25" Rawhides on a 1999 Conquest?

[Pophamrt1]

Looks like someone already did it, reasonable or not. The owner of the '99 Conquest on Ebay returned my email: The 25" Rawhides are legitimate. His brother was/is an argo dealer and either ordered or extended the wheelbase.

I went back go the picture and its clear that they're 25"... the tire top to tub gap is too tight to be 24." Say that quickly twice. The 1" or greater gap between the wheels suggests a 5" extended wheelbase, the maximum the tub would allow.

25s on Conquest.jpg

I guess the outstanding question is has anyone done any significant alterations or repairs to Argo tubs? How did they hold up? And, what equipment did you use--hot air with injection tip or just hot air and stick methods?

I guess "reasonableness" is individual. But technical issues can be limiting, and thankfully you guys are very knowledgeable. The chain point, frontier tire points of reference and other input is appreciated. I typically enjoy engineering and designing in CAD, watching chunks of metal transformed to 3D, tearing down and fabricating, testing the parts and improving them. Keeps me out of trouble. If I had an Avenger I'd be trying to put 28s and active supsension on it.

[Roger S]

You are right, if you compare the rear axle center to the 'Conquest8x8' badge on the body, it's several inches different than a stock response/conquest .

Only other thought is I would be inclined to tighten the axle centers at least .010", my chains were a little sloppy even on the new machine. A chain in the rear is 5ft, and an 1/8" stretch makes for a lot of slop.. Also keep in mind the frontier/avenger bearing extensions which are square.. if you can't flip yours around.

[Bw6]

Another Option

Here is another option to muddy the water even more. A couple of years ago I had a change to get a low hour Argo Magnum (forerunner to the Conquest) pretty cheap. There were a lot of things I didn't like about it, especially the 24" centers. I went through all the options like you are doing and decided if I bought it, I would purchase an Avenger lower body from Argo, strip down the Magnum, modify/beef up the frame to match the Avenger wheel base, install Avenger bearing extensions, reuse all the other parts or upgrade to some of the Avenger parts (tensioners etc).

The Avenger lower body is 119" lg. same as Conquest, there was about 2.5" difference in the width (1.25" per side), so I was going to make up a angle filler to match the profile. This I felt was the most practical way for me to do it. I also thought about buying the Avenger upper body, but they were a bit pricey.

Off topic: So what did I do? I bought a Bigfoot (excellent machine), stripped it down to the bare tub and did a few mods. Even though it had RH III's (hate them), I wanted more tire out front, to assist traction in climb outs, and looked at Avenger bearing extensions or flip the Bigfoot ones around, but decided to leave it alone. Here are a few pics, the frame is similar to your Conquest:

[Roger S]

Ray, your pics reminded me that the bigfoot doesn't have the tube frame in the rear. I started lookng at vanguard pdf's over the years.. pre 95's had channel front and rear, the front axles moved forward in the frame, the rear not as far as the frame allowed. In 95 they went to a tube in the front, in 97 they pushed the rear axle to the back like yours, same time as the bigfoot came out. (same frame) The response and conquest always had frame tubes front and rear. I guess 95 was their first year hence the vanguard front tube. Those tubes are in the way of sprocket spacing, but are hell for stout, allow frame flex. I've never seen a crack anywhere in my frame.

you guys can correct me if my hasty reading is wrong..

[Bw6]

I Agree

Yes Roger, I believe your right. I think the idea of the frame tubes front and back was to allow for an option of putting rear bearing extensions, but not sure. I think Pophmart1's idea to leave the front alone is a good one. That gap between the frame and the hitch is a good place to gain wheelbase, and then adjust the axles centers to suit the actual space gained. It's too bad that Argo didn't design their frames to allow the front tires to stick out further ahead of the tub, the Mudd-Ox front frame is similar to Argo's as well.

Roger with your technique of jumping in the rear, thus transferring your weight rearwards, and allowing the front to lift up, and then moving to the front, when the climb begins, makes up for moving the front axles forward, but not everyone is agile as you, LOL. In BWII I maximized the forward placement of the axle by designing my own bearing extensions, which so far are doing the job.

I hope Pop, goes ahead with this mod. and documents the process, it is long overdue.

[Pophamrt1]

I'd agree too, the front "should" be left alone. But I just ran the spacing numbers and based on 5/8" chain increments, the only way to get enough room for a 26" tire on a K-Loc 10" rim would be from the added benefit of first moving the front forward by one increment/chain link (0.6250"). While a PITA, doing so would allow OD tires of 25-1/2" (ASXs, Swam Fox Plus, etc at 4PSI) with 3/8" tub clearance before any heating/modiification. You guys have had serious argo seat time in varied conditions. Any thoughts on raising the front axle height by about 1/2"? Thought would be to raise the fronts position by about 1/2" to gain part of the realestate required, paricularly if there's a benefit to assist in climbing. While moving them back, also move the two middles down 1/4" and bring the rear up 1/4" (or leave it alone to optimize traction). The combination would mimic the Avenger pivot layout.

Interenstingly, when you use the chain increments to re-space the axles, and start by moving the front forward by one increment, the last axle (No. 4) drops dead nuts into the current position of the exsting rear crosstube. The new No. 1 and No. 4 axle positions also align with the radius of the rounded tub fenders that drop at the front and rear. No way that's a coincidence; looks like the outer boundries of the tub's design points.

Roger, did you mean 0.01" or 0.1" for a chain adjustment factor? If you meant per link, 0.01" would be just shy of an inch over 5 ft. Otherwise, the current chains on my Conquest are close to new and would take a nice 0.1" tightening.

[Roger S]

I meant ten thousandths tighter axle centers, don't take that too litterally. What I mean is none of my chains were that tight when new, and with a few thousandths wear here and there on sprockets, splines, etc, things are less than perfect for a system that really doesn't tolerate chain adjustment. I don't know what the actual exact axle spacing is, I'm just mentioning that I would be really critical on the specs if I was doing this. I would probably take new or very good sprockets, slide them up on unused spine area, with new chain I intended to use, stretch them in a jig and get a precise measurment on centers. You can figure it out.. you'd want to get your used stuff as tight as possible but still be able to get a chain around new parts if necessary down the road. I don't know when argo went to the ratcheting chain adgusters, might be an idea.

Moving the axle heights up and down.. have to think about that. I wouldn't have considered raising the front. The avenger has 1" drop on the 4 middle. Mine is a 1/2. Does steer easier but as mentioned the sprocket is in the dirt and the frame rail is thin at the bottom. As far as traction, climbing..don't think it helps, might hurt, depends on the piece of dirt you're on. seems to help ride quality a bit, sort of a rocking chair effect. The back tires are off the ground on flat hard surface with an empty vehicle, hence the eased steering.

[Roger S]

I might suggest lowering the 4 center axles a 1/4" leaving the ends where they are. You could raise the ends a 1/4" but that goes against ground and tub clearance. I don't think the Mudd Ox has differing axle heights and it rides and tractions/climbs well. I think it was bandaid fix for argo's power robbing differential tranny when the avenger was introduced with a 26 hp engine.

[Bw6]

I just did a layout to see if there was any other solution to using a max. 25.5" dia. tire but came to the same conclusion. You need to move the rear axle back 5" and the front axle ahead 5/8". Going from front to back you will have 44 pitches, 76p, 102p, 102p. This will give you 1/8" gap between tires if I'm correct. Also as you know moving that front axle ahead 5/8" is going to be a real PITA. Maybe settle on a 25" max. tire dia. selection and leave the front alone. Also as you know running larger dia. tires will most likely require HP or CVT changes as well.

[Pophamrt1]

Roger, I like the concept of tightening up the chains by tweaking axle locations but Argo’s manufacturing tolerances may be an issue. I’ll likely work off the existing locations by making new axle mounting plates that include an interference fit to those points. Picking up the existing data points means accepting Argo’s frame tolerances/accuracy. I’m guessing that Argo cuts the mount points into the stock, then welds together the frame using jigs. Depending on their jigging and welding techniques, the axles and mount points may have pretty rough tolerances center to center… they likely chose to go a bit closer center to center as its better to have someone complain about slack than not be able to get a new chain on. When I look at the chassis out of the tub I’ll have a better idea. But I’d like to be able to run plates for others so making fine adjustments based on the nuances of my machine may not be a common solution.

Regarding axle heights. Your suggestion of lowering the center axles by 0.25” seems perfect. With 25.5” tires and the mid axles moved down 0.25” it’s already gained 1” of tub ground clearance compared to 24” tires. If it rests on the mid tires and the front and rear are up 0.5” relative or a bit more, there would appear to be a bit of an advantage climbing. For example, a log the same diameter as the tire… there’d be upward tread leverage as opposed to forward pressure. Slight, and primary consideration is how to gain a bit of front tub clearance for the frame.

Bushwacker, with the changes, the gap between 25.5” tires works out to 3/8” (0.3750”). 1.8750” move (0.6250 x 3 pitches), added to 24.0” axle centers equals 25.8750”, leaving 0.3750” between each set of tires. Conceptually, splitting the gained 3/8” in half for each tire would seem appropriate, but when you draw it out in CAD its clearer. This assumes dead-nuts accurate existing center-center axles distances of 24.0” (not likely from previous posts by Roger and Rock Doctor), but 3/8” is enough room to work with if there needs to be some tweaking.

It’ll definitely need more power. The current FD620 is in good shape but I have a 27hp FD750 on the shelf. That and Roger’s guide to clutch setup should be a good starting point.

I can’t say that I’ll be tearing the Conquest down in the next week or even month, but I’ll start making some CAD designs for new mounting plates at night.

[Roger S]

Been meaning to ask if you're aware of the 1/8~1/4 inch closer spacing between the first and second axles.. due to the idler shafts in the mix. RD and I have to put the 4 shortest tires up there..

[Pophamrt1]

Thanks for reminding me. I wasn't factoring that idler in yet. Measures about an 1/8" on mine. Might have to bump No. 2 back by a single link (0.3125") and move 3 and 4 the same additional length. Getting tight in the rear tire to tub lips area and front tub to frame clearances. Moving that front forward is really a pain with the bearing extension tied to the cross-tube. Some thinking to do.

[Roger S]

We can't think in single links, 'cause it takes 2 sections, unless we use 1/2 links which I don't think are as strong by looking at them.. I have no experience with them, though.

What if you left the front frame tube where it is, and cut out and walled in a slot for the sprocket and chain to recess into? Then use avenger brg extensions.

[Pophamrt1]

Sorry, meant half link. I've never used one either so will have to do some digging. But as a principle, any change made have to be equal or stronger, not weaker.

If the 4" front frame tube was cut less than an inch and structurally boxed, there would need to be some additional bracing added to regain it integrity. Doable. PITA though. But, its the difference between fitting allowing 26s versus only 25. Seems like while you're in there...