kenshireen

I have a KG96 with that standard for that era 53/39.
I am looking for a compact crankset so I can get some smaller rings on the front.

My bike is 600ex and I would like a similar quality component..
The problem is I cannot find a crankset that can accommodate a 7 sp cassette.
All the more recent 50/34 have larger cassette capacity of 9/10/11 etc.

Any suggestions or any workaround to get something smaller on the front.
I currently have a campy chorus and want to switch out to Shimano.

If I cannot get this done I will have to look for another bike to handle the hills.
53/39 doesn't do it for me.

thank you

aggiegrads

I would go with something like the venerable Sugino XD. Comes std with 36-46, and replacing the middle ring is not expensive. Should have as good or better quality than what you have.

Change the BB to 110mm, and have a ball.

If you want a low Q, and a higher quality, go with the forged 7075 Velo Orange Rando. 30/46 should give you the range that you need. 5-10 speed compatible.

Drew Eckhardt 

Buy a 9/10/11 crankset which suits your tastes and move the small ring to match your existing crank's spacing.

Wheels Manufacturing, Origin8, and LeTour all make 0.6mm chain ring spacers. 1mm and thicker spacers are common.

andr0id

Please explain why you think this won't work again?

The chain line for a double has not changed.

A FC-5800 can be had in a silver anodized finish and would work fine.

Andrew R Stewart 

+1 here. Andy.

Brian25

Relax, You have it backwards. The new 8,9 or 10 crank chain rings are closer together because the new chains are narrower and if you run a 8,9or 10peed chain on an older crank the chain can jam between the rings when you are in the big ring/ small cog and shift to the small ring. If you have an older (wider) 7 speed chain, it will work perfectly fine with an 8,9 or 10 speed crank.

joejack951

You can always run a narrow chain, too.

Drew Eckhardt 

The gap isn't big enough to jam a chain, although you might get skate shifting to the small ring. Running a 9 speed chain on an 8 speed crank worked flawlessly for me.

A 9 speed chain won't work perfectly fine with a 10 speed crank in all situations.

When I tried a FSA "9 and 10 speed compatible" Carbon Pro Compact 50/34 crankset with a Campagnolo 9 speed chain and 40.6cm chain stays I had no usable overlapping gears due to big-ring rub in the last 2-3 cogs.

Spacing it back to actual 9 speed dimensions fixed the problem.

Drew Eckhardt 

The rings are closer together which causes the wider chain to rub on the big ring in a few smaller cogs.

That's a bigger problem with compact canksets (wide range spread between rings), tighter cassettes (narrow total range), and fewer cogs in back all of which can combine to produce no silent overlapping gears between rings or too few leading to excess front derailleur shifting.

You could run a narrower chain, although that's more expensive, may slow rear shifting, and some people find it cuts life.

Fortunately spacers are an inexpensive one-time fix.

HillRider

A viable alternative is to buy a 9 or 10-speed crank and use a 10-speed chain with the 7-speed cassette. I'm running a 10-speed Tiagra crank and 10-speed Shimano chain with an 8-speed cassette and rear shifter and it works perfectly. The front derailleur may need to be updated but they are cheap.

rccardr 

There are a ton of EX era Sugino 110 cranksets out there and you might even be able to use your existing BB. Also a lot of Deore stuff out there that's 110/74, just take off the inner ring. SR Apex, too, but the rings are odd sized and not as easy to find.

You might have to change one (or both) rings, but modern rings on an older crankset do not require spacers. At least they haven't on the several I've done this with. Strip the anodizing with oven cleaner (use rubber gloves and an SOS pad), then polish with 600-800-1000 grit and Mothers. Wax to keep it from corroding.

kenshireen

I spoke to a bike mechanic at Nashbar and asked why the compact cranksets that I looked at referenced 10 or 11 speed cassettes. He said that the spacing would not work on a 7 speed
and also the chain would need to be narrower.

kenshireen

Wouldn't I also have to replace the chain? How would I measure the existing crank spacing

kenshireen

Let me make sure I understand.... I have a 53/39 with a 7 speed cassette... Are you saying I can buy a shimano 50/34 and not be concerned about anything else and just switch out the crankset. Can I run an 11 or only 8,9, 10

Drew Eckhardt 

You can buy whatever crankset you want for 8 or more cogs (9, 10, 11, Tiso 12 speed). Measure the new crank ring spacing with calipers, subtract the measured spacing on your 7 speed crank, buy spacers adding up to about that thickness where a little more won't hurt, install spacers between spider and small ring, and use longer chain nuts (perhaps from your 7 speed crank) if the ones included in the crank fail to engage the big ring.

HillRider

The spacing on 10/11-speed cranks won't work with a 7-speed width chain but a 10-speed chain works fine with a 7-speed cassette.

Drew Eckhardt 

No. The point of the exercise is to convert the new crank to 7 speeds so you can use 7 speed chains which cost less, may last longer, and should shift better with the wider spacing on 7 cog cassettes.

Between teeth (outside faces, inside faces, the same face) in a consistent manner directly or derived (measure spider thickness, chainring tooth offset on both rings, and add them).

Use a caliper (digital, dial, or vernier; Chinese ones are inexpensive), height gauge and granite table, or whatever is most convenient. Longer calipers often have jaws with more reach.

In theory you could add spacers until rub just goes away, although that will take longer.

Brian25

Some minimum wage kid answering the phone at Nashbar is not any sort of an authority. I probably have been doing this far before he was even born. Even being a head mechanic at a PBS store over 25 years ago.

andr0id

Even with an "11 speed" crank.

I have a 6800 crank loose at the moment. I can put a chain I pulled off only bike with a 6 speed freewheel on it and I can even fit an 1/8" chain on the small ring and it fits without hitting or rubbing the big chain ring.

Yeah, you might get some chain rub against the big ring if you cross chain from the small ring to the smaller cogs. Don't do that.

I check an older FC-7400 and the rings are 7mm apart center to center. The FC-6800 is about .5mm narrower with the rings being 6.5mm apart center to center.

You'll get that with short chain stays even with all matching components. Just a cost of running a 50/34.

kenshireen

[QUOTE=andr0id;18525031]Even with an "11 speed" crank.



Yeah, you might get some chain rub against the big ring if you cross chain from the small ring to the smaller cogs. Don't do that.

How do you get chain rub against the big chain if going small to small... the small ring is inside the large so it doesn't have to pass over the large?

kenshireen

Hillrider states that you cannot use a 7 speed chain with a 10/11 speed crankset.
Drew states that you can use the chain but you will need spacers?

Isn't this conflicting information....

Homebrew01

Not conflicting. You could combine the information into 1 sentence:

"you cannot use a 7 speed chain with a 10/11 speed crankset unless you use spacers"

andr0id

[QUOTE=kenshireen;18525191]It's an angle thing. Put you bike in the small chain ring and the small cog on the back and you'll see it is very close to touching the inside of the big chain ring out near the teeth. Usually it just misses, but sometimes it will drag a tiny bit. My 6650 compact crank would rub in the 2 small cogs. It's just makes a bit of noise, doesn't hurt anything.

fietsbob

Nashbar is a shipping warehouse not a Bike shop , you conversed to someone there to take your Order.

facilitate sales of what they stock ..

Performance bike Inc. is the company that runs a few retail shops and its own warehouse retail shipper,
they bought out their competitor, Nashbar, so own them too.

The 600ex is old parts , you win auctions on eBay to get that ..

fietsbob

Get one of these ROAD CRANKS ? White Industries VBC allows you to even have an inner chain ring

smaller than 34t, because the bolt circle is slots not a set of holes ..

Premium quality, made in California. USA....


BITD, Merckx climbed the Pyrenees & Alps with a crank that only went down to 42t & Rd Maxing at 26 or 28t



maybe you need a triple crank .. Thats my choice on my touring and road bikes that dont have an IGH.