[cwg_at_opc]

i want to change my 1991 D/A 53/39 crank to an FSA SLK compact.
my daily ride is about 20 miles of easy rolling terrain and a decent hill
(if anyone knows griffith park in the burbank/glendale area, i go up the
hill behind traveltown, but not all the way up to the helipad); i'm doing it
to save my knees since i'm not getting any younger. i don't race, so it's
mostly fast fitness riding. i try to keep my cadence up near 80 when i
can(per rocco's advice) but when we hit the hill(either side) i'm maxxed-out
at 39x23 pushing maybe 40-45 when i'd rather be spinning in the 60s-70s.

are there any pitfalls i should be aware of? i know that i'll have to fiddle
with the front derailleur, any other tricks/tips?

current setup:
1991 kestrel 200ems(54)
1991 DuraAce 8spd SIS 53/39x12-23
2005 supergo korso/michelin pro2race(23)

 

[nitrotech]

Unfortunately you have a bit working against you. The SLK compact crankset is designed around 10 speed drivetrains. If your using 8 speed, the chain may rub on the outer chainring (50t) when in the small (34t) Also your front deraillur may not be able to handle the tooth capacity (16t) between gears. You may experience missed shifts and neutralling (where the chain rides on top of the teeth instead of engaging it).
If you can use a 9 speed chain on your system, that will help and you may need a new front deraillur. Unfortunately there might be an element of experimentation. I suggest if you get the crank, try it with your current setup. You may get lucky and have perfect shifting right away. if it doesn't work change the front deraillur and chain if you can. Another inexpensive change would be switching the 34t to a 36t. That will decrease the tooth spread and could potentially reduce the chain rubbing when in the smaller chainring. Hope that helps.

 

[VaughnA]

Before changing out the Front D try setting it up a little higher than recommended. This is a tip from FSA. I've done it on two compact equipped bikes and they shifted much better than when it was setup with the normal 5mm clearance over the big ring. On my bike I just didn't move the fd when I installed the compact. My wife and I both have fsa compacts and they shift fine without the special compact fd.

 

[cwg_at_opc]

thanks guys, that's about what i expected, i was also thinking about the 36t
ring - the 34t might be a tad _too_ small. when i searched the forums earlier
i saw that suggestion for moving the fd UP.

while i am saving up for a completely new ride, i do need to save my knees
right now. the new bike will probably also have a compact crank. maybe
zipp will make a compact version of their new unit.

 

[Keeping up with Junior]

Here's a Tip

...1991 DuraAce 8spd SIS 53/39x12-23...

Here's a Tip. Buy a cassette with cogs that are suited to your terrain and riding style. The trick is to buy a cassette rather than get suckered into the marketing hype that a compact crank is the only way to get more appropriate gearing. A new cassette will be a far cheaper solution for you.

 

[VaughnA]

OOOPS I agree with Junior...

Here's a Tip. Buy a cassette with cogs that are suited to your terrain and riding style. The trick is to buy a cassette rather than get suckered into the marketing hype that a compact crank is the only way to get more appropriate gearing. A new cassette will be a far cheaper solution for you.

I was just giving a compact tip and missed that he was using a 11/23. Even though I run a compact I agree that he's got a lot of room to just go with a 12/27 in this case. That will give you a lot more low end than he has now. Easy and cheap.

As for me, I'm about 185 (Lost 7 in the last month woohoo!) and ride quite a few steep rides including some of the east-coast challenges. That's the main reason for a compact in my case. I do a lot better on the really steep sections with the compact. But for my normal riding I can easily get by with a standard double.

 

[terry b]

Before you do anything, plot the ratios of the gears you use now against the gears that a compact will provide. You might find thatyour preferred range forces you into some oddball locations on the cassette and it might eliminate your ability to use the small chainring at all for your type of riding.

I did a compact on one bike and it caused all kinds of interesting problems. Chain rub on the inside of the 50 when in the smallest 3 cogs. Severe undergearing on the small ring to the point where it was useless for anything but the hardest climbs. Running almost exclusively in the big ring but only in the range of the biggest 4 cogs. Weird stuff that rendered the bike a pain in the neck for my regular (mostly flat, some hills, occasional steep climb) riding. To get that bike back to useful, it took a BB spacer, a 38 small ring and a 48 big ring. Now, it's mostly useful for my style and I can swap the 38 for a 36 if I'm riding somewhere with big climbs.

Simply put, I don't think compacts map well to all riding styles and I also don't think they're a magic solution.

 

[alienator]

Before you do anything, plot the ratios of the gears you use now against the gears that a compact will provide. You might find thatyour preferred range forces you into some oddball locations on the cassette and it might eliminate your ability to use the small chainring at all for your type of riding.

I did a compact on one bike and it caused all kinds of interesting problems. Chain rub on the inside of the 50 when in the smallest 3 cogs. Severe undergearing on the small ring to the point where it was useless for anything but the hardest climbs. Running almost exclusively in the big ring but only in the range of the biggest 4 cogs. Weird stuff that rendered the bike a pain in the neck for my regular (mostly flat, some hills, occasional steep climb) riding. To get that bike back to useful, it took a BB spacer, a 38 small ring and a 48 big ring. Now, it's mostly useful for my style and I can swap the 38 for a 36 if I'm riding somewhere with big climbs.

Simply put, I don't think compacts map well to all riding styles and I also don't think they're a magic solution.

What TerryB said. Plot your current gearing and the gearing you think you might like. It's the gear ratios that will have the solution.

That said, I think your pedaling at the low end of the cadence range. If you've got sore knees, you'll want to pick up your cadence, say to 90 or better, on the flats. For moi, 95-105ish is my flat ground comfy spot, and on climbs it's no worse than 80's. Keep in mind, you may not be able to jump immediately to a new cadence regime. It takes some time to adjust.

 

[cwg_at_opc]

What TerryB said. Plot your current gearing and the gearing you think you might like. It's the gear ratios that will have the solution.

That said, I think your pedaling at the low end of the cadence range. If you've got sore knees, you'll want to pick up your cadence, say to 90 or better, on the flats. For moi, 95-105ish is my flat ground comfy spot, and on climbs it's no worse than 80's. Keep in mind, you may not be able to jump immediately to a new cadence regime. It takes some time to adjust.

95-105: yikes! i knew i was spinning at the low end, but i personally find anything
over 95 to be too fast. a cadence between 75 and at most 90 is comfortable
right now. perhaps as i ride more i can kick it up a bit. as a returning rider,
i am finding that my old riding style was based on sheer leg strength, which
i don't have anymore - so i have to spin more and mash less.

as for gearing, according to sheldon brown, i can customise my own
cassette, which is what i assume you guys are suggesting. what i can't
find is how big a cog i can use with the old D/A RD - it looks sort of like 27
is the max without going to a long-cage. obviously, i'd prefer to save my
moolah for the new ride, so if i can snatch a few cogs from one of my old
MTBs and use them, then that's all the better...

 

[alienator]

95-105: yikes! i knew i was spinning at the low end, but i personally find anything
over 95 to be too fast. a cadence between 75 and at most 90 is comfortable
right now. perhaps as i ride more i can kick it up a bit. as a returning rider,
i am finding that my old riding style was based on sheer leg strength, which
i don't have anymore - so i have to spin more and mash less.

as for gearing, according to sheldon brown, i can customise my own
cassette, which is what i assume you guys are suggesting. what i can't
find is how big a cog i can use with the old D/A RD - it looks sort of like 27
is the max without going to a long-cage. obviously, i'd prefer to save my
moolah for the new ride, so if i can snatch a few cogs from one of my old
MTBs and use them, then that's all the better...

Well, that's my cadence range. Iffin' I were you, I would try to get it up to 90ish. It makes a big difference on sore joints. After breaking my hip, as soon as I could get back on the bike I found that climbing....lower cadence.....did not please my as yet to be completely healed hip, but a higher cadence was no problem. Sure that's an extreme example, but if someone's got sore knees, then those knees are moving that person closer to the extreme example. To have lower gearing available is the key, since that reduces the load on sensitive body bits.

Using a gear ratio or developed gear ratio spreadsheet or calculator doesn't mean just futzing with cog gearing. You can also play with chainring options. If you're on a non-compact crank, you can fit a 38 tooth chainring up front. Granted, that won't cause a huge ratio change, but it will make some difference. In the big chainring, you can fit down to a 46 tooth with Shimano and 50 tooth with Campy. And if you want to sample compact, you don't have to use a 50/34.

I played with my own spreadsheet quite a bit before settling on what my new cranks would have. Currently I've got 53/39 up front and 12-25 in back. After all the spreadsheet futzing, I've settled on 50/36 front and 12-25 in the back. Granted the difference between that combo and a 53/39 with a 12-27 isn't great, but the 50/36 is just that much more optimal for me, my cadence, and where I ride (not a lot of flats, lots of hills, rolling hills, and mountains). I figured since I was changing cranksets I'd make things as right as possible.

The nice thing about a spreadsheet calculation is you can look at all of the different ratio possibilites side by side and see where the differences are. Whatever you decide, don't feel like you have to be married to any popular set of ratios. You have to decide what's going to be best for you.

 

[cwg_at_opc]

i've dug out a spare MTB wheel that has a 7speed 13-30 cluster
that looks like it has a 26t cog next to the 30t, so when i find my
hyperglide cluster key and chain whip, i'll try it out.

i did mess around with sheldon brown's java gear calculator thingy
and i think you guys are right about not bothering with the compact
crank right now. on the other hand, sugino and salsa make 38t inner
rings, so if i have to they're available...

 

[ARP]

Saving money?

FSA SLK? How much? Nashbar has their house brand compact crank for around $80? Of course you would need a new BB. Made by FSA. Also I ride a FSA Energy crank, sort of economical <$150. If i had to do it over again i probably will go with a Ritchey compact. Has the 36/50t and a really nice looking crank. Lastly, check the classifieds here for a deal on a compact, lots of people jumped on the Tyler bandwagon and found out it wasn't "their bag of weed".

 

[ericm979]

According to Sheldon Brown you can run up to a 30t cog on a shimano road derailleur. I've run a 28t with no problem. You might check out Sheldon's custom cassettes. You could even build your own with a 26t or 27t solo cog, replacing the 12t and 13t with a 13t small cog. You'd lose a bit off the high end but a 53x12 isn't useful very often for most riders. Sheldon Brown sells individual cogs. As long as you have a steel freehub body (some fancy expensive wheels have aluminum freehub bodies) the individual cogs work great.

 

[cwg_at_opc]

FSA SLK? How much? Nashbar has their house brand compact crank for around $80? Of course you would need a new BB. Made by FSA. Also I ride a FSA Energy crank, sort of economical <$150. If i had to do it over again i probably will go with a Ritchey compact. Has the 36/50t and a really nice looking crank. Lastly, check the classifieds here for a deal on a compact, lots of people jumped on the Tyler bandwagon and found out it wasn't "their bag of weed".

i found the SLK compact for $267 at fullcycles.com. i chose that model because
of the integrated megaexo BB(supposed to be better than ISIS) and yes, i think
i would have preferred a 50/36 over the 50/34. looks aren't as critical to me at this
point, though nicer looking for me is the new zipp crank(which isn't a compact)

According to Sheldon Brown you can run up to a 30t cog on a shimano road derailleur. I've run a 28t with no problem. You might check out Sheldon's custom cassettes. You could even build your own with a 26t or 27t solo cog, replacing the 12t and 13t with a 13t small cog. You'd lose a bit off the high end but a 53x12 isn't useful very often for most riders. Sheldon Brown sells individual cogs. As long as you have a steel freehub body (some fancy expensive wheels have aluminum freehub bodies) the individual cogs work great.

i'm going to try to replace the 23 with a 26 and maybe a couple of others to smooth
out the jumps, but i want a bail-out gear for those days when the hills are looking
a bit grim. the cassette i'll be taking the cogs from isn't being used anymore.
hopefully the freehub body on the Korso won't give me any troubles.

 

[alienator]

i'm going to try to replace the 23 with a 26 and maybe a couple of others to smooth out the jumps, but i want a bail-out gear for those days when the hills are looking a bit grim. the cassette i'll be taking the cogs from isn't being used anymore.
hopefully the freehub body on the Korso won't give me any troubles.

Sounds like a good plan. For the fun of it, you oughta try a 38 on the front little ring. Your chosen plan is good, though, as you can try some things at low cost. Little pain for good knowledge.

As to the Zipp Crank.....yeah, it looks pretty good. Not as good as the Claviculas I'm waiting on, but still good. I dunno why they didn't bring out a compact, too.

 

[cwg_at_opc]

Sounds like a good plan. For the fun of it, you oughta try a 38 on the front little ring. Your chosen plan is good, though, as you can try some things at low cost. Little pain for good knowledge.

As to the Zipp Crank.....yeah, it looks pretty good. Not as good as the Claviculas I'm waiting on, but still good. I dunno why they didn't bring out a compact, too.

thanks, i'm a cheap [email protected], so low cost works for me every time. ;-)
Heh. found the hyperglide key and whip. now, where's my monkey wrench?

c

 

[cwg_at_opc]

hey! 38/50 at 130bcd

Hey everybody, thank you all for your comments and suggestions,
it has been entirely too cool to learn and discover things from
you guys.

so, a little more researching shows that i can in fact get the gearing
i was thinking about _without_ changing my entire crankset...

bikeman has Salsa 38 and 50 rings at 130bcd($24.95 and $30.95)
wdbike has FSA rings(38t for 20.47 and 50t for 30.13)
with shipping, i'm looking at about 60-65 bucks, not too terrible.

does anyone have any other places they like to shop at?

oh, and silly me, the xt cassette i was going to use has nearly
the entire cluster pinned together, so no easy 26t cog for me yet.
i've gotta go to a couple of my LBSs to see what they've got
laying around.

Thanks again everyone! if you think of anything, drop me a line!

 

[alienator]

Hey everybody, thank you all for your comments and suggestions,
it has been entirely too cool to learn and discover things from
you guys.

so, a little more researching shows that i can in fact get the gearing
i was thinking about _without_ changing my entire crankset...

bikeman has Salsa 38 and 50 rings at 130bcd($24.95 and $30.95)
wdbike has FSA rings(38t for 20.47 and 50t for 30.13)
with shipping, i'm looking at about 60-65 bucks, not too terrible.

does anyone have any other places they like to shop at?

oh, and silly me, the xt cassette i was going to use has nearly
the entire cluster pinned together, so no easy 26t cog for me yet.
i've gotta go to a couple of my LBSs to see what they've got
laying around.

Thanks again everyone! if you think of anything, drop me a line!

Chances are that you can grind the heads off those pins and pull the cassette apart. Someone that knows Shimano cassettes better could prolly say for sure.