2006 Argo Avenger with T20

[lewis]

Yes, that is quiet an attractive machine you have there!

[Mike]

It only took me 5 1/2 months but it is finally ready to be tested out. Mud flaps were the final task on my to-do list and I finished those up earlier this week. A lack of free time really drug this build out but at least it will be ready for Busco in a few weeks.

Here it is from two weeks ago when Jennifer first got to drive it:


Here it is with the mud flaps on it:


While I had it apart, I was debating on whether or not to throw a T20 in it but I knew if I did that, that it wouldn't be ready in time for Busco. racerone3 let me borrow his spare though so I could test whether or not it was even feasible while I had everything torn apart. You can read my thoughts in the gallery under these photos:

[foxvalley]

Congrats Mike! Looks like one sweet ride.

[rickga]

Nice machine mike! Like the tires too. Taking it to Busco?

[Mike]

Taking it to Busco?

Yeah, my wife will be driving it there.

[MikeyM]

WOW! That thing looks tough!!!! Good job! One of these years I need to take on the drive and get out to busco, from the videos ive seen, it looks like an awesome time!

[Rock Doctor]

Speechless

Love it

RD

[Mike]

I thought I would revive this thread and document the next stage of the build. It's been over a year since I initially purchased the Avenger. It took me several months to get it ready for a ride at Busco Beach last April and in doing so, I choose to keep the stock engine and transmission to save time on the build. On its shakedown run in March or April before the Busco ride that I was rushing to get ready, several things went wrong. While on the trails, the spring clip that holds the high gear on the transmission input shaft slid out of its groove and allowed some teeth to get eaten up. Then while limping back to the trailer, one of the brakes quit working and without steering, I was unable to stop from plowing into a tree. I didn't have enough time to get it fixed before the Busco Beach ride so I just parked it and didn't touch it for another several months as my work schedule got busy again.

Now I finally have some free time to start working on it again and I decided to upgrade the motor and hopefully put a T20 in it. I'm in no hurry this time and plan to take the build slow but I would like to finish it in time for next April's Busco Beach ride. If not, it's no big deal but that's the goal for now. So here are the things on the to-do list:

- Build a motor and transmission mount. I am going to copy the stock Avenger powerpack mount as closely as I can so that I can use the existing bolts and frame holes to hopefully save some work. This will also save me from having to build any chain tensioners for the T20 as the chains will be tightened by raising the entire T20 just like you do on the stock Avenger transmission. I have the mount design close to completion. I have designed it in CAD and printed off paper templates. Then I revise and repeat. I wanted to have the T20 output shafts directly over the intermediate shafts in the Avenger but in order to get the T20 all the way behind the stock firewall I will have to have it about 3/4" in front of the intermediate shafts. That should still allow proper chain adjustment.

- Decide on a motor. I'm leaning towards another Bandolero motor but have concerns since it's air cooled and I will have to build some ducting on the intake and exhaust. If I go with a motor other than that, I will need something with similar or greater torque and high RPM to make up for the single speed transmission. I'm not against building up the water cooled Kohler that came with the Avenger but I think having to relocate it will require me to relocate the radiator as well and then I would have to add an electric fan, better charging system, etc. I'm going to wait until I get the T20 located to see how much room I have and decide from there.

- Decide on the gearing. I have loved the gearing on my mid-engine Max IV so I am going to target that same gear ratio for the Avenger. It matches very well with the Bandolero motor torque curve and should have plenty of low end torque.

- Extend the splines on the intermediate shafts. The T20 is wider than the Avenger transmission so I will be extending the splines on the intermediate shafts to allow me to move those gears further outboard.

- Remove the Avenger steering. I initially wanted to keep the handlebar steering and make it work with the T20 but I have concerns of not having the T20 fully engaged while in forward.

- Build laterals and linkage. I have worked on the motor mount enough that I think I have the room I need under it to run the shifting rods. I have kept the T20 as low as I possibly can and plan on either extending the c-channels on the T20 down to meet up with the shift linkage or building some bends into the shift linkage itself. I haven't gotten that far yet and want to get the motor mount built first.

- Build the F-N-R shifter and linkage. I'm undecided on how I want to approach this. The T20 is right in front of the firewall so I could do something as simple as two handles sticking out of the firewall that you push forward or pull backwards. But I will probably end up with something a little more rigid. I am leaning towards a split shifter but have concerns about the torque on the T20 with a counter-rotating 8 wheeler.

- Modify the firewall and floorboard or build new ones. The plastic firewall will not work with the T20 as the recessed foot rests stick into the engine compartment too far. They will hit the secondary CVT. So I will either have to remold it with the heat gun or just build on out of aluminum. The floorboard will not work either as it sits all the way on the bottom of the frame plate where the laterals will have to be mounted. I'm not even worried about these until I get it running.

That's enough of a memory dump for now. I will try to keep this thread updated from here on out as I go so it's not so much information at once. I have some photos I can share later as well.

[mightymaxIV]

Wow, man you have a lot of work in front of you. I would leave the split shifter option alone. It takes to much power on a 6x6 and I believe it would over load the T-20 on an 8x8 with ASX tires.

I would consider a built 23 horse briggs, but as you stated cooling will be an issue, if you can get it to fit the fuel injected Kohler is a very nice engine. If you decide to go for a for a briggs it be intersting to see a hot rod 8x8 Argo with a 5 or six thousand RPM red line. I would like to see the look of the 4x4's when they see and hear that Argo coming a half a mile away.

It will be worth a trip to Busco just to see that machine eat mud!

[MAX IV Mark]

Just to share my thoughts (right or wrong as they may be)

I have the opposite opinion on the split shift, I think it would be benificial. On my bobcat skid loader you can hear the motor load on turning, being constant throttle hydrostatic machine. If you try to keep one side of wheels stopped and try to turn with only the other side moving, it takes a lot of power as it tries to drag those two stationary tires sideways(yes, only 4 wheels on it). But, If you turn one side forward and the otherside backward, the motor does not have to work as hard to turn the machine. This is somewhat similar (but not exact) to the concept of sliding friction versus static friction.

And since you want to keep the T-20 as low as possible, what is keeping you from flipping the U channels over and running the steering linkage over the top of the transmission?

MAX IV Mark