accelerator pump diaphragms

About 9 months ago I got a 79SR D2. I started it up and took of down the street, then started to lose power and eventually died (about 3/4 mile away). Instead of diagnosing the problem there, I tore the bike completely apart for restoration.

I'm now at the carbs, and they are completely spotless to my suprise, you could eat soup out of the bowls.

But I noticed that both of the diaphrams in the #2 accelerator pump are in bad shape. Both are pretty brittle and cracked.

Would these diaprhagms cause the problem I mentioned above?

Or do I have other issues I should investigate?

here's some background:
-the previous owner hacked off the back of the original pipes
-I checked valve clearances and made the necessary adjustments
-not sure of my compression situation.


I know there are dozens if problems that could cause it to run poorly, but do the symptoms I mentioned match with crappy diaprhagms.

thanks!

I am surprised you didn't pm me. The accelerator pump would only affect take off and not necessarily while riding. Check your vacuum actuated petcock. If you ride your bike with it in prime sometimes the vacuum side fools around, Put it on prime and you have go!