Looking for a little more speed

[cschannuth 3,795]

Hello all.  I'm new to the forum and have my Dad's 1978 C-161.  How can I increase ground speed?  I don't want to race the neighbors or anything but I cruise the property with it.  I don't mow with it but use it to move trailers, pull a lawn roller, pull spreaders, etc.  It's in really great condition and everything works but ground speed is pretty slow.  Plus, as you know, Low range is really slow.  Thanks for any help and I hope I put this in the correct section of the forum.

Edited April 11, 2016 by cschannuth
Grammar error

[daveoman1966 3,610]

To increase the ground speed, either make the ENGINE pulley larger, or the TRANSMISSION input smaller, or BOTH.  I just listed a 4" diameter TRANSMISSION input pulley that MAY get you there.  Check the size of your transmission INPUT shaft as the pulley I have listed is for 3/4" shaft.

my ebay listing is number: 131777881327.  You can see more details there.

[cschannuth 3,795]

The pulley on the transmission is 6 1/2" in diameter and it looks like shaft is about 5/8".  I assume the 4" pulley would've made a noticeable speed difference if the shaft had been the correct size.

[Pullstart 59,644]

4" vs 6.5" on the driven pulley would yield a 63% increase of speed.  That should help!  Here's a link to some pulley math to base my figures on...

 

[cschannuth 3,795]

That should do nicely if I can find the correct pulley.  Thanks!

[953 nut 51,627]

      You should be able to find what you need at WW Grainger or McMaster-Carr on line once you have determined what size will give you the desired results.

[Retired Sparky 526]

     Try Surplus Center. I just found a single sheeve 4.25'' x  5/8'' bore  for $12.50.  I didn't look but you might also try Fastenal.

[cschannuth 3,795]

If I get a smaller pulley do I need to get a different belt or is there enough adjustment to handle difference in pulley diameters?

[daveoman1966 3,610]

Here is an on-line tool to help with PULLEY diameters and relative Pulley RPM.  You can change size of either pulley and see the resulting RPM of each. 

There are lots and lots of other informative things here too.

http://www.blocklayer.com/pulley-belteng.aspx 

[cschannuth 3,795]

Thanks for the link.