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is buachail foighneach me
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Discussion Starter · #1 ·
The Nome race continues, but the McGrath race is over(for the bikes anyway). Considering the amount of comepetitors in the McGrath race, I think it's probably a pretty good indication of trends and efficacy of products. Maybe the best we have for snow riding.

The top three racers were within 6hrs and all on 100mm rims. The next two were 10 hrs back on 70mm rims(Eric might be on 65's still??) The next three were all on 100's as well, and then mostly 70's from there on back.

Does this mean that hundreds really are the only way to go for snow? Or would the top three have been just as fast on narrower rims? Am I really going to have to build up another set of wheels?

Greg, Jeff, Pete, care to add anything? Lou, Eric? Bill? Jay(when you get back)? Anyone else?
 

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Living the thug life.
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I had decided awhile ago if the stars ever aligned I would run 100's in that race. From what I gather huge parts of the trail are traditionally unrideable. The 100's would allow one to ride more and push less.
 

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sean salach said:
...Am I really going to have to build up another set of wheels?...
I think we can guess the answer to that :)

Only way to find out....
 

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How much does it weigh?
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I've got a better one... how many of those riders have their 100s lightened, vs, full weight.

If ones bike weighs 5 lbs less... that can make a difference.. especially if you say there is unrideable sections that you have to end up pushing the bike in.
 

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is buachail foighneach me
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Discussion Starter · #5 ·
The only one from that group that I know of who's 100's aren't lightened is the winner, Pete.... So there's that wrench in the works...
 

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In a race of 350 miles with what I can only imagine is a wide range of conditions the rims would certainly play a huge role. I imagine out of the top three riders Gregs bike might have been the heaviest.

I think what often puts the leaders in the front is a combination of preperation, proper equipment and most of all a confidence in the choices they make leading up to the start. The ability to race without questioning there equipment and preperation is paramount.

Greg essentially raced a new model bike, but the proven pedigre of said bike inspired him all the more.

An incredible race for sure!
 

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How much does it weigh?
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sean salach said:
The only one from that group that I know of who's 100's aren't lightened is the winner, Pete.... So there's that wrench in the works...
It's not the size, it's the motion in the ocean. :thumbsup:
 

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Fatback
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I'm still undecided about the 100's vs. the 70's for our conditions. The machining I did cut two pounds and left the rims absolutely bomber. I haven't spent enough time on them to feel like I'm able take advantage of their size. Tire pressure is more finicky than the 70's, which by the way, give the same tire width as all of the 80's-I measured the Darryls and the Flat Tops just two weeks ago. While out watching the Susitna 100, I rode the 100's with a friend who was on his 70's. I felt like I was working harder than I needed to for the conditions and verified this by swapping bikes. My seat of the pants guess was about 15-20% harder (conditions were firm). By the way, Jeff Oatley was riding a set of the same 100's I had just finished up for him. I think it was a huge disadvantage in the Su.
Unlike tscheezy, I think there is such a thing as too much float, or to put it differently, unecessary rolling resistance. Our conditions here are often very firm. The 100's roll slower, that much I know, but they can probably roll when the other rims cannot, yet, in those just barely ridable conditions, walking can be more efficient, not always, but most of the time.
If the trails are reasonably firm in the White Mountains race, there's no way in hell I'll be using them.
 

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Living the thug life.
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Wow, that looks like it took some time!

Good to hear your thoughts on the 100's. I have no experience with them. I assume there is noticeable difference in float when the trails go to pot though?

Interesting your comments about the 70mm uma rims. My friend remarked to me that my 80 flattops always looked bigger then his 70's (I am confident in my size unlike him, so I don't check others out). I measured my Larry's at 99mm, his at 92mm.
 

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is buachail foighneach me
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Discussion Starter · #10 ·
Any idea what tire pressure was in the tires you measured, and length of use, Logantri? I've measured brand new endos on both new Umas and new Rolling Darryls and got a 1mm average difference. My Larry, with about 6 psi in it right now, sits at 93mm, and my Endo with about 12 psi in it sits at 95/96. Both have been mounted, inflated for about a year and have about 2000 miles on them.
 

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is buachail foighneach me
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Discussion Starter · #11 ·
Back to rim width though, I wonder how tire profile affects handling as well. Would the 70's handle more quickly, working better with more rider input? Riding style might come into play.

The guys at the front of the Ultrasport this year had much worse conditions on the west side of the Alaska Range that those of us in touring mode. I don't think I pushed more than 5 miles after Rohn, and I probably could have ridden a lot of that, but was pushing to keep warm.
 

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Fatback
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I used the 100's for the same reason that I took a -40 sleeping bag. Better to err on the side of caution. What kind of pressure were you running during the day Sean? Did you get a chance to ride alongside anyone with wider rims that was similar in weight?
Interesting side note-my next door neighbor's uncle is in the Iditarod (Paul Johnson) and he had to send a dog back to town because of a sore shoulder. He said conditions were too soft and the dog was worn out. Maybe he needed some oversized booties.
 

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Living the thug life.
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They were both at 10psi. If you hold the tires tread to tread you can see that my friend has a reason to "admire my girth". Again, it was because of his comments that I even looked. Both are 120tpi Larry's from this year. Mine might have had a little more mileage on it at that point, but not much. I just happened to have both wheels at the shop to treat the freehubs and I whipped out the calipers for curiosity.
 

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This place needs an enema
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Sounds like you're a bit conflicted, Greg. No one would begrudge you the 70's for Hillside/Kincaid riding where there's almost always a hard base underneath. Even 50's can work there, though IMO 70's are a better compromise for most folks.

And this year's Su race? A sidewalk, by most accounts, so of course the 70's make more sense. Even snowcats worked well on that course this year.

But when you start talking about getting past Finger Lake, into the range, and out the other side, historically there isn't a lot of reason to go with anything other than the fattest rims you can find. Float is one reason why--more air volume means more float, so you can ride a higher percentage of punchy trails. But the benefits of the hundies go beyond float. A more square footprint keeps the tire (whichever one you're running) from squirting out from under you when the snow gets wind affected. Once all those little arms are broken off of the flakes and there's nothing left to hold them together, a wider rim allows you to ride more before the bike squirts out from under you and you have to dab and/or walk a bit before getting going again. Lastly, the added mass of the 100mm rims *helps* in chunder and rutted conditions, as that added mass isn't as easily deflected, meaning that again, you end up riding more than if you had narrower/lighter rims.

Those that want to snivel about a few grams worth of rim weight aren't going to be allowed into the ITI anyway--prospective racers take note, it is an *invitational*!

And rolling resistance? I can't say I've ever noticed an increase due to running the wider rims. But I'm certain that I ride more with 100's than anything narrower, and last I checked riding is faster than walking.

MC
 

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is buachail foighneach me
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Discussion Starter · #16 ·
Greg, I dropped about 2psi off of my back tire on the first day, out of the big swamp with Bill. After that I never touched em. What I posted above(6/12) was what I ran for the whole race. I'm sure the temperature affected the pressure at any given moment, but I never took my pump out of the bag.

On the first day I was riding with Bill, who was on 100's, and was able to ride all of the punchy stuff he was able to. On the last two days I was riding with Joe(70's) and Janice(100's). Both of them are a bit lighter than I am, and I don't think I was nearly as tired as them, simply because I was physically prepared to keep going to Nome. I was able to ride a little bit more than they were. It's pretty tough to compare one rider to another without taking into account each riders air pressure, riding style, level of fatigue, etc....

Like I said though, the people behind the top 10 had a much firmer trail than you guys did, I think. I know that Joe, Janice and I were all casually riding past a lot of day or two old wind swept footprints.
 

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mikesee said:
Those that want to snivel about a few grams worth of rim weight aren't going to be allowed into the ITI anyway--prospective racers take note, it is an *invitational*!
Come on Mike there were a lot of seriously drilled out rims in the race. Maybe nobody sniveled but they did at least count a few grams. It looks like the rims coming out of the shops do still have some safety factor built into them. Some of the home drilled ones I've seen on this forum, not so much.
 

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is buachail foighneach me
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Discussion Starter · #18 ·
I don't think Kathi is allowed to snivel at gram shavers as long as she's riding that fork/rack of hers....
 

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All my riding has been on 100's...with the exception of the few times I've ridden my GF's Fatback (with 65's)...I enjoy the 100's ride quality more...but I am slow...even on Snowcats...

-edit- I'll definitely be on my 100's when I do Aniak to Bethel (150) next week...
-edit- nevermind...training new guy at work...
 

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How much does it weigh?
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You guys make me jealous... I'll need to travel up to Alaska to ride some good snow one day.

Having said that... comparing my Fatback to a regular bike.. I'd say it's not much harder if at all to ride any kind of distance on. At 10psi it rolls great on the road.

When the conditions get warmer though, and the snow turns into slush.. forget it.. might as well walk, it's just too slippery.
 
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