fz77

Hey. Time to replace my crankset. Truvativ 5D 48/38/28 on a 2014 REI Novara Buzz

​​​​​​Only problem is I can't find a replacement anywhere. I found a 170-mm crankset online but nobody has the 5D 170-mm arm in stock.

The 175-mm arm isn't too hard to find but there again...I can't find a matching crankset.

I assume there are some restrictions in swapping out for a totally new brand (eg, Shimano), but what are my options? And if I do that will I have to replace other parts (chain, derailleur etc) to accommodate the new crankset?

Thanks in advance

Iride01 

They are square taper JIS to the spindle. So just get any other square taper JIS that suits your fancy and is appropriate for that bike. REI might have some suggestions if you bought the bike from them.

If you want to open your selection of cranksets, then consider replacing the BB too. Most BB's are less than 18.00 USD. Some less than 10.00 USD.

I'm on the older side of 50 and when I went to longer cranks on a couple of occasions I had some very minor issues I just didn't want to put up with. So if you are older and have been using 170's for a long time, then take that into consideration. Though my experience might not be typical.

3Roch

are you replacing it because you hate it or cuz it's worn out? I have aTruvative Touro triple crankset that has about 50 miles on it, 170 arms, that is excess to my needs (took off a recumbent I bought.) It's 30/42/52 so might want a slightly longer chain but if your crank s shot the chain needs to be replaced anyway

Send me a PM if you might be interested for more info

edit: now I'm confused...When I looked at 5D crank arms the picts were JIS/square (which is what the Touro is. When I later looked at the 2014 REI Buzz info it said it had a 5D crank with a splined BB ?!. It might help the thread to know if yours is square BB or splined.

dedhed

More importantly that is designed for the spindle length of the current BB

Iride01 

Yep, I quit using square tapers long ago. Too much to consider. Even the fact that some are JIS and there were other square taper standards back in the day made for complications.

tyrion

I'd replace the crank with a Shimano Hollowtech II crank and BB because parts are easier to find. I think a 3x9 crank will work fine on your 3x8 system. Lots of those on ebay. You can often find Deore 3x9 cranks (48-36-26) new for less than $100 and BBs for $25.

But maybe you just need new chainrings?

fz77

Thanks for the suggestions.

3Roch: Nah those cranks have been good to me. Just time to replace 'em.. Yes my BB is a spline. Arms on my bike do not have the square sockets.

Tyrion: replacing the Truvativ with a Shimano means I would have to swap out some of the other parts I already have, is that right?
What kind of chain would I be using on a 3 * 9? 8 or 9 speed?
What about my SRAM derailleur? Would I have to swap that out for a Shimano as well?

Thanks for all the help

Iride01 

Durn..... so much for googling. All the pic's showed a square taper as did several on eBay I looked at. Still same advice though.
Octalink and ISIS are two different types of splined spindles. Still will limit your choice of cranks if you only look for what fits that bb spindle.

dedhed

Just replace the chainrings

fz77

Maybe my last post wasn't clear enough. My understanding is that the parts are inter-related. I'm hesitant to make a major swap because I don't want to get halfway through a repair only to realize the existing parts aren't compatible.

Can I ask what the rationale is for "just replacing the chainrings?"

dedhed

They are interrelated. The crankset and BB shell type/width/threading/pressfit determine what BB length or type is needed.

Unless damaged about the only part on a crankset that wears out is chainrings. What is it besides that makes you say, "Time to replace my crankset"?

fz77

It looks like the arms and chainrings are sold together as a unit... And the bottom bracket is part of the whole. If one part is worn I'd rather just replace the whole mechanism.

dedhed

https://www.servicearchive.sram.com/..._spc_rev_a.pdf

sweeks

I'm going to be a bit hyperbolic here, but this is like saying:
"My car's tires are worn out, so I'm getting a new car."
Removing and replacing chainrings is a snap compared to replacing the crankset.

fz77

That makes sense...but it still takes me back to square one: the parts aren't in stock anywhere

tyrion

A new crankset and bottom bracket is all you need.

https://www.ebay.com/itm/Shimano-Ali...sAAOSwL0xe4kn9

Or, as I said, maybe just new chainrings.