Speed up pulley for the deck

[nicky1]

I was reading some of the old posts on another site about speeding up the deck to cut better.Some of the commercial zero turn decks really zing.
I have a 44A deck on a 108 Cub. I came across a pulley in my saved junk that is a 4 1/4" over a 4 1/2. The original was a 5" over a 4 1/2. Has anyone used a pulley like this to speed up the blade speed? It looks identical to the Cub pulley and I think it came off a MTD deck of some sort

[ksanders]

I do it on every 44/50" deck I've had. I also install mulching blades which seems to help a little more. It's always been a task for me trying to keep those decks cutting thoroughly while going fast.

[nicky1]

Thank you for the input. I am currently rebuilding a 108. I haven't got to the deck yet but was kind of searching ahead. I think I'm going to try the smaller pulley... nothing to lose.

[BearKiller]

I am so glad that you started this thread, as the same thoughts had been going through my poor over-taxed head.

I guess I could research all the pulley diameters and do the math; but, does anyone know a close estimate of just how much faster the blades will spin using a 4-1/2" pulley as opposed to the stock 5" ?

Contrary to common belief, rotating assemblies run smoother, quieter, and more efficiently at higher speeds.

Consider a tire that has a separation or twisted/broken belt; the tire usually will level out and run at high speed, yet shake your teeth out at 40-mph.

I have a two-cylinder diesel tractor with a belly-mower and two-speed PTO; 540-RPM and 1000-RPM; everyone warns me not to use the 1000-RPM; however, I have done it problem-free for years; everything about it performs better at 1000-RPM than 540-RPM.

The same goes for bush-hogging; whether little play-around toy tractor or big wheel-horse 4320 turbo John Deere, the bush-hog performs best at the higher PTO speed.

I would like to know more about this pulley-swapping procedure.

Thanks for reading.

[BearKiller]

I was reading some of the old posts on another site about speeding up the deck to cut better.Some of the commercial zero turn decks really zing.
I have a 44A deck on a 108 Cub. I came across a pulley in my saved junk that is a 4 1/4" over a 4 1/2. The original was a 5" over a 4 1/2. Has anyone used a pulley like this to speed up the blade speed? It looks identical to the Cub pulley and I think it came off a MTD deck of some sort

Do you know what the bore diameter is of the 44a deck pulley ?

Thanks.