quadripper

Hi,
I have a 14spd road bike with 52/42 130mm chainrings. I have noticed that I could use higher and lower gears-
If I upgrade to a 53T/39T chainring set (still 130mm), will I notice much difference? I don't really want to replace shifters or the cassette and I found a 53T/39T raceface chainring set for $30 on nashbar.

Also, It says it is compatible with 9/10spd drivetrains. Will it work with my 7spd? What is the difference between that and my 7spd drivetrain? I can't find any chainrings that are 7spd compatible.

Thanks for your help.

bikemig 

yes they will work with your 7 speed. To determine whether it will make much of a difference, take a look at online gearing calculator. That's a good deal for 2 chainrings. I think a 39 tooth helps with climbing over a 42 tooth; I'm skeptical that a 53 tooth will make a big difference over 52 tooth though.

FBinNY 

52 to 53t is a 2 percent difference and will barely be noticeable. 42-39t is about a 7% difference, which is probably equal to slightly more than half the difference between your two lowest gears. Not exactly day and night, but if your rings are worn anyway, and you only need some room at the ends, it might make sense given the low cost.

If you need more range, note that dropping a tooth on the high end is usually about 8% difference. At the other end of the range every added tooth to a typical low gear is roughly a 4% difference (assumes a typical 13-26 cassette as a guide since you didn't specify).

If you need seriously lower gearing, consider buying a triple crank, but that may entail a new FD also.

fietsbob

thinner teeth of 10,11 "speed" chainrings are fine with the wider 7 speed chains..

its all 0.5" standard between roller centers of the pins.

TallRider

another option if you want notably lower gearing is a "compact double" setup. You'd need to get a different crank (typically with 50/34 chainrings) and you could stick with the derailers you currently have.

Al1943

You could, of course replace the 42 with a 39 on your old crankset. A 53 is a waste of money compared to a 52. I would have a slight preference for the 52 for closer ratios, especially with a 39 inner ring.

quadripper

I couldn't find a 32T chainring that would fit a 130mm BCD crank

FastJake

That's because the smallest ring that will fit on a 130mm crank is a 38T. I think Al must have made a typo in his post.

I'd look for a 38 rather than a 39, which should be a noticeable difference compared to your 42. Then keep your 52. But as others have said, if you need seriously lower gearing you need to look into a compact or triple crank. What cassette/freewheel are you using?

DOS

I have 52/42 on one of my bikes. As others have said, the difference going to 53 would make is not worth the trouble. I do notice the difference between 42 and the 39 I have other bikes but its not huge. If you haven't already maxed out your rear freewheel/casette -- I am guessing freewheel since a 52/42 set up is kind of old school so am thinking we are talking about an older road bike -- you could go as big as 27 or 28 tooth large cog and, paired with a 39, generate a more noticeable change on the low end.

quadripper

My cassette is a 14T/28T shimano 7-speed.
I'm basically trying to see how i can increase my gear range without replacing my derailers/shifters.

All my daily, during-the-week riding is flat. But on the weekends I like to go into the hills, and I have noticed that both a lower low gear and higher high gear would be helpful on some of the steeper grades. I may be able to justify the expense of a new triple crankset or something. I'm just not there yet.

quadripper

I guess switching to a 12T/32T 7-speed cassette would make a bigger difference?
Is it pretty easy to replace the Cassette?

FBinNY 

I see your problem, but you're up against the limits of the hardware without spending some dough. If the RD can take it, you might look for a 13 or 12-30 freewheel which would expand the range and combine it with a 38t chainring (leave the 52 alone). The smaller high gear sprockets will raise the high effectively, and the combined chainring reduction and larger rear will help at the low end.

However, spreading the range of 7s freewheels spreads the gear separation in the mid range, and can be worse on flat and near flat terrain where you do most of your riding. Setting up gearing means balancing close spacing, and wide range, which is why bikes are now 10s and 11s (20 & 22) and or triple, which lets you eat your cake and still have some for later.

FastJake

You can try a 38T ring but frankly it sounds like your best bet is a triple. Clearly more expensive (you'll need the crank, probably a new FD, possibly a new RD and possibly shifters unless you have downtube shifters.)

Replacing the cassette is easy, but with a 14-28 make sure it's not a freewheel first.

FBinNY 

+1, a 7s 14-28 smells like a freewheel. Also make sure the RD has enough capacity for a 32t.

Often,when one starts a gear change project it takes on a life of it's own, as in "there was an old woman who swallowed a fly....."

So do all your research, and decide where your headed before spending dime one.

Al1943

Sorry, that was a typo. The smallest possible chainring on a 130 crankset is a 38.

bikemig 

There are all kinds of trade-offs here but the most straightforward is a triple with 7 in the back. A bigger freewheel or cassette means you lose a lot of in between gears that are useful. A compact would help out a lot but you probably want one with only a 10 tooth jump with 7 on the back. A cross compact (46-36) would help out but you want to keep a 52; so bite the bullet and get a triple.

sedges

Sounds like the RD limits a cassette above 28, so the lowest double crankset you can find will extend your low end. They don't have to be expensive. A less-than $50 crankset will serve you fine. The 50x34s are nice to help your climbing. An example:

https://www.niagaracycle.com/categori...e-taper-silver

You can extend your high end, or at least get it back with the drop from 52 to 50 in front, by replacing the 14X28 cassette with an 11X28. Again, this does not have to be expensive. Example:

https://www.niagaracycle.com/categori...1-28t-cassette

I personally don't worry about the high end. Learning to spin more efficiently takes care of a lot of that. But then I also have been known to coast when I get beyond my high gear. I understand that others wish to press for speed at all times. Extending the low end, however, makes a HUGE difference for climbing.

Totoboa

Very Very true. You will feel a three-tooth difference.

FBinNY 

So the OP has a sense of the difference, going from 42 to 39 will have an effect equal to slightly less half the difference he gets changing from the 24 to 28 on his existing bike, it would be comparable in effect to having a 30t instead of the 28 on his existing freewheel. So if the 28 is only marginally too high, and he only needs a bit more it makes sense. If he needs more than that, like another full step or two lower, he's wasting the money because he'll be back looking for a triple or compact drive in very short order.

Here's a link to a very nice gear chart, so the OP can see the possibilities at a glance.

tcarl

+2 re: 7 speed 14x28 sounds like a freewheel. Check that.

quadripper

FBinNY thanks for your help in this thread. I have learned what I needed.

fietsbob

50-34 cranks would be a better climbing double 50/14 is a 95" high, low about 33"