mrveloman

The tour I'm planning on this summer will be across the southeast - Atlanta, Georgia - Alabama - Mississippi - to SW Louisiana so no mountains but maybe some shorter steep hills in the first half. Also I am going to motel it as I will be time limited and will not want to camp in the heat. So hopefully a light load - I am planning on only using my Ortleib Front Rollers (mounted on the back) and expect I'll have maybe 12-15 lbs if I take my laptop.

Therefore, I think am going the easy route and sticking with a road crank - no need to replace the BB or FD. I am now looking at a 24-36-48 Sugino XD2 for $137 incl shipping. Not as low as I think I will eventually need but should work for now. However I am still open to suggestions.

Mike

fietsbob

The Sugino chainrings are pretty low cost IF you have a 110-74 crank, (which you never said) 34 is the smallest middle 24 the smallest 3rd

Road The 130 bcd can be no smaller than 38t..

mrveloman

My existing crank is 74 bcd and 130 bcd. I looked into chainrings for it and it would cost $65 for a 24, 38, and 48 chainrings.

mike

djb

perhaps I missed a step, but why not just spend $65 and get the same stuff as the $137 Sugino? I recall you mentioned something being stripped but I really wasnt sure what threads got stripped (I assume you mean the threads of the crank that you use the puller/pusher doohickey to get the crank off the axle?)

Doug64

David, you are absolutely correct on this. It is a long story, but Shimano used to make FM-442 and FM-443 cranksets; one used a 45 mm chainline, and one a 50 mm chainline. Both used the same chainrings. We had 2 bikes with the 45 mm chain line setup, and I wanted to change the 45 mm chainline cranks from a 48/36/26 (OE) to the 44/32/22 configuration. They have Octalink bottom brackets so shorter BB was not an option. However, I could buy the entire 50 mm chainline crankset with the rings I wanted at a price significantly lower than the individual rings.

mrveloman

Well I ordered the chainrings today - $64 for 24-38-48 for my old crank. Hopefully I can let you know how it works out in a week or two.

Mike

Tourist in MSN

Since your biggest will be a 48 instead of a 52, you can probably shorten the chain slightly. I mentioned above in post number 8 that I have a 52/42/24, I find that I can't use the 24t chainring when I am on the 11 or 12t cogs on the cassette because the derailleur will not take up all the slack. (Those gears are pretty cross chained so I would not use them, even if I could.) The reason that I mention this is that you might find that you also can't use a couple gears when you are on the 24t in the front but if you take a link or two out of the chain, that may help.

If you find you are dropping chains when you downshift to the 24t chainring, get a chain catcher. I have one on my bike (photo in post number 8 above) and I have no idea if it does any good, but I never drop a chain.

djb

about chain length, I really do recommend doing a google search (or go to the Park Tools site, its great) on how to properly measure your chain, its always always prudent to have the length right so that if for whatever weird reason, you shift into big-big, and so you dont put your rd into your wheel is the chain is too short. I figure that a chain that may rub up against the derailleur in a small -small situation will only make a little noise to tell you not to do this--but this is better than if ever you or someone else rides your bike and goes into the big-big, which could ruin the derailleur, the wheel......mucho dinero.

look it up, its pretty straight forward how to check chain length for a given set of gears--it aint rocket science.

oh, and I agree that those chain catcher doohickies work wonderfully. Ihave this one on my bike and Im sure there are lots of others out there in the same price range.

https://www.chainreactioncycles.com/c...-/rp-prod84217

mrveloman

It is definitely no fun to have a chain that is too short. Sheldon Brown has some good info with pictures on getting the correct chain length: Derailer Adjustment

Hopefully I won't need a chain catcher though I do have one my tandem.

mike

nfmisso

I would like to suggest an alternate: keep your current cranks, and build up a custom cassette with a 15 or 16T little cog and a 36T big cog. The bigger cogs result in less tension in your chain and lower force on the teeth of the cogs for any given gear ratio and power/torque output of the rear wheel. Result, longer chain, cassette and chain ring life. Downside is a few extra ounces.

djb

I'll chime in, not sure what you mean by "less tension in the chain" but the lower force on the teeth comment--there most likely is a diff but I suspect its only on paper, ie meaning in real life the diff is negligible. I do know that I can feel how a 12t feels "rougher" than a 13 or 14 or whatever, and 11t feel clearly rough to me (chain is binding more due to the smaller circumfrance I guess) but I would say that one usually doesnt stay in the 11 or 12 that long. I hardly ever stay in the 11 (down hills for a short time) and even the 12 doesnt get used that much by me.
Having used a 7 speed 13-30 for many years, I would add that having a 15 or 16 smallest cog would be rather frustrating. On my bike with a 42/32/22, I spend a lot of time in the 32 and I dont like spending extended time in the 12t, so shift up to the 42 ring and downshift a gear or two, that said, I do use the 14, 16 alot. On my old bike with a 50/40/24 with the 13-30, the 50/13 spins out at around 30mph which is a bit frustrating, and in the 40 ring, I used to regularly use the 17, 15 and 13, so again a 15 or 16 small cog would be limiting and frustrating in real life.

your idea seems to me thats its more on paper, and not really applicable in the real world--not meant to be a slight but I figure the fact that you dont see folks using a cassette like you suggest shows that it isnt something that is worth doing---also, using a 36t cassette could very well mean a new rd, so that cost plus the cost of a custom cassette (if you didnt do it yourself, and if you did, you'd have to have donor cassettes to mix it together)

mrveloman

So I received my new chainrings the other day and installed them on my old crank. I now have a very nice low gear. The shifting is a little rough going from the small to middle ring which I suspect is the result of using my old FD (which I did have to lower by about 1/4 inch). I may think about swapping it for a mountain bike FD. I ended up have to remove only one link from the chain (based on Sheldon Brown method of wrapping around the big ring/big cog with a one link overlap). I didn't check how slack it is on my small ring/small cog because I only use the four or five largest cogs with the small ring. I will be riding the bike more in the next few weeks to see how well I like the new gearing.

Thanks to all for your advice and comments. It was indeed quite helpful.

mike

djb

enjoy

mrveloman

Rode 45 miles yesterday and 27 today (in the rain) and was quite happy with my new gearing. I stayed mostly in the middle and large rings but did attempt an 18% hill in my small ring. Shifting seems to work well now after a few tweaks still using my original Ultegra 6503 front derailleur. I'm not entirely sure if my 24-32 low gear will be low enough for me to tour in my current physical condition but hopefully that will improve over time.

Thanks again

mike

djb

Re hills. It's completely normal when at the beginning of season to feel like you do. Just keep on putting in the hours riding, even short rides but do return to the hills because you will get a bit stronger each week with regular riding, it just takes time. I find by mid to late summer I'm climbing the same hill in 1 of 2 gears higher and the effort is easier, it ain't magic, you just have to put in the hours in the seat.
Keep at it and you'll soon notice an improvement.