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jsaunders
11-04-2002, 08:16 PM
put on doubles today for mulching /bagging leaves and had to turn up the rpm. The mower was down 300 rpm's. Do you notice this alot or is it not a problem on larger hp machines. This was on a 15hp 52" hydro w/b.
Thanks Joel

MATTHEW
11-04-2002, 08:19 PM
I noticed a real drag on my 15HP Kohler.

Took them off the next day.

jsaunders
11-04-2002, 08:27 PM
I want to mow with the machine for a day with the doubles on and see how it goes. I mowed some of my side lawn- ran over it 2 times and really mulched up the leaves pretty good, and they were wet. I might just go back to single gators if it's to slow.
Joel:p

John DiMartino
11-04-2002, 08:39 PM
Doubles on my Dixie pulls the 25 hp down about 100 sitting still,as soon as it hits grass,its down abot 300 rpm,you cant egt it back by rasing the governor,its just out of power,in my case,I set mine to 4000 for a while with doubles,it still dropped below 3400 in no time.

jsaunders
11-05-2002, 09:03 PM
Did 2 lawns today and took off the doubles and just went with single gators much faster. Need those rpm's up to mulch those leaves.

PaulJ
11-05-2002, 09:45 PM
I think 15hp is a little low for a 52" cut. I run doubles on a 14hp 36" lesco and give up some rpms in Ideal conditions. latley leaves and sutting 1/4" shorter have realy given the 14 a work out. :p

I still like the "dust" the doubles make:D
I have run doubles on a 52" with a 20hp and had no problem

Doc Pete
11-05-2002, 10:45 PM
Originally posted by jsaunders
put on doubles today for mulching /bagging leaves and had to turn up the rpm. The mower was down 300 rpm's. Do you notice this alot or is it not a problem on larger hp machines. This was on a 15hp 52" hydro w/b.
Thanks Joel

My 48 with a 17 kaw doesn't like mulching with doubles. Cutting is fine, but once you start really chopping things up the 17 starts has it's hands full. 15hp on a 52" deck is just too much on the engine....... IMHO.................
Pete

rodfather
11-06-2002, 08:05 AM
Originally posted by Switchless@aol.com
My 48 with a 17 kaw doesn't like mulching with doubles. Cutting is fine, but once you start really chopping things up the 17 starts has it's hands full. 15hp on a 52" deck is just too much on the engine....... IMHO.................
Pete

I agree with Pete...15hp ain't gonna cut it (excuse the pun) on a 52" deck (especially with doubles in thick/wet leaves). We run 17 and 18's on our 52"s. And there is a noticeable drag when they have double gators on them...we just go a little slower.

What you lose in speed you make up for by mulching the leaves more with doubles though.

just my 2 cents.

Doc Pete
11-06-2002, 11:40 AM
Originally posted by rodfather
What you lose in speed you make up for by mulching the leaves more with doubles though.

just my 2 cents.

Sounds good to me. FWIW, after playing with blades and the need to double cut with doubles, I noticed the biggest thing that steals power is the "sail" on the blades. I had cut off the sail on one pair of blades, and ran one set of highlifts, and one set of "no sails", and the motor practically didn't know it had an extra set of blades. So, IOW, you might try using the "stock" gator mulchers, and stay away from the "magnums mulchers". Since you are mulching, the sail won't help much because you aren't trying to blow the debris out the chute.
Just my "two" sense ;) ;)
Pete

Envy Lawn Service
11-06-2002, 08:06 PM
Out of all the double combos I've ever tried, the one I put on today is the only one I could notice a difference with. DOUBLE HIGHLIFTS with a mulch kit. When you get in thick high stuff the highlift foil really puts a load on the engine at 2 per spindle. I guess its because they catch so much wind and clippings. When all those clippings are up under the deck with nowhere to go and keep getting picked back up what can you expect though?

Also they were 2 different styles. I did it that way on purpose so the cutting edge of both blades would be perfectly even. Dunno if that made any difference or not.

awm
11-08-2002, 08:06 AM
with my 20 command the rpm goes from 3750 w singles to 3860 w doubles.
somebody on here explained it as the governers calling for more power as the load increased. i guess its how the carb is adjusted.

John DiMartino
11-08-2002, 05:24 PM
Awm,your findings are 100% backawrds from what they should be,that is very strange.The governor does not sense load directly,it can only sense engine speed,it is a basicall simple device,comprised of springs and weights that act on a fork,or lever,depending on the system.if you RPms are set for 3760 with singles,they cannot be higher with doubles,unless you are pulling harder on the spring(throttle lever).There is no way it will rev higher with a bigger load than a smaller one,unless the governor is computer controlled or you move the throttle furthur.

Ryan Lightning
11-08-2002, 07:38 PM
How are you guys measuring RPMs:confused:

John DiMartino
11-08-2002, 10:01 PM
Ryan,I use the digital Tinytach,or Sendec tachometer/hr meters. They are 30-60 bucks,and they are necessary ,IMo. The factory never sets the governors right on 90% of the mowers.My Dixie came set a 3360 RPM, max,and it had a tach,so it was easy to see it was off. A lot of cutting,overheating ,poor performance problems can be traced to incorrect max Governed speed,usually to low.