Fullcount

Question,

I have two bikes set up for touring. Bike A has a low of 16.8 gear inches and a high of 96.3. Bike B has a low of 21.1 and a high of 113.5.

Bike A has a front tire clearance issue between the front fender and tire at the fork crown. It also has some heel strike issues on the wheel base when set up with bags. If I were to use this bike, it would be in combination with a trailer.

Bike B is a LHT Disc Trucker that is built for bags and has good breaks for the downhill.

Bike A is lighter than Bike B by about 5 pounds.

I am going on a small tour that will take me over the Blue Ridge Parkway this May. Due to the clearance issue and the potential for a rock getting jammed between the tire and fender on a down hill run, I am hesitant about using Bike A, but it is lighter and has a better gearing set up for climbing mountains. The weight advantage goes away if I have to pull a trailer.

Bike B is heavier and not as good a granny gear as the other bike..., but no fender concerns.

So here is my question - how low a gear set do you need to climb the Virginia Blue Ridge? Does 16.8" really present that much more of an advantage than 21"? My thinking is that your legs can only sustain so many RPM's for so long before your lungs explode. Am I correct in my thinking? I am leaning towards Bike B due to the disc brakes and the elimination of doing a front wheel flyover on a downhill run.

On Bike A, I could just take the fender off and eliminate the risk of the rock jam. But at the expense of water and dirt spray into my front chain ring.

Your thoughts and recommendations are appreciated.

mstateglfr 

Use the LHT and swap out the smallest ring for something a little smaller? You wouldnt need a trailer, you would have the brakes you like, you wouldnt be worried about a fender issue, and you would have lower low gearing. 21" is pretty low as it is though.
But what is low is relative.

fietsbob

Narrows down the respondents to those who rode the route you plan to take ..

I didnt so I dont really have a reply of the precise pre testing you seem to require.

granny tooth count 1/2 the big ring ?

indyfabz

How can we accurately assess how low a gear set you need? People's abilities vary. Also missing in the equation is your load. A friend of mine did the parkway and more (Philly to Atlanta) on his road bike with 50/34 compact and a 11-25 cassette because he's a strong rider and was credit card touring.

With that said, if you are really worried about struggling and not having a good time, err on the side of the lowest gearing.

BTW...You will notice the difference between 16.8 and 21.

IK_biker

Have been riding the Appalachia overall, and the Blue Ridge portions in particular for about 12 years, I personally have been very comfortable with 25 GI when unloaded, and with 18 GI when loaded.
In my vocabulary, "loaded" means about 15 lbs of luggage (20 lbs tops with extra water and dinner food for the camp) while "unloaded" is with an audax-equipped bike (lights and a handlebar bag with raingear, extra clothing & gloves, and some food). I don't have any experience with cycling with heavy luggage.

We don't know how strong a rider you are - only you can decide what is the better gearing for you.
The difference between 16.8 GI and 21 GI is quite big, and very noticeable.

I don't share your view about lungs exploding at high RPMs, based on my 51 years of bike riding. My main concern has always been keeping my knees from exploding. My normal cadence is 85-95, and I am known to hit 110 every now and then.
Even with my 18 GI setup, I am occasionally forced to drop to about 40 RPM - I'm not a super strong rider and the multitude of very steep inclines of the Appalachia keep challenging me.
In my book, fenders become important only if it is cold (below 55°F), otherwise rain in warmer weather is not that much of a threat and I don't justify the extra protection of fenders.

bradtx

Fullcount, If Bike A will require a trailer, the five pound advantage becomes a five pound, or more deficit and the lower granny it has potentially becomes more important. I (we) have no clue as to how much gear weight you'll need to carry for your tour so I'm just guessing at around 30 lb.

Brad

chasm54

I don't know the Blue Ridge Parkway, and I don't know how heavily loaded you will be. But at over 60 years of age I very, very rarely need a gear lower than 22 inches. Like, almost never, and I do tackle steep stuff. On the other hand, I never tour with a bike/load combination that weighs more than about 75lbs, usually less.

Fullcount

Gear - I guess I will be in the 20 lb range. As far as how strong a rider, I would classify myself as weak on hills. Just not enough of them around here to make a regular training regime on. And....this is my first tour. I guess that is the reason I am a little nervous about taking the right bike.

I have only been back riding for three years now. Started it because my knees were weak while backpacking. Knees are stronger now, but I am 207 pounds and a little inexperienced. Excited about my first tour, just want to enjoy it.

Thanks for the suggestions. I have been reading in some other areas and it seems folks under 25 GI are doing fine. If I am at 21, I think I may be okay. Guess I will find out in May.

saddlesores

i did part of the blue ridge many moons ago. re-purposed
mountain bike with front bags and pulling a bob. if i recall,
the parkway itself doesn't have too many tough climbs....it's
getting up there in the first place, then down to the camp-
grounds at night, and back the next morning. steep hills,
but not terribly long.

i think i had about an 18" gear, which is mighty nice and
much better than a 21" gear. i don't stand on the pedals,
and don't increase my spin rate going uphill. try to keep
the cadence about the same or slightly lower than on
flat terrain. lungs won't explode, and you can happily
spin uphill for hours on end for moderate inclines, up
to 10%, more than that and cadence drops big time.

go with bike B. it's designed for the load and should be
much more comfortable. switch to smaller front rings.

Fullcount

A question, because I really do not know. At 40 rpm, how fast were you going? And how hard were you working? Reason I ask is that I too ride at about 85 - 90 PM with an occasional burst into the 110 range. But on a hill..a long Appalachian hill, how long can you sustain the climb when you are only moving at 2 -3 mph? I guess what I am asking is when should I decide it is no longer worth pedaling and just get off the bike to push?

Jim Kukula

I don't know anything about the Blue Ridge Mountains. But my bike has a low gear of about 17 inches and I use it constantly here in the Catskills. Lots of 11% grades.

I think the practical limit for low gears is how slow can you go before you tip over. A cadence of 90 with a 17 inch gear is maybe 4.7 mph. Tip-over is probably 1.5 mph zone. So probably a 6 inch gear is about the lowest gear that would make any sense for normal use, e.g. not pulling up tree stumps. Practically of course it is not so easy to get a 6 inch gear at all, plus it's always nice to have a gear up around 90 or 100 inches, so that is a huge range. So compromise is needed!

Squeezebox

When to walk? When you going so slow that you risk falling over. But slow is a skill to develop.
In "76 I did 2 weeks on the Trans America. I was young and strong. I got across the the Blue Ridge on a 3x5 with a low of 38x28 . The climbs on the Blue Ridge were longer than Missouri but not much steeper maybe less. But getting onto the Blue Ridge was tough. So you should be okay on the BR itself, but getting back up onto the BR after dropping down into town to resupply will be the hard part. IMHO from '76.
Later I did get too the village at the base of the Matterhorn. That was worse. I failed twice at trying to cross the Alps, in "81.

Tourist in MSN

Fully concur.

To elaborate further, I find that I need about 3.5 mph to be able to maintain good control and stay upright. A little slower and I am weaving back and forth and slower than that I can't stay upright.

When I setup my expedition bike, I could have picked any gear I wanted because it is a Rohloff bike and all I had to do was decide what size chainring I wanted. I calculated that at 3.5 mph (my lowest speed where I maintain good control), 72 cadence (the slowest cadence I can maintain and still be pedaling smoothly) I needed a low gear of about 16.5 gear inches. If it is too steep for me to climb with that gearing, I get off and push.

And to complicate matters further, I will call it quits if my heart rate gets too high, which further limits how fast I can pedal up really tall and really steep hills.

Thus, if it was me, I would take the bike with lower gearing.

IK_biker

There are two factors in this equation - when to dismount.

The first one, as already mentioned, is the bike-handling skill at low speeds. Mine is OK, after many many years MTBing technical singletrack, and yet I find it marginal @ 2.5 mph, especially with cross-winds, heavy traffic and narrow road shoulders. I can go to 2 mph for short stretches under 1/2 mile if it is not very windy, but this takes lots of concentration and is outright unpleasant, especially when tired after a long day. 2 mph happens to be the speed @ 40 RPM with my 18 GI setup.

The second factor is the heart rate. I'm 57 and have noticed lately that approaching 180 bpm puts me in a critical zone, and I can not sustain anything over 180. My max I have hit on a few counts this last year was around 200-210, and for me riding @ 180 is neither healthy nor smart.
This is perhaps close to what you chose to call "lungs exploding". In such situations, I need to stop, and take a break until my heart rate gets down into the 120s. Pushing the bike under these circumstances is an option, but I generally don't do it as I very seldom run into this scenario. Besides, here in the East US (Appalachia, Catskills, Adirondacks, the White and the Green mountains) such extremely steep inclines are not very long, and a short 5-minute break is enough to get me going again.

Two more comments.
As other mentioned, the Blue Ridge Parkway itself is not super-challenging. It is its neighborhood which requires low gearing, and my experiences were not about the Parkway per se. And, since you shared your relatively limited experience and this being your first tour, I suggest you forget the trailer, take the LHT, but put a smaller granny ring on. Not having a low enough gear is something you could get over on a 20-mile ride, but can entirely ruin your trip on a multi-day trip of 80+ milers.

Fullcount

Somehow, I communicated incorrectly. I will not be riding the BRP for any length, I will just be crossing over it at Fancy Gap. Then I head down towards the Grayson Highlands on my way to Damascus. So really just the big climb up. I think I will take some of the advice here and get the granny gear fixed on the LHT. Presently I have a 26,36,48 on the front and a 32 - 11 cassette with a 26" wheel. On the Trek, it is a 27.5" wheel and a 12-36 cassette matched to a 22,32,42 front chain ring.

Any ideas on how to change the LHT to get down lower at a reasonable cost?

Oh, and by the way, if you want to follow along, here is the link to my route and ride: https://www.crazyguyonabike.com/doc/FullcountTom

Walter S

I've ridden the blue ridge mountains for nearly 40 years. I concur that nobody can say what you need. But I have a couple comments. The blue ridge parkway is not real challenging. Max grades are 6-8%. But how are you getting on the parkway? And will you get off to go into local towns etc? That's where you're going to find some of the steepest climbs in the country. 15% grade is not real uncommon. There's steeper but rarely.

My bike is a disc trucker and my low gear is 16.8 GI. It started out higher than that but I found myself needing to be too choosy about what I'd take on for a loaded climb. Even at 16.8 I wouldn't try brasstown bald. But I rode the 14%+ grade on Richard Russel Parkway recently and did fine. A steady speed around 3.5 mph. I couldn't enjoy that loaded with 21 GI.

bikenh

Don't forget, there is more than one way to ride a bike. I rarely stay in the saddle to climb...VERY RARELY, totally never do while on a trip, only do it while riding with locals on occasion. Getting out of the saddle, unless you are fighting a nice head wind, makes it much easier to climb, err, means you don't need as small of gearing. It also gives your butt a chance to rest without having to get off the bike.

I rarely climb slower than 4 mph and rarely climb out of the big chainring...like others have said, your experience and fitness level will play a major role in how small of a gear you should plan for.

One other thing to remember...

When climb nobody says you have to ride in a straight line. I never do. I always switchback unless the traffic is that heavy and the shoulder is that narrow. The switchback is designed to decrease the grade of the road, use the same concept to your advantage to make it up the road easier in a bigger gear.

Back in 2012 before my first bike trip I rode up a 2000+ foot climb, averaging 12% with an extended 18% grade stretch. I rode the 3.7 miles in under 40 minutes and did it in a 36x25. Yes, I pretty much stood the entire climb and since it was a park road I pretty much had the entire road to myself so I used the entire road switchbacking my way up the road.

Gears on a bike will never replace smarts in the brain...never. The gears just make it harder because you don't know how to ride the bicycle correctly in the first place.

Jim Kukula

Looking at Bike Calculator - say the total weight is 225 pounds (it is for me) and I am climbing a 12% grade at 5 mph... that's about 300 watts!

Makes perfect sense... my standard hill in my neighborhood is about 12% and I go up at about 2.5 mph which is then 150 watts. Yeah 150 watts gets me tired but that's something I can sustain for ten minutes or whatever... with a cool breeze, anyway!

BigAura

The Blue Ridge Parkway itself is graded quite well but the roads on and off it can be steep. 21" is fine for the Parkway but I'd go the 16 if you're going on the access and fire roads a good bit, especially in the NC area.

BTW: I did the entire Parkway with a low of 42" (90lbs of bike&gear), when I was very fit 27yo. No pushing while I was on the Parkway.

DropBarFan

Blue Ridge Parkway is a beautiful ride but all up & down. Not super-steep but climbs can be very long. I'd go w/Bike A.

Tourist in MSN

On my derailleur touring bikes, my lowest gear is 24 chainring and 32 on the rear. The cheapest first move would be a smaller chainring. I assume you need a 74mm BCD chainring, they are not very expensive.

Someday you will need a new chain and cassette, you could get that bigger cassette now. And since a bigger cassette may need a couple more links, get a new chain with it. When your trip is over, switch back to your old chain and cassette until you wear them out. But, I would just start with the chainring and see what you think of your gearing after that.

GetUpnGo

This is exactly the reasoning I used to set up my gears. It corresponds to a typical mountain bike set up:
Front: 22-32-44
Rear: 11-34

22 front and 34 rear will give you 17". I use that gear constantly on hills (unloaded hybrid, paved roads).

I find that if 17" isn't low enough, it's better in terms of energy and control to get off and walk.