Bikepacking gearing

[bncrshr77]

Hello,

I'm switching to a 29er and have a few questions..

I'm planning on the Cococino 250 this year and the ATR 300 and CTR 500 next year..

I've been doing tons of research and have pretty much decided that I want to stick with my good old 3 x 9 XTR drivetrain..

I'm thinking that I will want all the gears I can get due to the widely varying terrain along these routes...I would hate not having my low gears for grueling climbs and would miss my big gears in some sections..

What are your thoughts???

[boddunn]

My girlfriend had a 700C Kona which had a crank with road size gearing and it was too big for her. I put my old crank on it which had a standard 42 chainring and the gearing is now exactly the same as my 26" wheeled bike that has a 48 chainring. That doesn't help that much does it?
 Best thing to do is use Sheldon Brown's gear calculator, you can compare like for like and get it geared up the way you're used to.

[AZTtripper]

If you want to be able to spin, if you tend to spin rather then mash, you might want lower gears for bikepacking.

Several riders I know who have done the rides you are talking about are running 2x9 with a 20x36 granny.

Most have made the upgrade by using Action Tec cogs. http://www.actiontec.us/ti&steel.htm

As long as you have a steel freehub and not a Chris King or other soft metal one you can use one of these http://www.bikepacking.net/reviews/bike-components/actiontec-36-tooth-cog/ just drop one of the smaller loose cogs off of your cassette and put this on behind it.

To get the 20 on the front http://www.bikepacking.net/reviews/bike-components/actiontec-20-tooth-chainring/ if you have a standard 4 bolt crank you may have to use a file to remove some of the top of the crank hole (otherwise the chain tends to jump off).

I have done both the Coco and the 300 with 20x36 gears and it does help on some of the climbs. There are times when it's just to low and slow but you can always drop a cog when you need to. Then it is nice to have the really low resting gear.

As for the big ring, you will use it if you have it but not that much, and if you didn't have it you wouldn't miss it.

Hope that helps. I haven't done the CTR but I have done both of the AZ races. The Coco is a fun one, are you doing the stage race, it's more of a group experience with everyone camping together. Hopefully the AZT will be completed in the White Canyon area. This years course was a little convoluted due to the trail being incomplete and the old route had a construction blockage.

Best of luck

Tim

[bncrshr77]

Thanks for the great info!!  I'm planning on building up my wheel with DT Swiss 240 hubs so I will need to do some rearching about putting the cogs on that hub.... I agree that if I'm used to riding without the big ring up front I might not miss it!!

[bncrshr77]

Lets say I have the new XTR M980 2 x 10 trail crankset with 26 - 38 rings.....Could I just change the 26 ring to whatever smaller Action Tec ring I wanted and leave the original 38 ring???  Would they work well together or should I change both rings out??  Sorry for the questions but I get more and more confused about this when I read the 8 page threads on the subject...

[AZTtripper]

If you go 2/10 that will get you the 36 tooth cassette in a nice clean package.

Not sure what the bolt spacing is on the 10 speed cranks.

The old standard for 9 speed cranks was a 4 bolt 64 mm. That's a little too big for the 20 tooth thus the chain jump.

There are 5 bolt 58 mm cranks that eliminates this issue. I have the Surly Mr Whirly http://surlybikes.com/parts/mr._whirly_crank/ but to be honest it has it's own issues. It's complex and heavy but the bearing can be lubed where a lot of them are sealed.

You could go 2x10 with a 9 speed crank and at least get 22x36 pretty hassle free.

Sucks that neither Sram nor Shimano wanted to make a decent 36 tooth 9 speed. Shimano did a heavy low end one but they both jumped on the 10 speed band wagon and want to force us that way.

Pretty sure you could use the Action tec with the DT hub.

You'll get there all in good time.

Tim

[bncrshr77]

After a bunch more research today it does seem easiest to go with the XTR 2 x 10 setup.... 11/36 rear from the factory....Front trail version is 26/38 so I I will need to either change both rings or find out what the smallest ring I can go down to and still have good shifting with the 38 is....Action Tec makes the whatever rings I need so I should be good to go!!

Has anyone used something like this to protect their rings or do you have much trouble out west??  http://www.mountainracingproducts.com/mrp/xcg/

[AZTtripper]

Looks like that XTR crank does use a 64 mm bolt pattern but It's a big jump from 20 to 34 not sure if it would work to go for that big of a jump 20 to 38 that is.

Yes you will want some kind of bash guard most people I know have the bash guard as a ring that replaces the old big ring. Why not just reuse your old 9 speed crank?

Actually that's a other good point about a 2x set up with the 34 and a bash guard you gain some ground clearance. Not sure about the CTR course but the Coco has one section dropping off of Williams Mountain there are lots of rock ledge steps. The AZT has some of these as well.

What kind of bike are you getting do you know what the BB height is? 

[bartspedden]

As far as the chain guard is concerned, if you have ICSG tabs it's not a bad idea to run one. While it's clearly not needed it does ease the mind when you're on the downhill.  The CTR has 60K feet of climbing, which means that there's also 60K feet of downhill too!  If I had the tabs I'm pretty sure I'd be running it because my gearing of choice is 1x10, 30T on the front and a 12x36 on the rear, so it sure would be nice to be able to protect that fragile little 30T chainring!

[bncrshr77]

Well, here goes.....I know you're all gonna tell me it's not a good bike for bikepacking.....But it is a good bike for everything else I do and I only want one bike.....

Santa Cruz Tallboy....BB height 12.8"   Fairly light and from tons of reviews it climbs like a billy goat...

My last bike was stolen so I'm starting over from scratch with bike and parts.

If I can find a good deal on an XTR 970 triple crankset I will get it and ditch the big ring for a bash.  If I'm not happy with the 22t for a granny I will get the 20t.

Since I have to buy a cassette anyhow would it be smart to go ahead and get the complete cassette in TI from action tec instead  of spending almost as much money on an xtr cassette and then buying the single 36t cog???

[AZTtripper]

Looks like a decent bike to me I had a Blur but sold it off to go 29. There was one at last years Coco ride. 6.64lbs that's not super light but you could do worse. A full Action Tec cog set would be pretty sweet should be fine with the DT Swiss steel freewheel. The shop guy had me convinced to go that route when I was building the Blur but I had already been sold on Chris King and they would chew up the light weight freewheel.

One thing I noticed looking at the frame it looks like you will have room for a frame bag under the shock. The other thing is it looks like you will have space to grab the frame above the shock, at the back end of the top tube. While this may not seem important to the average rider trust me it will be very handy when bikepacking. If you use a large seatpost bag (the most common setup) it's hard to grab the seat like you normally would. A buddy of mine bought a Pivot and the first thing he notice when bikepacking was that the shock got in the way when he went to grab ahead of the seat post. During this years AZT 300 I was out on Oracle Ridge doing some trail work. Kurt R was still out in front at that point and he stopped to talk with us for a second. I noticed he had the new Spearfish and asked how he liked it. His only complaint was that he didn't have a good place to grab the frame.

Best of luck with the new rig let us know how things come together. I would like to say I'll see you at the Coco but I may not be able to make it this year.

Tim

[bncrshr77]

I'm going with the Carbon Tallboy so the frame will be 5.1lbs...
I will most likely go with the full action tec cassette..
I've already been looking into the clear carbon frame protector tape to keep the frame bags from rubbing too much....And I'm planning on the large seat bag as well..
I was looking at the salsa spearfish for a bit but decided the carbon tallboy was lighter, supposedly climbes as well or better and has more plush suspension for the looooong downhills in the mountains..
Too bad you might not make the coco....Im planning on getting a few of my friends in on it as well so it should be a good time and I should be able to learn a lot from the other bikers!!
--Tom--

[AZTtripper]

Wow full carbon should be sweet, yes some will say it's not the right bike but I should think Santa Cruz has it figured out, and they have a good warranty policy.

Just to be clear when you say large seat bag. There are two guys making the over sized seat bags meant for bikepacking. And they both make two sizes. I have the regular size and can fit a lot into it. As far as I know the largest one is meant more for winter. I thought I wanted the extra large one but my buddy with the Pivot pointed out that it would stick out too far behind the seat. The key thing being able to get behind the seat on the down hill sections just as you normally would.

Tim

[NT]

I've been running a 20 tooth ring up front for nearly a year now and couldn't be happier. Not sure I need more gears, but thinking about it all the same...

Does anyone have experience with the 36 tooth cog from this guy?
http://www.ebay.com/itm/36-Tooth-Cog-for-Mountain-Bike-Cassette-36t-Sprocket-/260936517924?pt=Cycling_Parts_Accessories&hash=item3cc1074924

He also makes a 13 tooth to replace the two smaller cogs and an oversized lockring. All meant to work together. Just wondering if anyone here has used them. Also wondering if it would generate too much torque on a standard freehub or if one should get one of the hubs made by shimano for their 12-36 cassette. I've got a dt swiss 340.

[AZTtripper]

A 36th tooth can tear up a freewheel old style XT's can not handle it. Also 20x34 will take one out. Pretty sure the DT swiss can take it. Pretty sure that's what Mike C likes for Lace Mine 29 Wheels. Seems like he posted up on how easy they are to fix once you know what you need. Not that many people have issues.

[bartspedden]

For what it's worth the 2010 Mavic freehub on the crosstrail's has more or less worked for the last two years for me.  I was running a 30T chainring and a 12x36 cassette for the first year and then switched to a 32T chainring after switching to the E13 singlespeed cranks. The 30T chainring didn't fit well because the bolt tabs were just a little to long and the chain would hit them. I did have to rebuild the freehub last week because of too much slop in the freehub. It only cost $16 for a new delrin ring and some mineral oil from hub doctor and after a couple hour ride this weekend it seems to be just fine.  From what I've read it seems like I should of been doing the maintenance every 500 miles or so.  I probably had upwards of 4000 miles on it.  And by maintenance I mean just taking the freehub apart, cleaning and lubing it. If I had been doing that I wonder if I would of needed the new bushing?  So, from my experience, the mavic freehub is up to the task of a 36T cog too.

[mtntraveler]

The full Ti cassette is nice in that its light and all in one package, but it may not shift as well as a Shimano cassette due to the lack of shifting ramps  on the individual cogs.  A friend of mine a while back found it to be a problem.  Just my two cents