spend the night (if you don't like camping out). The next day you could portage around Colliers dam and make Bainbridge NY your target for the second day.

The public boat launch at the Knott's motel. Colliers dam is downriver about 200 yards on the right (not visible in this photo)

Approaching Colliers dam. This is only a few minutes paddling from the Knott's marina. There are floaters and a rope stretched accross the river. You definetely do not want to go past this point. 

The portage to go around the dam is on the left side 

Looking north at Goodyear lake from the portage. 

The portage around the dam is about 650 feet. The first part is uphill; I think about 150 to 200 feet. 

A view of Colliers dam from the downriver side 

The downriver side of the portage at Colliers dam 

 Below the Colliers dam the Susquehanna runs free again. The current is pretty fast, but easily navigable (no white water).