By IG-88 on Unrecorded Date: Edit

I have lowered my ratio to that of a max IV.
A max II has a 1.8 to 1 from the trans output to the wheels, trans 15 tooth, j-shaft 27 tooth and a 1 to 1 from the j-shaft to the center axle.
the MAX IV has a 15 tooth trans, & a 34 tooth drive, that gives a 2.27 to 1. I gave my MAX II a 2.223 to 1, about the same. Pulling and low end grunt is great, a big improvement, turning is really easy to. I had the 21 tooth sprockets cut off and 17 tooth sprockets welded in there place from the 1 to 1 side of the j-shafts, so now it's a 1.235 to 1 x 1.8 to 1 gives the 2.223 to 1. I have all the pics if anybody wants to see, e-mail me.
Later

By ISAAC EISENMAN (Tropicjungleboy) on Unrecorded Date: Edit

HEY IG-88: nice increasing torque job!!! now your belt will last longer!!..but i think that the reduction factor values that you mention on the maxII are wrong....jack shaft have two sprockers...one ansi 50 ( t-20 to jack shaft) and one ansi 60 ( jack shaft to center axle)...on the center axle you will find a 17 TOOTH ANSI 60 sprocker on center and two ansi 50-21 tooth or on older models ansi 40-26 tooth..one inner/to drive front axle and one outside/to drive rear axle.. ansi 40-26**ansi 50-21**ansi 60-17 has same diameter...therefore your original reduction ratio from t-20 to axle goes as follow:

27/15torque inn.......1.8 reduction on jack shaft
17/21torque inn.......0.81 reduction on axle (o.d)
0.81/1.8..............1.46 standard final ratio

now..with your improvement you have

27/15torque inn.......1.8
17/17torque inn.......1.0
1.8/1.0...............1.8 your actual final ratio

by the way you have now 24% more torque and 24% less top speed..

By John Martin on Unrecorded Date: Edit

Ig-88 that Max II sounds like a great hill climber! What size engine do you have in your Max II? What made you want to put in the lower gears? I think that is a good idea to provide great power(torque) without having to modify the engine.

By IG-88 on Unrecorded Date: Edit

Isaac,
my max is a new 2001 unit, it has 530 & 520 "O" ring chains, non of the older 60 type chains. My gearing is correct, my j-shaft "had" a 21 tooth on one side and a 27 on the other. My drive sprocket on the center axle has a 21 tooth also, so that makes it a 1 to 1 from the factory. I changed the 21 tooth on the j-shaft to a 17 and rest is just like I said before. I really don't know the gearing on the older ones, but I do know that my gearing is a 2.223 to 1, and not 1.8 to 1 if you call RI they can help, or I can send you some pictures of mine. One more thing, if anybody needs two 21 tooth sprockets, these have about 4 hours on them, let me know. They only take the 530 or #50 chain.
Have a good one!

By IG-88 on Unrecorded Date: Edit

John, my max has a 16hp B&S vanguard. What made me do the mod. was that a bigger engine would cost $1100.00+ and what I did cost $212.26 total.
I put less stress on the trans & engine and the turning is allot more responsive & sensitive, I thing this modification would help all maxII owners if they had a 14hp or up to a 20hp engine and if top speed isn't a prime factor. Remember, a good machine shop is worth it's weight in gold when doing this. And I also wanted to say that it is not necessary to shorten the drive chain for this mod.

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

IG-88, Every one is entitled to do what they want with their machines, but it takes about 25 hours to break in any max (for the tranny bands to find their groove and for the springs to loosen up). Even the 14 hp max has plenty of low end torque (once broken in) to climb the steepest stuff. The stock machines are perfectly well designed.

In my opinion, no one should consider any modifications until the machine is broken in and the driver knows how to operate it.

By John Martin on Unrecorded Date: Edit

Fred, I might agree with you that a person might want to wait until the machine is broken in, but I always think about more torque and power when I'm stuck in the mud or pulling long steep hills. I think ANY modification that can be done to increase torque or power is worth the investagation to see if it will benefit your machine. I know not everyone needs lower grears to do what they are doing with the Max. I don't no about you but I'm like Brandon, and aways want more torque and power. I think the Maxes are great, but like anything else you can always improve something to make it work better for yourself.

By IG-88 on Unrecorded Date: Edit

Fred, I have drove older (76 & 88) maxII's & a 2000 model maxIV, I liked the low end power of the maxIV but the looks of a maxII, so I bought a new maxII and changed it to fit me. It would have made no differents if it had 2 or 250 hours, I would have changed the gearing anyway because I like to be different. Some people like to go with the flow, I make my own river. In my opinion that is what the USA is all about, and why it's the best, freedom to do what we want!

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

John, I have no problem with people changing things to suit themselves, but most people want more speed thinking more power (hp) will give them that. All modern Max have torque enough to about idle up the steepest of hills carrying a full load (and to be able to stop mid hill and restart). The problem for many people is, they don't go much faster at full throttle if the hill is steep enough. What they need is not more torque, but higher RPM or a lot more HP.

IG-88, In addition to the above. The '76 would have been a two stroke and would have been pretty low on the torque scale (if you wanted to climb a hill with them, you had to go at it about full bore); the '88 could have also been a two stroke or would have been the Tecumseh (their 16hp engine puts out about the same hp as the 12 1/2 hp vanguard did). Again, I have no problem with you changing your machine to suit you, but your suggestion that all Max II owners should consider doing what you did is not in their best interests. I just don't think lower gears are a plus in any max and it will hinder resale, for you and anyone else who does it. That is my OPINION and I certainly agree with you wanting to make your own river.

By MaxRules (Brandon_price) on Unrecorded Date: Edit

Changing the gearing is not a bad idea, but you should change the engine if you really want some improvement. Lower gearing would be great for power but I need more speed also.
I did my engine mods mostly for hill climbing speed and wheel spin in the mud. The 14hp will climb any hill but it is entirely too slow for me. Also, some hills with loose terrain require more speed.
My Max can now climb steep hills without losing all the speed and the engine doesn't bog. My modified 14hp can probably pull hills faster and easier than a stock 16hp with lower gears. Mine also runs a lot faster on top end. Still not fast enough though, I think I need some clutch changes.

MaxRules

By neil otto on Unrecorded Date: Edit

Lower gears for Max IV? I put Tru-trax on my 91 Max IV with Kohler 20 hp and found that I run out of power long before I run out of traction. The Max IV has no jack shaft. Has anybody successfully lowered the gear ratio on this machine, and if so how? Thanks, Neil

By Joe on Unrecorded Date: Edit

I hope someone can help me out with this, I want to change the gearing in my Superchief from 1.63 to either 1.38 or 1.25. The problem is I don't have any comprehension of how big these changes will be. the machine has tuned E.C.'s with plenty of bottom end and mid range but lacks on the top end. Top speed now is about 40 mph + or -, How big of a change in top speed will either of these gearing changes make. Any input would be welcomed.

By david berger (Davidrrrd) on Unrecorded Date: Edit

JOE,
WHAT SIZE TIRES ARE YOU USING?
SWITCHING TO 22"TIRES FOER A WHILE MAY GIVE YOU AN IDEA OF WHAT YOU CAN EXPECT FROM A FINAL DRIVE RATIO CHAINGE, DIFERENT MAKES N MODLES HAVE DIFERENT CERCOMFRENSES AND YOU NEED TO FIND THE BIGGEST THAT WILL FIT FOR THE EXPIREMENT.

By Truro on Unrecorded Date: Edit

I had my Argo clucthes apart and made some adjustments. With the low ratio trans, it had excess low end and limited top end.

I noticed the belt didn't climb all the way to the outer edge of the pulley on the engine clutch, so I added a shim to make it so. That added several MPH on top end.

The trans clutch has a spring that can be indexed in different holes affecting tension. That affects the rate at which the transmission gears up and down. The clutch is torque sensing, it stays in lower gear under load/hill, etc, then shifts higher as load decreases.

Now it drives much nicer, gets up to speed faster in less time with less RPM. Also has a faster top speed.

By Joe on Unrecorded Date: Edit

I am running 22 in. tires @ 5 psi, the torque converter and driven variable pulley are both brand new and work properly. My goal is to keep the engine rpm to where it runs best, bottom end and mid range by gearing the axel drive ratios up.
I just not sure of how far to go with the gear ratio.

By david berger (Davidrrrd) on Unrecorded Date: Edit

JOE I HOPE THE MATHAMETITIONS HERE CAN FIGURE OUT WHAT NUMBER OF TEATH SPROKETS YOU SHOULD TRY BUT MYSELF I CAN ONLY CONTRIBUTE THIS ADVICE:
WHEN YOUR DONE WITH YOUR MODS AND ABLE TO GO FASTER REMEMBER TOO AIR DOWN AS MUCH AS POSABLE.
THE LOWER THE BETTER, RIDE WISE BUT ONLY TO THE POINT WERE YOU MIGHT DAMMAGE THE TIRES OR RIMMS, NO LOWWER,
5 PSI IS TOO HIGH AT SPEED!

By liflod (Liflod) on Unrecorded Date: Edit

Sounds pretty odd that your 2-stroke runs better at low and mid RPM instead of high RPM. My 440 will go 45 MPH and the engine is only at 5000 RPM. The 2 stroke should rev to 7000. I would try getting the engine running better at high rpm before putting too much time ,money and effort into the gearing. How fast do you really want to go? If you change the gearing, you will definately hurt your low end (slow speed ) power.

By Joe on Unrecorded Date: Edit

Would'nt you say that 5000 rpm is mid range for a two stroke? The engine runs fine, the machine is gear bound!! I am turning about 7200 rpm to go 40 mph it is not a question of how fast I want to go, I want to gear the machine so the engine stays in the rpm range that it runs best , which is between 3200 and 6500 rpm. If I gear the machine up it will give me a broader power range than I have now(too much bottom end). I dont want to go too far on the gearing and loose the all the low end. That is why I posted the original question. Shouldn't your two stroke turn more 7000? sounds low to me.As far as getting the engine to run better, I don't think it can run any better! I've bored it out, new crank, new carb, tuned dual EC, it red lines at over 9000 rpm. But if you can think of anything I'll try it.

By Marc Stobinski (Jerseybigfoot) on Unrecorded Date: Edit

Joe. There is no clear cut answer to your gearing, If your engine overrevs on acceleration you may also need a converter change along with a gear change. in what distance does it get up to 40 mph? 50' or 200'If its 50 or less you can afford to take some teeth off the jack shaft gear. 2 stroke power bands are all different. Piston ported engines have narrow bands. For the older 2 stroke piston ported engines you have less than half the hp at half useable rev range. 20 hp @ 5500 rpm = 8 hp @ 2500 rpm. On my 440LC Scrambler I have quick change split sprockets on the jackshaft like a go kart. Maybe you can do the same for your max.

By david berger (Davidrrrd) on Unrecorded Date: Edit

JOE SOMBODY NEEDS TOO MENTION MARKS SCRAMBLER HAS BIN CLOCKED IN A SMALL FEALD(A LITTLE OVER 1 AKER)
AT SPEEDS APROX 68MPH OR SO, ALL THIS AND YOU HAVE TO SHUT DOWN AND ROLL ITALMOST AS FAR AS IT TOOK GAIN THAT SPEED BEFORE IT'S SAFE TO USE THE BRAKES OR TURN , SO WHAT MIGHT IT DO IN THE OPEN?
SEE IT FOR YOURSELF ON THE 2002 PETES SPRING FLING VIDEO