Clean gutter downspout

I don't know if they still sell this,and it would only work if he blockage was complete. And it was designed for sink drains,, not downspout s, and I don't know if it it worked. (So am I in the clear now?)

But they had what looked like a rubber ball around sound water source,, maybe it went around a garden hose? and somehow it inflated or was big to begine with when in use, so the water couldn't come out backwards, it had to force the clog through.

And it might work only with round pipes not rectangular ones. Oh, never mind.

I've got two down spouts on my garage that get clogged with leaves/twigs. They each have

In my old house I always used a garden hose from the gutter opening, which always seemed to work. BTW they to have a small nozzel that shoots a straight forward hard stream to break up clogs. I never seemed to need this; only the hoze with no nozzel, just running water. As I now live on the side of a mountain, my downspouts feed an underground pipe which comes out in a lower area. When the pipe wouldn't take water, I tried the hose thing. I couldn't get through the "clog". Well, it wasn't a clog, it was a crushed pipe which apparently happened years earlier when the house was being build and trucks pounded over the area. It a few years to show up. I hired a guy with a jetter. Of course, he couldn't get through either. So, I hired a guy to dig. Luckily the drive had yet to be paved. He found the crushed pipe. Now the driveway is paved. BTW, you can buy jetter attachements for a power washer. I bought a 'set' on Amazon for under $50.

Maybe I can refine what I should be doing.

What if I created a clean-out halfway up? In the length of straight pipe, where it is easily reachable, and I could snake in both directions? Sewer lines always have cleanouts.

Is there a product like that? When we lived in Germany water was super expensive, and most downspouts had a gadget in the straight section that pivoted out 30 degrees. When in (straight down) rain water ran down the pipe to whereever it went. But pivoted out, it blocked the pipe and diverted the water to a rain barrel for irrigation use. Everybody had flower gardens.

I got this:

On Fri, 7 Aug 2020 06:41:38 -0700 (PDT), TimR posted for all of us to digest...

If you are getting enough shingle particles to clog it up you probably need a new roof. I'm not there and can't see it but sorry for the bad news.

As for the clogging I never had it so the other posters have more knowledge.

We just did the new roof this summer, so there should be no more granules for a while.

I always thought a new roof shed more granules during the 1st year than after that????

Yep. Noticed that on my new roof.

From what I've been googling it seems my problems would be much less if I had larger downspouts and larger drop outlets.

Any opinions on the funnel style outlet vs the traditional oval drop outlet?

there are several funnel style like this:

Couple of years ago when I got a new roof and gutters and downspouts, the contractor put in larger downspouts. Did not help with clogging at the top. I put on gutter guards with micro mesh screens and they are working well.

Either one might solve your problem.