Converting to a Compact Crank

[Peter P.]

I'm thinking of converting my Shimano Ultegra 6500 9 speed setup to a compact crank. Currently it's a 39x48 with bar ends.

If I understand correctly, I can interchange a 10 speed crank with 9 speed.

I'd have to replace the well worn chain and cassette, but the costs would be minimal.

Problem is, there are few if no Ultegra level 10 speed compact cranks on the market.

So that means change everything to 11 speed, just to get compact gearing.

Then I look on the internet and seems due to the pandemic bike boom, no one has complete 11 speed groups.

Some questions: If I convert to 11 speed, would I have to get a new rear hub to accommodate the 9-11 speed upgrade?

Can I just buy a 10 speed crank if I can find one and be good to go?

More questions may follow. Thanks!

[AngryScientist]

you can use an 11-sp crank with your 9-sp drivetrain, no problem.

in fact, my friction shift 9-speed bike uses a 12-speed campagnolo crank with perfect shifting.

you should easily be able to source a 6800 or R8000 crank and be good to go.

[oldpotatoe]

I'm thinking of converting my Shimano Ultegra 6500 9 speed setup to a compact crank. Currently it's a 39x48 with bar ends.

1)If I understand correctly, I can interchange a 10 speed crank with 9 speed.

I'd have to replace the well worn chain and cassette, but the costs would be minimal.

2)Problem is, there are few if no Ultegra level 10 speed compact cranks on the market.

3)So that means change everything to 11 speed, just to get compact gearing.

Then I look on the internet and seems due to the pandemic bike boom, no one has complete 11 speed groups.

4)Some questions: If I convert to 11 speed, would I have to get a new rear hub to accommodate the 9-11 speed upgrade?

5)Can I just buy a 10 speed crank if I can find one and be good to go?

More questions may follow. Thanks!

1)..yes

2) and 3)..They are out there, yes, tough to find BUT you needn't 'change everything' with a 11s crank. You may get some chain to big ring 'tickle' when in small ring and smallish cogs but don't go there. Barend-front der..easy..plug and play with crank.

4), yes, probably..maybe a freehub body swap, depends on your wheel..if shimano-nope, new rear hub.

5)..yup..and it needn't be 'Ultegra'..any compact would work fine, even horrors, Campagnolo

[pjbaz]

If you must go 11s on a non-11s Shimano hub it IS possible to use an 11-32 (or 34, I forget offhand) 11s cassette.

At least, it works on my DA 7850s (thanks to hte interwebs) :banana:

[rccardr]

I'd suggest looking for a nice Sugino TD series crankset. Works fine with 9-10 speed Shimano components and with a 110 BCD will get you down to a 34 inner.

Have those on several bikes including the Bianchi seen below.

[pjbaz]

I'd suggest looking for a nice Sugino TD series crankset. Works fine with 9-10 speed Shimano components and with a 110 BCD will get you down to a 34 inner.

Have those on several bikes including the Bianchi seen below.

That's a good looking crank, and bike.

[cmbicycles]

If Shimano crank, you are looking for R700 crank that will match the 9s the best... there is a 175mm ln the bay for $50 at the moment. https://www.ebay.com/itm/293699381249

6750 was the 2nd gen 10s compact crank, but wont match the aesthetics of 9s as well. Lots of other companies with compact crank designs as well, you will need to get a different BB in many cases, but would need to do that for the Shimano 10s as well.

[Look585]

Shimano R700 and R600 for the best match, but hard to find.
The Tiagra 4650 is a really nice crank as well and the logos come off very quickly with a rag+acetone. Chainrings are not fantastic but are standard 110bcd so easily upgraded.
Sugino XD is also a nice option in square taper.
IRD Defiant is very nice in square taper.

All of these would fit aesthetically much better than a "modern" crank.

[Spaghetti Legs]

Here are my compact setups right now, all work great with exception of rare chain suck in the IRD.

Velo Orange cranks (Labeled I think as 10 speed) on one Centaur 10 speed Ergp and another 6 speed Campy friction.

IRD Defiant on Campy Record 8. Boulder Bike has these, last I checked for $165, which is the best price I’ve seen around.

Athena 11 speed on Record 10

I bought a gorgeous Sugino XD from Bens Bikes for $200 shipped but haven’t decided which bike to use it on yet, probably another Campy 8. When I was shopping for the Sugino, in normal times you can get it direct for Sugino from Japan, with BB, shipped and insured for about $200. Now, however, they have to use a different shipper which pushed the cost higher.

In your situation, barring an easily sourced Shimano crank, I would go with one of the above (except maybe the Athena) and use a 10 speed chain. The Sugino would look nice with Shimano group.

@rccardr - that Bianchi sure would look nice in Celeste ;)

[zzy]

+1 for an r700 or r600. Newer Sora cranks work great too.

[steelbikerider]

That's my crank in the ebay link above. PM me if you are interested.

[Peter P.]

you can use an 11-sp crank with your 9-sp drivetrain, no problem.

in fact, my friction shift 9-speed bike uses a 12-speed campagnolo crank with perfect shifting.

you should easily be able to source a 6800 or R8000 crank and be good to go.

That's good to know. Jumping to 11 speed right away will mean I won't have to upgrade a 10 speed crank when the other parts need replacement.



2) and 3)..They are out there, yes, tough to find BUT you need'nt 'change everything' with a 11s crank. You may get some chain to big ring 'tickle' when in small ring and smallish cogs but don't go there. Barend-front der..easy..plug and play with crank.

Thanks for the heads-up on the chain noise. I forgot the wide chainring spread would cause that. Dutifully forewarned.

I'd suggest looking for a nice Sugino TD series crankset. Works fine with 9-10 speed Shimano components and with a 110 BCD will get you down to a 34 inner.

Have those on several bikes including the Bianchi seen below.

I love the crank AND the bike. Setup is perfect, and the fork curve is well, curvaceous! I think Peter White Cycles sells the Sugino stuff. I'll have to look into it.

Follow up questions: If I convert the crank to 10 or 11 speed, do I need to change the front derailleur (remember; I'm using bar ends)?

If the crank goes to 10 or 11 speed, does the chain follow suit, or do I stay with a 9 speed chain to match the cassette?

[oldpotatoe]

Peter P asks
Follow up questions[/B]: If I convert the crank to 10 or 11 speed, do I need to change the front derailleur (remember; I'm using bar ends)?

If the crank goes to 10 or 11 speed, does the chain follow suit, or do I stay with a 9 speed chain to match the cassette?
[/QUOTE]

No need to change the front der and match the chain to the cogset, not the crank..

[ridethecliche]

10 speed crank should work fine with 11 speed afaik.

[smead]

You should be able to find a sugino or ritchey Octalink compact crank for your 6500 BB. If not, no reason to even consider 11 stuff as 10 speed compact crank and BB combos are aplenty and very cheap these days (because everyone's gone Nigel Tufnel to 11). Oh and most are silver which will match the rest of your 6500 bits.

[Peter P.]

Thanks again for the replies.

Yet more questions:

If I were to convert to a compact, 34x50 and retain my 12x27 cassette, I would have to get a rear derailleur with more chain wrap capacity than my short cage RD6500, right?

Thanks for the Ritchey crank suggestion; that's really doable for me and I like Ritchey products.
Ooops-looks like Ritchey has stopped marketing cranksets.

[Mark McM]

If I were to convert to a compact, 34x50 and retain my 12x27 cassette, I would have to get a rear derailleur with more chain wrap capacity than my short cage RD6500, right?

Maybe. A 50x34 + 12x27 requires a chain wrap (derailleur capacity) of 31 teeth. A Shimano RD-6500 SS (short cage) derailleur has an official capacity of 29 teeth (see: https://si.shimano.com/pdfs/si/SI-53Z0D-000-00-ENG.pdf). But official capacity specs. are often conservative, so with proper chain length sizing, this derailleur might be able to handle it. If it were me, I'd try it out with the current derailleur first.

[smead]

Thanks again for the replies.

Yet more questions:

If I were to convert to a compact, 34x50 and retain my 12x27 cassette, I would have to get a rear derailleur with more chain wrap capacity than my short cage RD6500, right?

Thanks for the Ritchey crank suggestion; that's really doable for me and I like Ritchey products.
Ooops-looks like Ritchey has stopped marketing cranksets.

Unless you avoid running big-big / little-little you might need a long cage 6500 or 7700 or 7800 short short might work. 6700 RD in gray/silver is pretty long in a short cage.

Search the classifieds here, I've seen ritchey compact cranks come up. You should be able to find ritchey or sugino on Ebay, might take a bit of time to get exactly what you want in the proper crank arm length. Note the ritchey WCS cranks were prone to cracking on the NDS. I ran a ritchey pro crank for a couple of years and eventually cracked the NDS.

[ridethecliche]

I wouldn't hesitate to get a modern compact crank and test things out with your current setup and see how it works on the stand first.

Also with a compact you might not need to cross chain that hard.

[Road Fan]

I'm thinking of converting my Shimano Ultegra 6500 9 speed setup to a compact crank. Currently it's a 39x48 with bar ends.

If I understand correctly, I can interchange a 10 speed crank with 9 speed.

I'd have to replace the well worn chain and cassette, but the costs would be minimal.

Problem is, there are few if no Ultegra level 10 speed compact cranks on the market.

So that means change everything to 11 speed, just to get compact gearing.

Then I look on the internet and seems due to the pandemic bike boom, no one has complete 11 speed groups.

Some questions: If I convert to 11 speed, would I have to get a new rear hub to accommodate the 9-11 speed upgrade?

Can I just buy a 10 speed crank if I can find one and be good to go?

More questions may follow. Thanks!

I would start by changing the chainrings on my existing crank and riding it for a while to see if the basic ideas of the 16 ish tooth chainring skip works for you. If it feels good on the road, you can go ahead and figure out the more ideal situation - how many cogs, brifter/Ergopower, et cetera. With your 8/9sp you are using Your existing chainset is 39/48 a 9-tooth jump. The norm for a road compact is 16 teeth. Campy and FSA have designed crank arms for 50/34. I don't know if Shimano has arms that can get you there. But some folks looking to upgrade have had trouble with the shifting. I didn't so I can't analyze it but I'm convinced it is worth checking befor eyou go in for a big ticket conversion.

I think FSA is worth looking at. They have a range of models of chainset, all with similar Star Wars styling, for better or worse. You would have to look at the BB interface designs.

I suspect your small chainring is as small as your arm can accommodate. If you can fit a 36 or 34 ring onto it instead of your 39 then I gotta think a 52 tooth spare ring is not an expensive item, and chances are it does not need to be Shimano.

[Peter P.]

I finally completed my conversion from 9 speed standard crank to 11 speed compact crank. I thought I'd give a report as my thanks for all the advice.

I converted from a 12x27, 39x48T setup to an 11x28, 34x46T crank. I got a lower-low, and a higher-high gear (I wasn't aiming for that!)

I initially bought a 34-50T crank but even before installing it I knew the 50 was too large for me, and I can't stand big shifts in the front. I ordered a 46T ring and paid a whopping >$150 for the privilege! To top it off, it's not a direct replacement; the 46 requires special chainring bolts (ordered separately, after the discovery) to continue with that flowing crankarm look, and just to fit the rings. Front shifts are still not as good as the 9T difference I'd come to love. I don't know how some of you tolerate 34x50 or 39x53!

I was planning to run bar end shifters and was concerned about having to frequently trim the front derailleur. With STI it's not much of an inconvenience, and with 9 speed bar ends and much longer chainstays on my other bike no trimming was ever required. I didn't think it would be a problem so I ordered the 11 speed front derailleur.

I was wrong and I should have trusted the suggestions here and re-used the 9 speed front derailleur. The shorter chainstays on this bike along with 2 more cogs meant semi-regular trimming of the front derailleur. The ridiculous front derailleur routing, cable tension adjuster, and that silly little cap to retain the cable pigtail were bitter icing on the cake. I was ready to live with it but I still had the 9 speed front derailleur on hand so I reinstalled it. I measured the cage width and it's definitely wider by +1mm in key points.

On the workstand the 9 speed front derailleur works like a charm; no dropped chain and chain rub is limited to the last cog on each end of the cassette. I expect it will work fine on the road.

As to the ergonomics on the controls, I will say I've no doubt STI is more convenient and more comfortable. My brake levers lack the girth of STI levers and thus the comfort. I wanted bar ends partially because I have them on my commuter and always liked the interactive nature of reaching for them. I never had to look at the cassette to see what gear I was in; I could feel the lever position and knew instinctively where I was. And I wanted to brag that bar ends have a friction option, in case something goes south and I need the switch. Alas, friction shifting has been eliminated on 11 speed.

I also wanted separate levers because with the 9 speed setup and my handlebar shape, i had to lower the levers on the curve to reach them easily while in the drops. That was equivalent to a lower handlebar, while on the hoods, and I wanted to "raise" my bars. With separate levers (the same bar/lever setup as on my commuter) the levers were moved up solving both issues.

The separate brake levers changed the mechanical advantage of the brakes. Compared to the matching STI calipers/levers, these Shimano levers shift the balance toward power and away from modulation, maybe 10%. This combination is a touch less forgiving with hard braking. Shimano says they're compatible with all their dual pivot brakes, but I suspect it's only true of older vintage brakes.

If I had to do it again, I'd go STI. Nevertheless, I can say I'm happy. I've got my lower gears, minimal front trimming, and the interactive nature. I've always marched to the beat of a different drummer, so the mysterious outlier coolness of bar ends is just a bonus!

Thanks for the advice.