Monthly ArchiveJune 2008

Mountain Biking 30 Jun 2008 10:25 pm

Shimano XT M771 cranks for 83mm BB shell bikes Lighter

What?! you say…Shimano only makes Saint cranks for 83mm BB shell bikes. Well technically you’re right. However I’ve found a way around this weighty dilemma. If, like me, you have a bike with an 83mm BB shell and you refuse to run any other brand of crank–because you know that Shimano’s are simply the best–and you feel for whatever reason that you simply don’t need/deserve the strength and corresponding weight penalty of the indestructable Saints, then I may just have the solution for you!IH 6Point w/Shimano XT Cranksimg_2110.jpgYes…I know I need to wash my bike.

1st step; Get yourself a set of the Shimano XT M771 or M761 “big gear” cranks. They are different from the regular XT cranks in that they come equipped with a 48/36/26t chainring combo and a slightly longer spindle–thats the important part– to accommodate the extra frame clearance these rings would need. They are available in 165mm, 170mm,175mm,and 180′s too I think. Here’s the tricky part. They’re really hard to find in the States. If you’re a shop rat you may be able to get a set of these cranks through BTI, where I got mine, or S.A.C. (Shimano America Corporation). These cranks were designed as “trekking” or “touring ” cranks and are very popular over in Europe.

Now that you’ve gotten your cranks the modifications begin.

Remove the little black plastic spacer that sits on the bb spindle all the way up against the back side of the drive side crank arm.

If you’re using a chain guide of any kind, or your bike has ISCG tabs (which I’m pretty sure you’ve said yes to at least one of the above if you have a bike with an 83mm shell) Get out the hack saw–This part sucks cause you’re gonna do things that can’t be taken back. Ok deep breath–Exhale. Cut off all 4 of your new granny ring posts as flush as you can against the spider. Don’t of course cut off, or in any way damage, the part of the spider that you will be bolting your middle or big ring to. When cutting off the granny ring posts be careful not to hack into you’re bb spindle–I found that using the little dust boot that goes in between the bb cups worked quite well as a guard. It should be pretty obvious before you tackle this step that you will never again be able to use this crankset as a triple setup or run any chainring on it smaller than 32t.

Now use a file and try to file those hacked off granny ring nubs as flush with the rest of the spider as you can. You’ll have to believe me that every mm in this process counts so don’t skimp on this step. Again you can use the same bb cup dust shield as a bb spindle guard so you don’t nick the spindle.

Now that you’ve got everything cut & filed down. It’s time to start assembly. Oh and if at some point in this process you happen to face your bb shell down to say 82mm all the better. No spacers anywhere in the system. BB cups thread into frame– no spacers. No dust shield/spacer between the cups on the inside of the BB shell–It won’t fit (that’s why it doesn’t matter if you narf’d it up with the hack saw or file). I have an E-13 LG-1 chainguide bolted up to my ISCG tabs with no spacers in between the ISCG tabs & the “boomerang”. If you are using an E-13 like me you will have to bolt your single chainring on in the “big ring” position. If you are using a 36t or smaller ring you may have to trim the inner “cage” of the top guide for clearance with the tops of the spider as it revolves.

If you follow all of the above steps you shouldn’t have to take your cranks on and off 20 times like I did in this process. The spacing & spindle/crank overlap worked out perfectly. When all was said & done I ended up knocking about 3/4 lb off my bike, getting a great chainline, and getting better cornering clearance due to the lower Q-factor of this set-up. Saint cranks w/ single ring & BB 1030 grams vs. XT M771 w/ single ring & BB 730 grams. These cranks are listed as 900 grams w/bb but the difference between the 3 rings I pulled off and the single one I put back on was right around 200 grams.

Or you can just wait for the new Saint cranks to come out which are reported to be about 100 grams lighter than previous Saint cranks. My way’s still a couple hundred grams lighter though(give or take). And definitely a little narrower in the ‘ol Q factor. But, arguably not quite as strong and subjectively maybe not as cool looking.

Mountain Biking 18 Jun 2008 10:50 pm

Mt Ashland Super D

OK so it’s been a while (never heard that here before eh?). I’ve been out with injury for the last 2 months and didn’t figure anyone would be all that excited to hear about my “epic” 35-50 mile road rides I’ve been doing on my 32 pound Super D bike (Hey It’s cushy and better than running) or my exciting trips to the Y to lift weights. Thrill a minute around here. But I wanted to write about this years Mt Ashland Super D.

For those of you unfamiliar with the course I’ll try to lay it out for you. The start is at the Mt Ashland ski lodge at 6500 ft elev. from the start you can see the approximate area in Ashland where the finish is at about 2000 ft elev. Then you dive into a few miles of old road bed turned double track under a canopy of firs. After sprinting off the start & basically tucking & coasting for these first few minutes the joy ride comes to an abrupt end where you make a 180 and start up a 10% grade with about 500ft elev gain over about 3/4 mile. The worst part is after you make that 180 you’ve got a good 45 seconds to watch over your left shoulder to see if the guy who started behind you is making time on you while you’re suffering.

After the climb there is some pristine flowing singletrack for a few miles that eventually dumps you out onto a super fast decomposed granite fire road. A couple miles of drifty corners and it’s back to single track in the form of our local DH race course, followed by some swoopy single track and then a steeper bit of switchback track to the finish line. One thing I think a lot of the racers liked is that there are about 3 places on the 12 mile course where you’ve got a chance of a flat–So if you are cautious there you’ll more than likely get a clean run.

The race basically doubled in size this year to around 130 people which in & of itself is pretty cool. Mark Jordan from Decline Magazine showed up to cover the event & throw down a fast race run for himself of 37:52 to win the Semi-Pro field. Mark Weir of course won the event overall for the 3rd straight year–this time with a smokin’ fast time of 35:22. Here’s a link to the full Results. I spent a good deal of time getting advice about my broken wrist from Eric Carter & Ariel Linsley who have both suffered the same break and recovered from it (slowly but surely). Ariel’s still sporting a trick carbon fiber wrist brace from OTS, and Eric gave me a bunch of cool tips like cold lasers & bone-up. A bunch of the good folks from up the Friends of Capitol Forest crew made the trek down & had a great time. Everyone I talked to loved the event so I’m predicting it overflows 200 racers next year. Not hard when we had perfect weather–I’m talking blue bird skies, easy temps at the top for the start, unlike last year when we had freezing blowing fog at the top with about 150ft visibility. A little dust but not too bad. No snow drifts, no mud, no wind. Dirt was a good mixture between low rolling resistance & descent cornering traction.

Not racing sucks. But I did get some good pics of the race action. last half mile.The grimace of pain that wears Weir’s nameEric Carter diggin the DGAriel pre-railJon WilsonMark Jordan showing this corner like he did all the others