Troybilt Bronco will not go fast

[Sherrym12]

I have put new drive belts on, checked all the pulleys, made sure all connections are correct, talked to service people and apparently I'm not the only one to have this problem! My brother is a great mechanic and even he can't figure this out! HELP!!!! This tractor mows great, but with a huge yard, almost an acre I need speed!

 

[Bob E]

Are you using OEM belts? I know it sounds dumb at first but MTD makes their belts different than the rest. Also their older owner's manuals always had instructions for adjusting belt tension, but they leave that little piece of useful information out of the newer manuals.
Here are a couple pages from my '99 660 owner's manual for reference.

I think your tractor is like the one in this manual?
http://service.mtdproducts.com/Training_Education/769_06667_700_series_riders.pdf
If so check out page 43. Obviously creep is the opposite of slip :thumbsup: