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Old 04-14-12, 08:57 AM   #1
garethzbarker
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How is your pocket rocket geared?

I just ordered a custom PR. I ended up just getting the stock gearing. Even though I would have liked a lower low end I found it hard with normal components to get get really low and yet stay high enough.

What kind of gearing do you have on your pocket rockets? the stock for 2012 is a capreo cassette 9-26 and an FSA triple 30/42/52. Is it possible to run a smaller small chainring without messing up the shifting? Is anyone running higher end 10 speed?
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Old 04-14-12, 09:23 AM   #2
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the 30t chainring can be exchanged for a smaller .. I use a 26t instead.
[Though the 52,42,26, is not on a a BF,PR bike, and the crankset not FSA]

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Old 04-14-12, 09:27 AM   #3
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the 30t chainring can be exchanged for a smaller .. I use a 26t instead.
[Though it's the 52,42,26, not on a a BF,PR bike]
I was wondering about that. no shifting problems?
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Old 04-14-12, 09:34 AM   #4
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Big, upshift, from the granny to the middle , I don't try to force it while still climbing the slope.

Read the terrain, anticipate the gear range you need.

go from middle to, 3rd ring and a middle gear on the cassette,
then down from there with the rear shifter, as the slope rises more.

It's better than Bogging down on a climb, in too high a gear.

speaking a s a touring rider , not a racer..

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Old 04-14-12, 10:03 AM   #5
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I just ordered a custom PR. I ended up just getting the stock gearing. Even though I would have liked a lower low end I found it hard with normal components to get get really low and yet stay high enough.

What kind of gearing do you have on your pocket rockets? the stock for 2012 is a capreo cassette 9-26 and an FSA triple 30/42/52. Is it possible to run a smaller small chainring without messing up the shifting? Is anyone running higher end 10 speed?
How low of a gear do you need? A 30/26 combination with a 20" wheel is pretty low. Sheldon's website calculates 23" with a 28-451.
How high of a gear do you need?

I'd be inclined to customize a cassette with a 30t cog. Your bike and derailer can almost certainly handle it and it would lower your gearing about 10%.

I swapped out the 30t granny for a 26t granny for a ride with a 3-mile long 12% grade on the NWT. It shifted OK without a chain stopper or other thingy to prevent the chain falling off the inside. Although my middle chainring has 39 teeth.

http://www.youtube.com/watch?v=pgpzQTmsiYQ
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Old 04-14-12, 10:38 AM   #6
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You're right, it's not high. It's actually pretty low but I'd like to extend the low end for future touring. if I did my math right I'll have 23 to 115 gear inches on the PR. My Surly is perfect for me with a low end of 19. A 26t cog would get me almost the same low end as my surly I think. a 24 would get me lower. Is it hard to do? Just count the bolts and buy a chainring with the same number or is it more complicated than that?
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Old 04-14-12, 12:29 PM   #7
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You're right, it's not high. It's actually pretty low but I'd like to extend the low end for future touring. if I did my math right I'll have 23 to 115 gear inches on the PR. My Surly is perfect for me with a low end of 19. A 26t cog would get me almost the same low end as my surly I think. a 24 would get me lower. Is it hard to do? Just count the bolts and buy a chainring with the same number or is it more complicated than that?
Swapping the two is very easy.

I'm pretty sure that your crank is BCD 130/74. 26t chainrings are cheap and plenty. Just make sure you get BCD 74 chainring. You can always check with the manufacturer of your crank.

I'd only swap the granny when you're touring since the shifting will be worse with the 26t granny; although it will still be acceptable, IMO. I think a 24-tooth chainring would result in very sketchy shifting with STI.
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Old 04-14-12, 01:18 PM   #8
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G, you might be able to get a second wheel with a bigger cassette. Whether or not that works with your current RD remains to be seen, though. I tried an 11-32 in place of the 11-28 for an attempt at MTBing on my BF and the Tiagra Medium cage didn`t like it. I wasn`t interrested enough to use a different derailler.

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I'd only swap the granny when you're touring since the shifting will be worse with the 26t granny; although it will still be acceptable, IMO. I think a 24-tooth chainring would result in very sketchy shifting with STI.
Could that likely be done without moving and adjusting the derailler each time? I guess as long as the big ring stays the same, you could dink with it just once (or maybe not even that) to work with both setups, then swap away whenever. I`ve never tried a similar thing, though- I have terrible luck getting front deraillers to work right, so usually try like the dickens to avoid messing with them.
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Old 04-14-12, 01:34 PM   #9
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My bike is a 1994 and I wouldn't gear new one this way but the following has worked well for me for the 15 years it has been on the bike. Front is a double with a 46 inner and a 60 outer chain rings. The rear is a standard Shimano 11 to 28 8 speed cassette. Roger
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Old 04-14-12, 06:36 PM   #10
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I may need to swap to an MTB rear meck also right? To avoid chain wrap problems.

Wow rhenning, is that what came stock back then? I know they make big chainrings but I've never seen where to buy them and wondered how you figure out how much your Front mech can handle.
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Old 04-14-12, 09:22 PM   #11
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I also run a 60t chainring on my 20"/406 Moulton TSR-20 ... in my case, it's a 20 speed .. 60/39 up front and 11/28 in the back.. Vuelta has large chainrings in 130bcd usually in stock up to 60t.. I use bar end shifters and an Ultegra road F/D and a mid-cage R/D ..
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Old 04-14-12, 11:32 PM   #12
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fietsbob I understand. My surly trucker shifts kind of like that. it's dependable and has a wide range but the shifting isn't smooth. You get used to it after a while.
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Old 04-15-12, 01:48 AM   #13
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My Bike Friday PL I went with Rohloff's hub ..

the 52,42,26 is on a 70's made frame with over the BB cable guides.
it was a FD bottom edge clearance issue.
when I had a under the BB guide, I got the 50,40, 24.
and an older Campag MTB [80's] FD .

friction shifting is smooth for me , with 40 years of using it, on various bikes..

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Old 04-15-12, 04:41 AM   #14
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I also run a 60t chainring on my 20"/406 Moulton TSR-20 ... in my case, it's a 20 speed .. 60/39 up front and 11/28 in the back.. Vuelta has large chainrings in 130bcd usually in stock up to 60t.. I use bar end shifters and an Ultegra road F/D and a mid-cage R/D ..
This makes a lot of sense. what's your gear inch range? for more range one might be able to use an 11-32 and XT rear mech.

I plan on keeping it nine speed for the capreo. If I upgrade components I'll use high end MTB stuff, a nice road crank and barend shifters probably. But barends aren't my favorite. I love the weight and their sturdy nature but I hate reaching down every time I want to shift.
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Old 04-15-12, 05:29 AM   #15
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I also run a 60t chainring on my 20"/406 Moulton TSR-20 ... in my case, it's a 20 speed .. 60/39 up front and 11/28 in the back.. Vuelta has large chainrings in 130bcd usually in stock up to 60t.. I use bar end shifters and an Ultegra road F/D and a mid-cage R/D ..
I have a very similar setup - 11-32T cassette, 60T+42T chainwheels, XT shifters and RD, Ultegra FD. I couldn't go smaller than 42T as the chain drags on the FD cage with a 39T chainwheel. I had to use a spacer between the braze-on and the FD to get it far enough backwards to match the chainwheel profile. The shifting works quite well, considering the chainwheel does not have chain pickup pins or profiles. I have a similar setup with Dura Ace barend shifters on the Swift.
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Old 04-15-12, 07:42 AM   #16
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On mine it came stock with a 42-52 front and a 13-28 rear which made me run out of top end very quickly. With the big sprockets my high gear is 109 gear inches and my low is 33 gear inches. The original top gear was only 80 gear inches. The derailluers on the bike are standard Shimano Ultergra/600s. My Bike Friday had a factory spacer like JUR did for his . My front derailluer is a braze on by the way. Roger

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Old 04-15-12, 09:08 AM   #17
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Mine is a '93 that came with 60/50 in front and 11-28 in back. I replaced the 50 with a 42 to get a wider range and I've found it to be adequate for my touring although my low is still not as low as the OP's. The old 50t 'small' ring has since been put into service as the new large ring on my Cannondale after the original 52t ring wore out.
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Old 04-15-12, 09:17 AM   #18
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I noted on BiFri, store, spare Caprio cassettes are about $85, ouch !.
and you can use no other.
https://www.bikefriday.com/thestore/...eZ7-2&cPath=11
hope you can find them, for replacement spares, cheaper in Seoul, or HK,
nearer the Mfg. source.
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Old 04-15-12, 09:19 AM   #19
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This makes a lot of sense. what's your gear inch range? for more range one might be able to use an 11-32 and XT rear mech.
Gear inch range is approximately 26 to 101 .. that covers most everything I do... I don't spend much time pedaling over 30mph, so the lowish top end doesn't bother me and my typical cruise speed lets me run the 60t at about the middle of the cassette, so chainline is good and it runs quiet.

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I plan on keeping it nine speed for the capreo. If I upgrade components I'll use high end MTB stuff, a nice road crank and barend shifters probably. But barends aren't my favorite. I love the weight and their sturdy nature but I hate reaching down every time I want to shift.
Bar ends work good for me because I run various trekking bars.. the Soma 3 speed bars or VO Porteur bar have proven comfortable with their shallow drop and natural hand position.

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Old 04-15-12, 11:07 AM   #20
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Could that likely be done without moving and adjusting the derailler each time? I guess as long as the big ring stays the same, you could dink with it just once (or maybe not even that) to work with both setups, then swap away whenever. I`ve never tried a similar thing, though- I have terrible luck getting front deraillers to work right, so usually try like the dickens to avoid messing with them.
I never touched the front derailer when I did the swap. And yes, the position is determined by the big chainring which remained the same.
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Old 04-15-12, 11:09 AM   #21
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I also run a 60t chainring on my 20"/406 Moulton TSR-20 ... in my case, it's a 20 speed .. 60/39 up front and 11/28 in the back.. Vuelta has large chainrings in 130bcd usually in stock up to 60t.. I use bar end shifters and an Ultegra road F/D and a mid-cage R/D ..
Supposedly, packing a bike with super large chainrings is an issue. If I remember correctly, they complained about the chainrings being very close to the edge of the suitcase.
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Old 04-15-12, 11:14 AM   #22
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I may need to swap to an MTB rear meck also right? To avoid chain wrap problems.
Are you referencing a triple with the 26t granny?

Since I never cross chain, no I had no need to swap in a super long derailer (SGS). So if you're willing to give up riding in a granny and small cogs -- say anything below the 13 -- and your chain length is set correctly, you'll almost certainly be fine with a road triple (GS) derailer.
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Old 04-15-12, 11:19 AM   #23
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G, you might be able to get a second wheel with a bigger cassette. Whether or not that works with your current RD remains to be seen, though. I tried an 11-32 in place of the 11-28 for an attempt at MTBing on my BF and the Tiagra Medium cage didn`t like it. I wasn`t interrested enough to use a different derailler.
I fit a cassette with a 30t cog on my NWT and 105 triple (GS) derailer. I can't remember whether I adjusted the b-screw a bit.

I decided to use the 26 tooth granny over (1) taking apart/combining a capreo and 9-speed Shimano cassette or (2) using a 11-30 cassette since I wanted the top end for the century ride.
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Old 04-15-12, 11:51 AM   #24
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I'm going to try the stock configuration when it gets here. if it's not low enough I may try this: http://www.chainreactioncycles.com/M...?ModelID=23102
Lighter and cheaper than ultegra and provides a 19-106 range in gear inches. That's more than my touring bike. on the high and the low. the 22/32/44 MTB cranks aren't bad either.
It's really a shame they don't make more 9tooth options.
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Old 04-15-12, 01:37 PM   #25
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I'm going to try the stock configuration when it gets here. if it's not low enough I may try this: http://www.chainreactioncycles.com/M...?ModelID=23102
Lighter and cheaper than ultegra and provides a 19-106 range in gear inches. That's more than my touring bike. on the high and the low. the 22/32/44 MTB cranks aren't bad either.
It's really a shame they don't make more 9tooth options.
You might have issues getting the front derailer low enough for the big chainring. I'm pretty close to the bottom of the braze-on mount with a 50t chainring.
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