By terry harrison (Th3) on Unrecorded Date: Edit

im looking for ideas, information, or actual plans for gearing down a max iv. has anyone geared their max iv down? know of anyone who has? i did a search and only found some questions, but no ideas or solutions.
going to smaller tires is out of the question.
a clutch kit is not what im after.

im toying with the idea of making a jackshaft to mount on the frame, over the shift shaft.

i appreciate any input, fellas.....

By Timothy Schotanus (Mudbuster) on Unrecorded Date: Edit

I had thought about it a while back. A dificult problem on the max4. Are you looking for more low end power or more pulling ability or is it you want to slow the machine down, maybe for the kids to learn on without killing themselves? I wanted more low end power for mudding and such and I found that more power out of the engine solved it for me with no change in gearing. I now have 30+ HP and even with tracks on I have no power problems.

By terry harrison (Th3) on Unrecorded Date: Edit

i have had a problem with low end power since day one. i corrected some problems i that i have had with the machine since i bought it. i just finished going through the carb, gas tank, and fuel lines. it sat up for a while before i bought it, causing the gas to go bad on top of having trash in the tank. i also had to add spacers under the motor to get the belt adjusted because it was so loose. everything is now working as it should. the engine used to bog really bad when i got the machine in a bind. now that everything is working right it doesnt bog nearly as bad, but thats not good enough. i just dont want any bog at all. the machine seems geared too high(or short on hp) for what i want. i like to ride aggressive and find myself wanting to put more power to the ground. i never really thought about hopping up the engine, i guess because its so new(50 hours). what engine do you have and how did you increase the power?

By shane forsythe (Shanefor1) on Unrecorded Date: Edit

terry,
max are not the only ones who made the t-20 shifter , talk to richard clark he has rebuilds and may know of one built with more power,

if an older 6x6 had a smaller horse power/ torque chances are it had more powerfull gearing to makeup forlack of engine power,

2 strokes in paticular as they have lower torque ,(this won't apply to racing 6x6's as they're geared for racing).

generally the way to tell if the box isn't in the machiene is:
for power a smaller (than usual) driving gear , and a larger driven gear.

for speed a larger (than usual) driving gear and a smaller driven gear.
you may of know that but done for the benifit of others that don't.

also you could add an extra shaft (and weight) with another set of sprokets to gear it down.(it doesn't have to be done in the t-20.)
hope this helps shane.

By Attex Bob on Unrecorded Date: Edit

Terry, make sure you Max is jetted correctly. It will make a world of difference in performance.

By terry harrison (Th3) on Unrecorded Date: Edit

bob,
its jetted from the factory. i havnt changed anything.

By terry harrison (Th3) on Unrecorded Date: Edit

i searched for 4 hours last night on the net and found nothing. i guess nobody makes artermarket performance parts for the 25 hp kohler command. i did find some briggs stuff and alittle kohler flathead single piston stuff for the garden tractor pulling sport. i also found a 26 hp kohler command pro with factory electronic fuel injection. it has full computer controls and guages. cool. found it at the kohler website. looks just like the 25 hp thats in mine.

anybody know of any person, catalog, place, web site, state, country, continent, planet, galaxy, or solar system, that has aftermarket performance parts for the kohler twin?

By Attex Bob on Unrecorded Date: Edit

Thats exactly what I'm saying. The factory can only jet for one altitude. They don't jet one for lets say L.A. and another for Denver. If your hot and high or cold and low your going to more than likely have problems.

By Howard Hoover on Unrecorded Date: Edit

You could buy one of those 30HP Generac V twins and tell us how it does.

By terry harrison (Th3) on Unrecorded Date: Edit

after a week of searching i have only found one web site with high performance parts for the kohler command twin. oh yea baby! i found performance parts! but after seeing the price i decided to try the clutch kit first..... im told the kit will give me a stall of around 2200 rpm. that should bring up the horsepower @ clutch engagement to make me happy.

if it doesnt......................

stroker crank.................-$475
steel cam.......................-$320
billet alum. rods.............-$260
je pistons.......................-$280
racing valves(set of 4).....-$96
pro stock spring kit..........-$35
kohler lakota super carb-$250
steel flywheel.................-$150
billet alum. heads...........-$470

and a bunch of other stuff i cant afford.

By shane forsythe (Shanefor1) on Unrecorded Date: Edit

terry,
as i said in other topic post, good idea fixing clutch, no point having a powerfull engine if you can't put the power to the ground.

also the parts above sound good , but you will have lower fuel econamy if you put a stroked engine = more cubick inches = more power.

we have a saying in aust, it's a bit dirty:
if you want more inches stroke it!!!
lol.
shane

By terry harrison (Th3) on Unrecorded Date: Edit

attex bob,
im located in arkansas, southwest arkansas to be exact. how do i figure which jet is right for my area?

By Fred Sowerwine, Montana's Max dealer (Fred4dot) on Unrecorded Date: Edit

Terry, Why don't you look into the dial-a-jet from Thunder products

By terry harrison (Th3) on Unrecorded Date: Edit

fred,
i gave it a quick look and didnt see anything for the engine in my max. looks like a good product but no aplication for the command twin. ill give them a call during hours. thanks for the link.

By Fred Sowerwine, Montana's Max dealer (Fred4dot) on Unrecorded Date: Edit

Terry, Click on Motorcycles, etc.. then click on universal. I think the DJ-113 is what we need on all max engines.

By hellon6wheels on Unrecorded Date: Edit

terry i made my own jack shafts and went up 5 or 6 teeth on the big sproket and went with the stock #60 on the main drive sproket you might want to go to a thicker wall because where the busshing is fited there is not mutch meat left after the busshing is machined in place and the sproket is welded and depending how long of a busshing you use this could give you a weak point i have broke the shaft in this area before and you will lose total control of that side no steering or brakes and some pertty big eyes so if you go this route make sure you leave plenty of meat on the inside of your sproket and about 3/4 of a in inside of sproket from your weld thats my fix for more low end with a stocker but u will lose bout 5mph if thats ok with ya and cheeper than a biger engine i built mine for around a $100 and mutch stronger than stock jack shaft

By terry harrison (Th3) on Unrecorded Date: Edit

hellon6wheels,
what kind of 6 wheeler did you put the jackshaft in and can i see some pics of the jackshaft?

By terry harrison (Th3) on Unrecorded Date: Edit

thanks fred. i am going to check into it. it looks like a worth while installation.