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Discussion Starter · #1 ·
Hi,

I had a good afternoon ride today -- took both Tundras up high.
Both my Tundras are geared down to the max.

94 Tundra Modifications: 2 teeth smaller on top sprocket and 2 teeth larger on bottom sprocket. 130 main jet for high altitude. Plastic ski skins.

06 Tundra Modifications: 1 tooth larger on the bottom sprocket. 130 main jet for high altitude. The limiter strap has been loosened one notch.

First I want to say that the 2006 Tundra is a great machine -- better made than the 94 (I think). It handles so well and is very smooth -- a lot of fun to ride. My wife much prefers to ride the 06 and doesn't particulary like the 94. On a long rough trail I will also choose the 06.

However, today we got both machines up high where the snow was soft and I switched back and forth -- riding one and then the other in the same places. My conclusion was that the 94 wins hands down in soft snow -- kept going where the 06 would get buried -- stays on top better. I think the reason is that the 94 has a 139.5 inch track and the 06 has a 136 inch track. That little longer track plus less track used by the suspension keeps the back of the 94 on top in the soft snow. There is not just a little difference but a significant difference. I have always known that the 94 Tundra will out float any 136" track machine out there and was hopeful that the 2006 Tundra would also. It might (with the exception of an older Tundra), but I would be a bit more confident on the 94.

My conclusion is that the only way the 06 will be competitive with the older style Tundra in soft snow conditions is if it gets a longer track and lower gear ratio. A bigger motor will only hurt the flotation deficiency and dig a deeper hole. I'm still glad I bought it. The Freestyle and Tundra are both great choices for our lighter riders. My wife likes the the RF seating position and the fact that it turns easier. The 06 also does not have as much driveline noise making it more pleasant to ride. The 94 is not all that great to ride on long rough trails but it will be my choice is very soft snow situations. In a race -- well, the 2006 will certainly beat the 94 and I'm sure a Freestyle would beat either one on an obstacle course. Yep -- the 06 needs that 144" track to compete in the soft stuff.
 

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what would you think of a 144X16 track with a 300 twin in it. I think the single is a little lite on the power when getting into or out of the slush. Just a thought.
 

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Discussion Starter · #3 ·
walleyeguy said:
what would you think of a 144X16 track with a 300 twin in it. I think the single is a little lite on the power when getting into or out of the slush. Just a thought.
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Hi,

It looks like it might be possible to put a 144x16 on and not have to extend the hull at all. It seems like there is enough width and length. I emailed a place to see if their extension kits will work on the Tundra. Re the 300 twin, my experience has been that the same displacement twin will have less bottom end torque. And, it would add weight and complexity.

Since the 94 has plenty of low end and can easily turn the track when fully buried I just think it is a clutching/gearing problem on the 06. If I put a 144" x 16 track on the Tundra I would also reduce the drive sprocket by one tooth which would hopefully cure any power problems since that would be a significant reduction in gear ratio.

But hey, I hardly ever ride in slush around here
 

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I think the struts on the 94 help out when in the fluff??

What are your observation regarding that????
 

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Discussion Starter · #5 ·
FreezerBurnt said:
I think the struts on the 94 help out when in the fluff??

What are your observation regarding that????
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Hi,

You are correct that the fancy suspension looks like it would be a snowplow going into the deep and soft whereas the old style with the struts looks like it would have less drag. However, the skis on the 06 are 1" wider which seems to help that problem. The 94 goes into the soft snow fairly level whereas the 06 seems to go in "nose up" even with your weight forward. I have not been able to observe the 06 from the front with someone else riding it -- this is just what it feels like when I'm on it. If the front end is causing a lot of drag, then of course the rear would dig deeper. It sure will take a bump nicely on the plus side. If it is the front end is causing the problem then putting 144x16" track on it may not be the solution. But, it feels like the track is borderline on the flotation and simply falling through easier than the 94 due to the 2" less track on the ground or maybe even less since more track is sucked up in the suspension (I.E. the more travel you have, the less track you have on the ground). If more flotation in the rear is what it needs, than a 144x16 should make a very significant improvement. Hum -- I should measure the square inches of all of the front end drag on both machines for a comparison -- the "boat hull" looks like it would also have less drag than the more blocky aluminum hull once down that deep.
 

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You just arent going to beat the original Tundra for what it does. I was skeptical about the news one to begin with. Just the physical aspect of it. Aside from the new ones being horrifically ugly, I dont think they would stand up to even a minor case of tree magnetism. They just wont be able to be thrown around like the older ones...without doing a bunch of body damage.

What are the gears in the new Tundras? '94's were 14/25, prior to that was 12/27.
 

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Hey Dan, new to this forum (and ski-doo) I just picked up the last 06 tundra here in town (Fairbanks Alaska) Made a few mods and went into the mountains this weekend. I installed a ATACC (jettet with a 210 main) she burned perfect, checked the plug a few times and color was great.

I was out with guy's that all had big machines so I couldn't compare, but, I run with guy's that all have the older style tundras, you say the 94 has a 139" track, do all the tundras from 94 on have the same? (not including the 06)

I was hoping to show up the old sleds, but it sounds like your testing shows other wise. When you changed the gears on the 06, are you dropping the ratio so you have more low end? And when you do that, are you making any changes to the clutches so your rpm's stay up to 7,000 (or whatever the optimum is) ?
 

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Discussion Starter · #8 ·
Hi,

This reply is in response to several questions:

1. Struts vs A-arm suspension: The struts have a total drag area of 23 square inches. The A arms (only counting front side) plus tie rods, etc have a total drag area of 58 square inches. However, the 2006 tundra has 80 square inches more front end flotation due to the wider plastic skis.

2. The pre 2006 Tundra Long Tracks (LT) all had 139.5 inch tracks where as the 2006 has a 136" track (more standard length). The 139.5 inch track had its origin with the old double track alpines. The other factor to not forget is the longer travel the suspension, the less track on the ground.

3. The gearing comparison is somewhat complicated. The 2006 Tundra has a much stronger sprocket/chain setup than the old tundras -- completely different. The stock gears on my 94 were 14/25 and I changed those to 12/27. The stock gears on the 2006 tundra are 15/45 and I changed to 15/47. Since the 37 had to be ordered from Skidoo racing and only came in aluminum, it was very expensive as well as the cost of the new chain compared to my gear swap for the 94 (It took me about 30 minutes to swap out the sprocket/chain). However, the new chain/gear setup is strong enough for a much bigger motor. Now, the track drive sprockets are different diameters so how do you compare the overall gear ratios? This is how I did it.

The diameter of the sprocket of the 94 touching the inside of the track is 4.5" whereas the diameter of the 2006 sprocket touching the inside of the track is 7.5". These are rough as I did not take the sprockets off.
94 -- 27/12 = 2.25
06 -- 47/15 = 3.13

To equivalence the ratios -- the circumference of the 94 drive sprocket is approx 14" and of the 06 is aprox. 23". 14/23 = .61. So 3.13 x .61 = 1.9.

94 ratio = 2.25 and equivalent 2006 ratio = 1.9 given my rough measurements (reaching under the track). However, this feels about right riding them as the 94 will turn the track easier when buried.

4. So what does this all mean? To me it means that the stock older LT Tundra will out perform the 2006 Tundra in soft snow conditions primarily due to the larger track footprint. But, the 94 Tundra is not much fun to ride for a long distance (i.e. the trail getting to the soft snow) where as the 06 is loads of fun. Overall, the 06 is built to handle a much larger motor with the beefier chaincase. Many little improvements are evident such as the dip stick on the chain case and the better lighting. I'm a little disapointed as I would have thought that a new Tundra would perform better than the old one in the soft snow -- especially since it is in the utility catergory. However, I plan to solve this problem by installing either a 144x15 or 144x16" track -- I have checked and it can be done fairly easily. The neat part is that there is extra length under the hull of the 06 and it looks like the hull would still completely cover the 144" track without modifications. I may also switch from the 9tooth front sprocket to an 8 tooth to solve the gearing problem -- however there are problems with going too small on the drive sprocket so I'm not sure on this. It looks like the extension parts will cost around $130. Of course the big cost will be the track and if I get the 16" I would need to trim the paddles to make them shorter.

The bottom line is that both the old style and new style Tundra as well as the Freestyle are great simple reliable machines -- they each have their strong and weak points and with each it seems to me that you get a lot for your money.


5. Oops -- I forgot one thing. My primary clutch setting on the 2006 is still stock at 4 weights and that was fine with the gearing change. The 94 primary clutch is set up a little hotter -- about like 3 weights on the 06. I tried the various clutch weights and 4 seems best for my ears. However, I may try 3 again sometime because that was not so bad. The problem with the weight change is what I wanted was a little more only on the low end, but what happens is you get a constant increase in RPMs through the entire range.
 

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TUNDRAMAN DAN - YOU HAVE HIT THE NAIL ON THE HEAD WITH YOUR TESTS OF THE OLDER TUNDRAS COMARED TO THE 06 TUNDRAS. I HAVE DONE THE SAME TESTING WITH MY TUNDRAS AND CAME UP WITH THE SAME CONCLUSIONS. I HAVE ALSO NOTICED THAT THE 06 DOES NOT TRANSFER WEIGHT TO THE TRACK NEARLY AS WELL AS THE 93. MY 93 WILL LIFT THE SKIS AT WILL. I SET THE LIMITER STRAP ON MY 06 ALL THE WAY AND IT HELPED A LITTLE. HOW MUCH DID THE GEARING CHANGE HELP THE 06? DO YOU KNOW THE PART# FOR THE 47 TOOTH BOTTOM GEAR?
 

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TundraManDan said:
5. Oops -- I forgot one thing. My primary clutch setting on the 2006 is still stock at 4 weights and that was fine with the gearing change. The 94 primary clutch is set up a little hotter -- about like 3 weights on the 06. I tried the various clutch weights and 4 seems best for my ears. However, I may try 3 again sometime because that was not so bad. The problem with the weight change is what I wanted was a little more only on the low end, but what happens is you get a constant increase in RPMs through the entire range.
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You have the 'swinging arm' clutch in your '94 still? I put a Duster 94C on mine, just fine tuning it now.

BTW, I was able to get 12/27 gears and chain for $50 delivered.
 

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Discussion Starter · #11 ·
SISU said:
HOW MUCH DID THE GEARING CHANGE HELP THE 06? DO YOU KNOW THE PART# FOR THE 47 TOOTH BOTTOM GEAR?
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Hi,

The gearing change was significant - it did help. It was 2/3rds as significant as dropping one tooth on the top sprocket would have been (3 teeth on bottom = 1 tooth on top) -- however that is not possible to do (go smaller on top). Unfortunately, there is not a part number that I'm aware of for the 47 tooth aluminum sprocket. That part was something my dealer was able to obtain through Skidoo Racing. The first time they gave me the wrong chain (35 links - too short) so I had a false start on the first attempt to install. The stock chain is 36 links so 37 links is what worked. I had to remember that 1 link on that 06 chain = two teeth on the sprocket. I think my total cost for parts ended up at around $200+ which sort of threw me at first . . . I guess I was a little out of touch with today's parts prices being as 1994 was my previous snowmobile purchase.
 

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Hey, SISU
By lowering the limter strap all the way, did this effect the ski pressure / steering on the trail much? how does it handle and are you running in deep snow?
 

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RANDBY- LENGTHENING THE LIMITER STRAP DID NOT AFFECT THE SKI PRESSURE OR HANDLING THAT I NOTICED. BUT IT DID HELP VERY LITTLE IN THE DEEP SNOW. WHEN I RAISE THE REAR OF THE SLED THE STRAP DOES NOT SEEM TO BE THE LIMITING FACTOR OF THE FRONT OF THE SKID FRAME BECAUSE IT DOES NOT GET TIGHT. I HAVE TO LOOK FURTHER INTO THE ADJUSTMENT OF THE SUSPENSION. I COULD NOT SEE ANY ADJ. FOR THE FRONT SPRING OF THE SKIDFRAM. YES, I AM RUNNING IN DEEP POWDER.
 

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Discussion Starter · #15 ·
TundraManDan said:
My 1994 Tundra LT . . .
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Well, the 94 is currently the winner in the soft and deep but once my 144x16" track with 8" sprockets shows up, I'm pretty sure the 06 will win in all areas. The interesting thing is that there appears to be plenty of room under the 06 Tundra hull for the 144x16 without messing with a tunnel extension. The 8 tooth sprocket should resolve the gearing problem. Since the 06 Tundra is on a newer chassis, track extensions are not a problem to find. I will provide pictures and details on the install and result once it happens.
 
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