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Discussion: dumping gears

in: Bash; Bash > 2017-05-08

May 9, 2017 6:27 PM # 
Mr Wonderful:
Does a big/long press drop 3-4 gears a la Shimano?


38->24 front while staying in 18 back, 2.111-> 1.333

30 front while in 14->24, 2.142 -> 1.25 (1.429 if only 3 jumps than 4 jumps)

Would then not be hugely different.

Re: bad lines...on my better days when energetic, I am having fun hitting the crappier lines for skills practice. Granted, timid trails, so just a few extra roots.
May 9, 2017 7:01 PM # 
I don't know if a long press drops multiple gears! Good thought - I will find out and answer here.

On our local trails, there are occasional rooty, rutted uphills and sharp curves where a good line makes the difference between possible and impossible for my 26er. So far it looks like my 29er can roll over most things if it is flat or downhill but I still need to practise more rooty uphills to see where my limits are. Rolling over uphill obstacles may sometimes require more watts than I can provide. The big wheel up front makes the hills feel a bit steeper too.
May 9, 2017 7:57 PM # 
Carbon's Offset:
Yep, a long push should downshift 3 gears or so.
May 9, 2017 11:56 PM # 
Your rear brake probably needs some time to break in. New pads and rotor can be loud.

The other thing I remember personally from the 26/29er transition is that you have alot more grip on a 29er than expected. So hills which I thought I might lose traction on I could just spin up and I could also lean the bike further when cornering before losing grip.

And with newish disc brakes I wouldn't lose sleep about them being upside down for too long. They seem to be pretty good at fixing themselves if you pump the levers a bit (at least Shimano XT's are).
May 10, 2017 12:04 AM # 
Also, you can justify a bike stand for maintenance now.
May 10, 2017 2:35 AM # 
I need to do maintenance now? ;(
May 10, 2017 2:50 AM # 
Yup, I can do a long push to downshift a bunch of gears so that will work if I miscalculate. However, it seemed like things got out of synch for awhile after that. The gears did some jumping around on their own under load, which they hadn't done before. So I'll save this for emergency downshifting.

I am feeling better grip on banked turns but not on rooty climbs. I'll try lower tire pressure next week after Storm since we'll be doing some road riding there.

I'm getting the dropper post installed tomorrow - maybe. The one that came with the bike was too high and they're thinking the new one may be too low. So maybe I'll just be getting some money back. :(

I'm also getting a minor tune-up while I'm there now that I've ridden the bike a bit. They can take a look at the noisy brakes and let me know if I'm wrecking something. The front brakes are smooth and silent while the rear brakes sound like loud metallic scraping. If it's not causing damage, that's fine but I want to be sure.
May 10, 2017 1:04 PM # 
I've been guilty of too much tire pressure for pretty much most of my time on MTBs. I just hate inefficiency on hard-packed roads in AR! In any case, I'm at 30 psi on my new MTB and CO did a quick calculation that he knows to see if it was too much or too the end, it seemed about right. Perhaps he can do the same for you. Point is, that the right pressure certainly helps the tires to grab on the terrain much better, ultimately giving confidence from assured traction rather than ping-ponging around too much between obstacles.
May 10, 2017 1:56 PM # 
CO gave me that calculation in another AP comment thread so I'll try that next week after Storm. The bike shop is telling me to stay in the 22-25 psi range so that's what I've tested so far. CO's math puts me at 17 on the front and 20 on the back.

Like you, I've often ridden off-road at higher pressure than I should because of AR road sections so maybe I just need to get used to a different feeling. Mostly, it's been great but on this one climb I've been testing, it isn't a better feeling so far. I've also got different tires but my old ones were almost bald so it's hard to imagine they helped me grip better. I will have to go back on my 26er since 'Bent says that climb has eroded since last year so maybe it will just be hard on both bikes.
May 11, 2017 2:13 PM # 
Back to Barrie today for a quick tune-up and two add-ons that were special-ordered but neither of them worked out. The original dropper post was too high and the new one is too low. The bike shop had to look far and wide to find this lower one so it may be the end of the line for me and dropper posts.

The other accessory was a special Fizik seat bag to work with the dropper post but that's a non-issue for now. Also, the bag is weird.

Those of you with dropper posts: How do you carry your stuff? Spare tube, multi-tool, chain link, tire levers etc. And where do you put the rear red light that is usually mandatory in AR?
May 11, 2017 2:18 PM # 
P.S. The rear brake, which has been noisy since I brought the bike home, was silent when I tried to show the problem to the bike mechanic. So I fixed it by putting the bike in a van. I'll remember that for future problems.
May 11, 2017 2:29 PM # 
With the dropper post now, I don't put anything on my bike. It all goes in my pack, instead. CO has a seat bag on his, however. My choice is mostly to do with wanting my bike as 'clean' as possible for maximum manoeuvrability and light-feeling on the trails.
May 11, 2017 3:12 PM # 
Carbon's Offset:
Carbon and I have a seat bag that clips under the seat without needing to strap around the seat post. I will look at what brand it is and let you know.
May 11, 2017 3:26 PM # 
Thanks, all. I'll use a pack sometimes but I'd like the option to have everything on the bike so I can just ride with a bottle sometimes. Boy, those 29er tubes are big 'n' heavy!!

Yay, the bike shop realized they'd sourced a small dropper post from a third party when they could have ordered a medium. They now know why Pivot weirdly says that their small bikes are for riders 5'10" and taller. (I have a medium, which fits well otherwise.) It's based on Fox dropper post height (higher than some other brands), which is strange since they only offer dropper posts as an option.
May 11, 2017 7:01 PM # 
Carbon's Offset:
Here is the seat bag we have

It sits nicely, slides out of its mount if needed but otherwise you just access it through the drybag-style roll closure. Waterproof. We got them for the same reason you are spotting: having a mounting strap around the seatpost may be an issue with dropper posts.

It is small but able to hold what you have listed. I have a 29er tube, 2 thick Pedros tire levers plus a third regular Zefal lever, very small multi tool,, chain tool, patches, tire boot, spare link and spare derailleur hanger in mine. That fills it pretty full. I could squeeze another tiny thing or two in there (or maybe a bigger tool), or maybe give the roll closure one less flip and still close it.

It doesn't bounce or wiggle. I don't notice it when I move the seat up and down but I am able to drop my seat low enough that I can rub the pack with the tire for a second if the suspension comes way up due to landing a large drop. This is because of my frame size versus my leg length; I barely have any of the stationary part of the seat post extending out of the frame, so most of my seat post that you see is droppable (I'm making up words. My vocabulary is a bit janky). I hear it buzz for a second if the tire ever rubs the seat pack but it still hasn't caused any wear to the pack, so it is a non-issue.

It does not have a clip for a rear light. You could probably attach one to the bungee loops on the side that you use to close it. Maybe not ideal for direct visibility for traffic etc but enough to satisfy race requirements.
I used the seat pack for WT and had a dog leash tow system attached under my seat as well. If you or anyone is curious, I'll have to remember how I positioned them both or look for some photos. It worked well and wasn't tricky.

FYI, I raced that bike at WT with a 1x drivetrain AND had reduced the gearing on the front ring, yet was still able to hold the pace on the pavement. Must have been the advantage of the soft, wide tires ;) (that IS what the Schwalbe research claims.... lower pressure and wider tires roll faster... except for on pavement). Truth be told, I was almost at my hamster cadence limit but still managed.

Quite happy with the seat pack. They make other sizes if you wanted something bigger for AR or joining Revy for a ride to Argentina.
May 11, 2017 11:37 PM # 
I think I'll get a new bike and a dropper post just so I can use the knowledge dropped in that review.
May 11, 2017 11:41 PM # 
Carbon's Offset:
May 11, 2017 11:43 PM # 
Carbon's Offset:
Lots of good droppable facts contained here. Nothing janky.
May 12, 2017 1:39 AM # 
My dropper is on the fattie, which has tools in the stem (chain fixing stuff) and attached to the bottom of the bottle cage (a general mini kit). I do have a bag that clips onto a Fizik seat - it is a nice setup and doesn't touch the post, but it is too small for enough to fix a fattie flat, so that stuff would have to go in a bag. The Fizik bag just barely holds a road spare and air.

I have rear lights that nicely mount on the rear triangle, so I don't need anything on the post.
May 12, 2017 3:17 AM # 
Wow, thanks for all that great info, everyone!

@CO, I was thinking that my bag may bump the rear tire sometimes between the dropper and the suspension. Of course, I don't live in the Rockies like some people so those moments won't be as frequent.

Perhaps the most educational thing I've heard recently came from the bike mechanic who seemed surprised that I was surprised at how complicated things were getting. "Oh, *nothing* is simple with bikes," said the man who works on bikes for a living. I guess if I wanted simple, I could have bought a car.
May 12, 2017 12:01 PM # 
There are still simple bikes. They just aren't as exciting to buy.
May 12, 2017 2:30 PM # 
Crash likes her rigid single speed. Only thing simpler is a fixie. Conversely
I think I have taken complexity to the pinnacle.
May 12, 2017 4:36 PM # 
I checked my Fizik seat clipon bag with the dropper. It clears the giant rubber easily, but wouldn't if I had a rear suspension.

This discussion thread is closed.