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#1
I picked up a low end Cannondale Hybrid (1999 H300) to get back into cycling and to learn a few things about bike mechanics. The bike is great for fitness, but I've started to tear it apart and refit with some inexpensive upgrades, as that is the stuff I love to do. My latest project has been to replace the BB (110-68 square taper-JIS) and upgrade he crank. The original spec listed the crankset as a C.P.I, but once I pulled it I found it to be a 175mm Shimano FC-M290 and it had been the subject of a recall in the late 1990s, so I'm glad I'm doing this upgrade.

The original crank was a 24/34/42 which I plan to replace with a 30/42/52 FSA Vero crankset. Here is where my problem lies. The new FSA crankset slides in too close to the frame. Upon closer inspection I have come to realize the not all crankset BB shafts are created equal. The original Shimano crankset BB shaft extends beyond the innermost chain ring by about 1/8" inch...an "outie", so to speak. The FSA chainring BB shaft is recessed, an "innie", and therefore slides too close to the frame. So I have learned that cranks come as "innies" and "outies".

Can anyone recommend a reasonable triple crank that will fit my "outie" needs. I'd like the largest ring to be in the neighborhood 48-52 teeth. When I look at pictures of cranks, it is really not possible to determine the BB shaft length on the inside. I'm sure there is a more technical description, I'm just not sure what it is.

Thanks to all who have taken the time to read my lengthy post. Any advice will be greatly appreciated.

Bill
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#2
Hello Bill, it would be great if you could get some pics to post. more info would be nice also like what shifters you have and derailleur models. You are talking an extreme mod to from a 42t to a 53t chainring. Most people could never spin a ring like that to actually go faster. Your problems may only be beginning with your question because I pretty sure you will be out of range with the tooth capacity of your front derailleur too.
What rear cluster do you have tooth wise?
There are two kinds of people in the world, "Those who help themselves to people, and those who help people!"
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#3
Photo 
Thanks for responding!

You are right for sure about the extreme mod and the FSA Vero crank is not going to fit anyway due to it coming too close to the frame. So I'm probably going to be purchasing a crank with a 48t max ring. The shifters are SRAM Gripshift MRX Comp Shifters. The front derailleur is a Shimano FD-M290. The rear cassette is a Shimano HG41 11-28t. Like I said this is all low end, more of a learning project than anything.

Here's pic of the original crank that shows the BB shaft protruding past the innermost ring. I had to use some brute force to remove the old crank as the threads were stripped, so there is not a lot left of it, but you should be able to see what I'm talking about. The shaft extends approximately 1/8" beyond the chainring.

[Image: FC-M290.jpg]

Any advice on a replacement triple ring crank in the neighborhood of 48t max would be greatly appreciated.

Bill
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#4
for the money this is a good start
http://www.ebay.com/itm/Shimano-48-x-38-x-28-Triple-Crankset-FC-M361-175mm-Black-Acera-Bicycle-Cranks-/332305018209?epid=1000057395&hash=item4d5eec2d61:g:AEoAAOSw5AFZaUQn

match with the correct size bottom bracket something like this
http://www.ebay.com/itm/Shimano-UN-55-Sealed-Square-Taper-Bottom-Bracket-68x122-/301278229249?hash=item462594f301:g:sK8AAMXQhpdRykbK

alloy cups vs the lower end plastic cup.

Now decide on what chain you will want. I would go with one that uses a quik link vs a shimano chain that uses a pin. Better for the novice and quik links work well and make for removal and cleaning easier.

Understand that the Bottom bracket length is determined by the crankset being used. Not by what is in the bike at the moment. If it happens to be 122 or 123mm and is in good shape then you can still use it for the crankset i had linked too. if not it has to be replaced with the proper size to fit the new crank.
There are two kinds of people in the world, "Those who help themselves to people, and those who help people!"
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#5
Thanks for the advice. I've moved ahead with the crank and BB you recommended. I really appreciate your help.

Bill
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#6
let us know how it turns out. Back in 1996 I bought my Daughter a silkpath 300 with the delta frame and headshock. She still has it to this day. Nice looking bike.
There are two kinds of people in the world, "Those who help themselves to people, and those who help people!"
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