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Discussion Starter #1
I want more low end power from my 2012 550xp. I ride at 8'000 to 12,000 ft elevation all the time

I have looked into ways to get a lower overall gear ratio, but the clutching kits etc seem like a roll of the dice. Not to mention expensive.

So I'm looking at changing the stock 26" tires to 25" tires. Both front and rear.

But I can find very few tires in that size. (25x8,9,10 or 11 - 14). Candidates are Maxxis Ceros and ITP Terra Cross.

two questions: Do you have experience with these tires? Do you know any other 25x tires?

Thanks
 

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I don't have experience with those tires, but can tell you that the average clutch kits costs about $250. I can't buy 4 tires for that price around here.

Also, low end gains are much more with a change in clutching than with a 1" diameter tire change.

Have you tried talking with Adam at QSC about options and cost??


Rather be riding, instead I'm using Tapatalk
 

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Smaller tires also mean less sidewall which could lead to more flats if you ride on rocky trials.
^^Exactly what I was thinking.^^

You could do a little research as to which tires run smaller than the stated size. The Black Diamond XTR runs close to an inch smaller than the 26" stamped in the side wall. Just one of the many reasons I would never recommend that particular tire to anyone running 14" wheels.
 

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My exact thoughts have already been posted. New tires vs. clutch kit price difference. 25" tires on 14" rims def not digging that, especially if there true (or less) to size tires.
 

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If you ride at elevation that much maybe you should look at a tuner and airbox mods rather than tires or clutching...just another angle to consider since you need air to make power and there is less of it at elevation?
 

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Seems to me the clutching would be the way to go rather than narrowing down the tire choices. If you are riding at 8,000 to 12,000.... I'd say it would be a bit rocky and you need to pick out the tires that will fill your needs and get all the meat you can around those rims.... If it could be afforded, it would be nice to get the tires first and then dial in from there.

Curious, are the tires stock and are they worn out?
 

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Call me tomorrow after 8am Central. 651-707-6706 I can get you a QSC clutch kit together and a fuel programmer if needed to ge some more power out of it and get it to the ground better. Don't waste the money on tires. All the QSC kits are custom assembled to fit your riding conditions, style and needs. No such thing as a canned kit with them and I have everything you need to get set up and can usually ship the same day.
Ryan
 

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If you ride at elevation that much maybe you should look at a tuner and airbox mods rather than tires or clutching...just another angle to consider since you need air to make power and there is less of it at elevation?
And therein lies the problem. The fuel injection already compensates for the thin air, there is just less oxygen there to use. Airbox and tuner won't help much in that department. Only superchargers and turbo's really help to compensate at altitude. Or more CC's under the seat! (but we all know that big bore riders are only trying to compensate for something else, really no use for that much motor. :veryhappy: :veryhappy: :veryhappy:)
 

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Discussion Starter #10
Thanks for the suggestions.

Regarding cost - I need new tires anyway so the "cost" of going to 25" tires is zero.

As for more power - that is why I also have an 850 :silvia:. Even it gasps for air up on the trails.

Several buds have added superchargers to their snowmobiles. Thats pretty impressive but the mean-time-between-failures on their tricked out machines is about two hours.

I ordered ITP Terra Cross radials. (these seem to be going out of production). They seem like a good choice regardless of the size question.

The change is about 4% difference in final gearing ratio by my calculation. That will apply across the spectrum of speeds and hi/low range.

I'll report back to this thread on the results.

-c
 

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i would of went with 27 big horns or blackwaters
with a qsc high elavation cluch kit
 

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Discussion Starter #12
i would of went with 27 big horns or blackwaters
with a qsc high elavation cluch kit
I considered that.

But QSC say their high altitude kit is for 2,000 to 6,000 ft elevation.

My house is at 8,500 and I ride from there up. So not sure what that would mean. I suppose the clutch kit would help. But I can try the smaller tires for no cost since I need tires anyway. I'm interested to see the effect - if any.

The power loss at 12,000 is about 18% more than at 6,000. (figure about 3% for each 1,000 ft.

Picture is a Sample at 12,000.
 

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adam built my qsc for 10.000 ft i run 8500 plus 90% of the time in idaho
 

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Discussion Starter #14
adam built my qsc for 10.000 ft i run 8500 plus 90% of the time in idaho
That is good to know.

Did you see a real difference?

Maybe I'll try in on my 850.

Thanks
-c
 

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Qsc kits are all made specific for each user. They have some generally canned kits, but anything can be done for you. Give me a call when you are ready for a kit and we'll get you set up.
 

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yea it works good headed out now through the back countr to 3 corners idaho nevada utah all kinds of elavation and terane it wil be fun tearing up those 750 king quads that are going
 
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