Anyone know? Thanks in advance.

68mm.

Thanks. Do you know the axle length by any chance? I'm looking for the correct BB to use with a sugino 75 crank.

i just ordered a dura ace bb and set of dura ace cranks for my pista concept and the required axel length was in the crank specs

I know this is noob question but, if I want to get new sugino rd messenger crankset do I need to get a new BB, this is for a 08 bianchi pista also.

The axle length is based on the crank you're using. Just use the Sugino BB to make life easy.

the truvativ cranks use a powerspline (i.e., not square tapered BB), so you need a new BB that works with whatever cranks you want to use.

Yep, just realized that =(. Any suggestions on the best priced BB to match the 75's to ensure a proper chainline? I think the Pistas rear hub is 42mm but i'm not too sure. The 75's suggest using anything from a 109-110mm BB.

I was looking into order that as well, but I figure you'd have the same problem with the non square tapered BB. The matching RD BB is pretty cheap though, but the combo apparently gives a 45mm chainline which some people have apparently found problematic so I decided it would be best to go for the better cranks anyway. Hopefully somebody else more knowledgable can help out.

My cranks came pretty scratched up so I might just see about trying to buff out some of the scratches first, so I suppose that will end up being the first thing to go.

If you don't want the more expensive Sugino BB then you can use a Miche Primato Pista BB in the 110 size. The BB is around $25 and has adjustable cups. It is ISO taper and will work fine. Otherwise if you want to spend a bit more any of the Campy 111mm ISO BB's will work. They can be found for $35-45 online. Both of these BB's are sealed and will work fine for street us. The Sugino 75 BB is great but can become damage if not cleaned well from time to time as it is unsealed. It is designed for track use. I can be used on the street, many people use it on the street, but unless you plan on a regimented service schedule, I would go with one of the cartridge styles that are sealed.

Look at Business Cycles online for the 110mm English Miche Primato Pista BB. Don't buy the 107 by mistake! This will give you 42mm spot on with the adjustable cups. AND it is Cheap which is what you are asking for.....

What a quick and helpful response! Thank you so much, looks like i'm all set.

In terms of the RD Cranksset. Many people run the chainring on the inside of the spider to shave a few mm and get closer to the 42mm chainline. Tons of info on these subject thru the search function. Don't look as good this way, but it will make for a straighter chainline.

I know at least 10 people running the Miche BB with Sugino 75 cranks. You get what you pay for. Works fine and is a good value for the money. Is it as nice as the matching Sugino 75 BB or a Phil Wood BB? Well, NO! But it is cheap and will do the job. Can I assume you are using this bike on the street?

Yes, I'm using is solely for the street as a commuter, so the Miche BB sounds like it would suit me well.

Just have to add up the combined costs to see if it's possible right atm. Gonna need a new 42t chainring as well.

If you don't mind me saying so..... running 75's on a commuter is going to be some costly overkill. If you are doing this to end up with "Real" track cranks with 144 BCD then that is your business.

As a note, if you are looking to get into real track cranks most of the quality track chainrings start at 46T and up. A rider on the track would have no real use for a 42T ring. If you look you will see that the 42T chainrings are almost 100% resigned for used with 130 BCD cranksets.

The only one I can think of that is 144 BCD and comes in a 42T is Sugino's Zen Messenger ring. Their are a few 43 and 44's out there but the choice of a 42 is quite limited.

What size cog are you running? If you are starting from scratch you may want to get a more standard track chainrings size that is still cool for the street (like a 46-48T) and then get a cog that is more suited to the gear ratio you want to ride.

Oh, are we talking 1/8 drivetrain? On Bianchi's site for the 08 Pista is doesn't state if the crainring or the cog are 1/8 or 3/32 size but the chain listed (KMC Z610H) is only a 3/32 chain according to KMC's Website so, one can assume that the stock cog and cr on the bike are only 3/32 as well.

So, if you go with the 75's you have one choice for a 42T, 1/8 chainring, and have to get a new cog anyway and a new 1/8 chain on top of the crank arms and new bottom bracket. In effect you are replacing 100% of your drive train! If you are gonna do that, move away from 42T and find another CR to Cog combo that gives you the gear inches you want to ride.

Look at Sheldon Brown's thoughts on gear ratios online, it will be very helpful.

Thanks again, you've been more than helpful.

Would there be a problem with going with the messenger chainring for now, buying a 16t cog and then switching the chainring later? The reason I ask is because I do plan on moving up to LA within a few months where it's less hilly and there will be access to some tracks.

*Sorry for edit

You can get totally decent and ridable stuff in 130BCD and it will be fine for a commuter. If you are the kind of guy who if he's going to upgrade wants to upgrade once and only once then I would say buy the 75's and the Miche 110mm BB and the 42T CR and 16T Cog. Look at it as an investment. If you think you might not be into bikes in a few years I would say to save your money. Bottom line is you get what you pay for and if you want 75's get them. You may want to look at the newer Miche Primato Pista 144 BCD cranksets too. Little less and they come with a chainrings (probably not a 42, but you could buy it with a 46, keep it for after your move) and then throw the Sugino 42 on it for now.

The Zen Messenger rings are nice, not the best, but still a very good chainring. You don't need a $90+ ultra round chainring for a commuter.

Ben Cycle has a lot of the parts we've been talking about and has GOOD photos so take a look if you don't know about them yet

https://www.benscycle.net/index.php?m...65be9fb8b4eac6

Why would you want to spend all this money upgrading an already decent set of TruVativ cranks? It'd be less hassle, and a wiser use of the cash to spend your money on a decent set of wheels.
I'm guessing as it's an 08 Pista the bike is pretty much new, you could wait until the chainring/sprocket/bb starts wearing out, then upgrade to the 75.
I just got a set of TruVativ Omnium's for 08 Pista and once the rest of my bike arrives I look forward to testing them out. Overkill for street use? definitely.

Yep. I just performed this switch on my '08 Pista and I used an IRD QB-55 JIS square taper bb 68x103mm. The Truvativ Power Spline BB that comes stock is 68x108mm and is ISIS so it must be replaced to use Sugino RD's. I think Sugino makes a 68x103mm square taper as well.