Well I finally made a little time to look into further, and actually do Minehunters Tranny Trick. He made a "how to" list a while back, there seemed to be a few interested auto guys who sounded like they would be interested, but were a little timid about actually doing it. I have to tell you first hand now, that if I can do it, anybody can. For the most part, it really wasn't that difficult. The hardest part was rotating the spring from the square hole, up to the new hole that must be drilled. That took a bit of time, a bunch of blood and a ton of sweat. -I fumbled around like a jackass with it for a while, managing to stab myself with the screwdriver a few times, which wasn't too cool, but I did get it to work. Here is basically what you'll need to do:
1. remove floorboard (13mm?)
2. remove footbrake by first pulling cotter pin and small plug thing, then remove the brake lever itself (17mm wrench and socket)
3. remove tranny vent covering with first section of breather (13mm, phillips head screwdriver)
4. remove tranny housing itself (11mm)
5. remove drive pulley -the one in front, which comes apart in a "half" section, leaving the inside half on the machine-(part towards the engine) with a 1 1/4" impact wrench
6. remove driven pulley with belt-keep in mind which direction belt is going (again, same 1 1/4" impact wrench)
7. flip entire driven pulley over to see round retaining plate with two round holes at the 12 o'clock and 6 o'clock positions, with a square hole at the 3 o'clock position. Square hole will have the spring end sticking up through-this is what you'll need to pop out and move after drilling the new hole.
8. carefully measure roughly 3/4" from center of the 12 o'clock hole, back towards the square hole, keeping it about the same distance from the outter edge of the retaining clip. Mark this location with the usual "X" roughly 3/4" from the center of the top hole, and roughly 1/4" I think, from the outter edge-maybe slightly more.
9. carefully drill small pilot hole, then re-drill with a 3/8" bit
10. This is the hard part-using screwdriver, pop the spring down into the retaining clip, then pry it to the outter edge, so it's actually outside the retainer itself.
11. Using vice-grips and combination of screwdriver, pull the spring up towards the new hole, then use the screwdriver to "work" the spring back into the retaining plate, and up into the new hole at approximately the 1 o'clock position. Again, this is easier said than done-this is the hardest part of the entire job.
12. with spring in new hole, re-install driven pulley back onto shaft. I packed the inside of the shaft housing with some marine grease just for good measure-might be something to consider for those that try themselves.
13. install belt, making sure of the proper direction, and making sure belt is flush with edge of driven pulley-i.e. so it's far enough inside the pulley itself, not to be protruding out of the pulley, possibly catching on the housing.
14. re-install main drive pulley, tighten with 1 1/4" impact wrench again.
15. Install housing cover.
16. Install breather cover.
17. Install foot brake.
18. Install floorboard.

That's it, you're done!

Upon testing out in the street, I found that in high range, the 'Cat really gets up and going much faster than it did before. In low range, the back end squats, front tries to come up a bit, she really gets moving quickly. I've got a lot of weight up front, so it won't have near the effect on my 'Cat that it would on an otherwise stock machine. It really does get up and go compared to what it did before-kind of throws you back a bit. I pulled up to the sidewalk curb, with the tires square against it in high range. Normally, I'd have to give it a little gas, the engine would rev a bit, then it would jump up over. Now, just a slight touch of the throttle and she jumps right up almost like you're in low range. In low range, it jumped up faster than I could hit the brake-again, with tires "square" with the curb to provide the most resistance.

I can't compare to a modified machine with say a K&N, jet kit or pipe, but I will say that comparing to my Dad's stock 'Cat-this simple mod definately gave me any lost power that I may have had from installing the huge 27" 'Claws, and then some. Even with the 'Claws, it gets up and goes quicker than my Dad's completely stock 'Cat-again, keep in mind all the weight I'm carrying around at all times. To a lighter machine with no weight up front or on back, I'm sure it would be even better results. To the auto guys running larger tires, this definately gives whatever power may have been lost from the tire swap back to you-easily.

I'm leaving friday for a long weekend up in the mountains to ride, where I'll really put the 'Cat to good use, and try to tow some logs as well. This will be with my sister and some of her friends again up near the Mt. Rainier area, and not on my own land, so I won't be in the real "working" conditions that I usually run. We'll need firewood for sure though, so I'll at least get to tow a few logs, this new trick should make that a lot easier for the 'Cat to handle. The trails are similar to what's near my elk camp-long, deep mud, lots of steep uphill sections, tons of rocks, deep ruts-basically a real good suspension test and a definate need for power. I'll give it a good workout, then post back here with the results either sunday or monday for sure.

I don't exactly understand how this works, as I thought it was supposed to put the machine into the proper rpm range for optimum torque and horsepower, yet where I thought it would rev higher, it doesn't. It seems to be running right at what it did before, only with a buttload more power. Whether I understand how it works or not is beyond the point-plain fact is, there is a very noticeable increase in performance. If anybody has any questions, feel free to ask, I'd be glad to try and help. Again, I'll post back here after the weekend is over with full report of how it operates in the field. The best part is this costs absolutely nothing, other than a couple hours of your time.

From what I've seen thus far, I definately give "Minehunters Tranny Trick" two thumbs up!

Best of Luck guys, and Very Special Thanks to Minehunter for all the help! I've been bugging him a lot lately, I greatly appreciate everything he's done-hopefully this will help somebody else who's thinking of doing the same thing.

Ride hard, Ride safe,

Mike

 

[img]i/expressions/face-icon-small-smile.gif[/img][img]i/expressions/face-icon-small-happy.gif[/img] Thanks Mike for the kind words. I just hope that this works out for you as well as it has for me. One thing I did notice was a slight decrease in my mileage range. Not much, but some.

Now come Monday I hope you feel the same way. Now go out and have some fun. After all it sounds like you did to get this done you deserve it.
[img]i/expressions/face-icon-small-smile.gif[/img]

 

Did this mod help to increase your top speed at all?

On another note, did either of you adjust the carb or valves after the first year?

 

First off- GSPman-This mod will not increase your top speed-it works on LOW end only. In fact, if you move the newly drilled hole TOO high up towards the 12 o'clock position, you'll loose quite a bit of top speed in replacement of a HUGE low end gain. Installing the spring at the 12 o'clock hole will result in the biggest low end gain, but will also loose about 12-15 mph top speed. Drilling at the 1 o'clock position gives the best of both worlds-a great low end gain, with very little to no loss in top speed. As for the carb, yes, I pulled the stock 150 jet and replaced with a 145 for my riding altitude. The 150 was too rich, it was forcing the carb to take more fuel than it needed, not burning it all, causing slightly poor performance compared to the leaner jet, and worse gas mileage. When changing to the 145 jet, I got better mileage, and better performance-it is now using all the fuel it takes, rather than being "force fed". For the valves-no, never touched them. Dealer said he has no reason to believe they need adjustment, so I've left it at that.


Now, got back from the weekend trip a while ago. Due to some unforseen circumstances with my boy getting sick, going to the hospital, my trip was delayed a day till I knew he was fine and I could safely leave town without worry. Yes, he is fine now, just a STUPID mistake by the hospital. At any rate, was only able to put on about 20 miles with the new mod, but I did get a great feel for how it works, and I LIKE IT!

The first thing we found was a mudhole about floorboard deep -this was all the mud we found, so that's what I had to play with for starters, nothing deeper. I've never really been able to really spin the 'Claws good in high range before in mud, could barely get them going in low range. Now, in high range, they'll roost pretty good, really flinging stuff everywhere. I left it in two wheel drive, as in four wheel, I was getting bombarded with mudballs, and for those that run the 'Claws, you know full well those "mud *****" are HUGE! The 'Claws really kick out the crap. Anyway, in the mud, it's a great improvement in both high and low range-low wasn't even funny, it just spun like crazy if I wanted it too.

For hills, I found a few hills that I had to run in low range before, that I can now take in high range with ease, and not worry about burning the belt. Setting the spring like this puts it in the proper rpm range for optimum power/torque, so it made it climb better in high range. Again, low range wasn't even funny. It almost made low range "too low" for some hills, as what I would normally switch to low to climb, I can now use high range, switching to low just took too damn long to climb up. For the REALLY steep stuff, low range is always necessary, just like towing things. In this type of terrain, this mod really shines. For the really steep, nasty rutted, slippery muddy slopes, with tree roots, rocks, boulders, etc., with very little throttle low range has the power to just basically crawl right up this crap with hardly any effort at all. Where before, I'd really have to be on the gas to make it up, now she gets up much easier, and with less throttle-a huge improvement.

Towing logs-I didn't get to tow very many logs, but those that I did tow went surprisingly easy! I might get myself in trouble with this now, as I'll have to remember since it tows them easier, I SHOULDN'T try towing huge stuff now just because it can-it will make towing the stuff I normally tow a lot easier for the machine, that was my goal. Even though I am now able to tow much larger stuff with relative ease, I'll have to keep in mind that this is still an auto, and I don't want to get too crazy towing things that a tractor or diesel pickup should really be used for. Overall, it did awesome for the large logs I did pull, which yes, they were larger than what I normally pull around at my place.

In high range, it gets up and goes quicker than it ever has. Before, from standstill side by side, my Dad's stock 'Cat could get the jump and start to walk away from my 'Cat with the 'Claws. This is no longer possible. I keep right there with, or pass. On an uphill grade-I've got it every time, as the power is right there when you touch the gas, as opposed to his needing to reach the proper level to hit maximum power before it will really go. If this sounds like racing to you, don't be fooled. Having this power available that quick for the machine to the wheels translates to far superior mud riding capabilities, as you can get a higher wheel speed sooner to better clean out your tires in really thick gumbo mud, allowing you to get through deeper holes better. For me, I'm able to tow those logs a lot easier now with the power avaible "right now", as opposed to it taking off, then slowly getting to speed. Kind of like a "granny gear" in trucks.

In the real suspension flex stuff, like the "belgian road test" type stuff, with full articulation and suspension work out's, this new tranny trick is great. You have the feeling of better control of the machine while crawling up and into a lot of the terrain where you'll have only 3 wheels on the ground, sometimes only 2 at times. Drop it in low range, just barely touch the gas, she'll easily climb in and out of this stuff all day long. While I only hit 20 miles, most of the day was in this type of terrain. I switched with my buddy half way through to see what he thought after riding both 'Cats, he felt my machine was the better ride-that he had "more control" in those types of situations. The engine doesn't need to rev as high to get you over the fallen trees, you don't give it as much gas to get moving from takeoff, it pulls you up and over sooner, easier. Hard to explain, but after riding both machines with and without the mod, there is a clear difference.

The ONLY drawback I see is that because the engine is operating at optimum rpm range, you will use slightly more fuel. When I changed jets, I gained a little more in mpg due to the leaner setting. With the tranny mod, it took a little of that gain away, but not all of it. I still get better mileage than my Dad's 'Cat, but not by as much as I did before the tranny job. I never changed the jetting in his 'Cat, it is still stock. So, on a stock jet, you will probably loose a tiny bit of fuel mileage. I don't think it's enough to really notice or worry about, but felt it was worth mentioning in the "whole skeem of things". For the power you gain, this tiny bit of fuel drop isn't even worth bothering about. I probably shouldn't have mentioned it, but at the same time was trying to cover everything about the tranny trick-good and bad. I don't even consider this to be bad, as the power gain is that good. Unless you really watch your fuel very closely, I doubt you'll even notice the difference.

My overall consensus is "Minehunters Tranny Trick" is definately worth doing for anybody running an auto 'Cat with larger than stock tires. I've gained back any power that was lost from the larger tires, and then some. It is greatly improved in all aspects of riding and towing abilities for my riding and working styles. I believe anybody else running the same types of terrains or doing the same types of things will greatly benefit from the job. On a stock 'Cat with stock tires, I think it would be even more noticeable, as you don't already have the larger tires to compensate for-but I could be wrong on that one. I plan on doing this mod to my Dad's stock 'Cat when I have time.

Anyway, hope that helps or at least answers any questions that may have arisen. If there's anything else, just give me a hollar.
And once again, THANK YOU MINEHUNTER-GREAT TIP!

Best of Luck,

Mike