daotan

Helping a buddy rebuild his 20 year old Nishiki. We are both novices at bike-wrenching. Question: is there a special tool that we are supposed to use to remove the cranks? The 15mm socket I have does not fit into the well where the nut lives. See 1st pic.

2nd pic shows the plastic cover that was originally covering the hole. We managed to break it trying to remove it. Its gonna be a PITA to try and get that out.

Last question: do I need to remove the cranks to remove the bottom bracket?

Thanks in advance.

moxfyre

Yeah, sometimes it's a 14mm socket, although generally a 15mm. It looks like corrosion may be what is preventing the tool from fitting in there, but a little hard to see.

And yes, you must remove the cranks to remove the BB. You will need an old-style BB lockring wrench, or you can use an old, junky screwdriver as a punch. And you'll need something for the fixed cup too, I believe a large adjustable wrench will work on this if it is like other Nishikis of similar vintage. You should replace the BB with a modern cartridge model... only $15 to $25 and superior in nearly all respects, especially not needing regular maintenance.

I have overhauled a Nishiki Sport which had the same cranks in excellent condition. They are nice cranks, just polish off that surface rust and you'll like their look!

PS- You're supposed to use a coin or screwdriver to unscrew those plastic covers for the crank bolts :-P

JanMM

Remnants of the dust cover should come out with knife, needle nose pliers, whatever.

HillRider

Most of the Japanese bolted cranks I'm familiar with (SR, Sun Tour, Shimano and, I think, Suguino) use a 14 mm socket.

Remove the dust cover remnants with what ever it takes but don't damage the crank arm threads. I've even softened plastic ones with a soldering iron to get the pieces out.

Yes, you must pull off the crank arms to remove the bottom bracket.

daotan

i'll try a 14mm, yes i tried the soldering iron trick, thanks everyone for the great info

i've got a set of Shimano 600 Ultegas that i want to use, better than the Suginos no? there definitely newer and in better condition

kevbo

The appropriate crank puller tool has (had?) a socket incorporated into the head of the "bolt" part. The puller/dustcap treads and taper of the cranks are the same as modern BBs. This is the only crank puller I own. I have to install a socket-head cap screw when pulling modern cranks, as the nose of the pusher bolt doesn't reach the BB shaft, and might bugger up the hole if it did.

JanMM

Ultegra isn't necessarily better than Sugino, SR, etc. Looks are important, though.

HillRider

Ultegra cranks will have enhanced chainrings (shifting ramps, pins, etc.) that older SRs and Suguinos won't and they make a very noticable difference in shift speed and quality even if used with friction shifters.

I have an old Trek I use as a rain bike that has barcon shifters so front shifting is friction. Originally I had an old SR crank on it and later fitted a used 105 8-speed era crank that has the newer type chainrings. The shifting improvement was dramatic.

Sheldon Brown

Japanese stuff commonly used 14 mm before the switch to 8 mm Allen bolts. Could be 15 mm though. Generally 1/2" drive 15 mm sockets won't fit into the hole, nor will cheapo 3/8" drive sockets.

I have several very detailed articles on these older style bottom brackets in my Tool Tips section https://sheldonbrown.com/tooltips

Sheldon "That Sugino Crank Is One Of The Good Ones" Brown

JanMM

I was thinking more of the crank and not the chainrings.

moxfyre

+1

Newer chainrings just shift a lot smoother.

Much more dramatic, even, is the difference in COGS. You will do yourself a huge favor if you replace an old freewheel with a new one that has shift ramps. With a modern cassette, I can friction shift so smoothly that I am happy to use friction bar-ends exclusively on my commuter bike.

daotan

ok i got one side off, i even got the bottom bracket unscrewed, you're all gonna tell me that i have to remove both cranks right? because i sure still cant get it off!

moxfyre

Wait... *what* can't you get off now? I'm confused. Is the goal to get the cranks or the BB off?

jgedwa

Once the bolt has been removed from that crank, the crank arm is still held on by quite a bit of friction. Basically, when the bolt was tightened down it press fit the square tapered end of the BB spindle into a square tapered hole in the crank arm.

It will not just come off, now that the bolt is removed. There is a tool (crank arm puller) that is specially made for this. An outside sleave threads into the threads that the dust cover was screwed into (hence, why those threads should be preserved or else the crankarm is basically junk), and then an inner post threads into that outer sleave and pushes the spindle out of the hole as it tightens down.

The tool is not expensive, and any of the shade-tree mechanic (I can say that, I am one) techniques to avoid this tool are marginally effective, and often ruin the crank. Either buy it, borrow it, or pay the LBS people to do it. They will not charge much.

Also, if you are completely desperate, only one crankarm has to be removed to get the BB out. But once you figure out how to get one side out, getting the other out will take another 30 seconds. With the right tool that is.

jim

moxfyre

+1

With the $5 crank puller tool, removing a crank arm is trivial. Without it, it's an absolute nightmare, and as likely to end up with a ruined crank as not.

Get the tool.

daotan

you guys are great thanks

relyt

Just to let you know, I have a Sugino VP crank that looks like yours, it is actually a compact double. I had a really hard time finding info on the internet regarding what length BB to use with it. The only info I could find was that a few people had luck with 115mm.

Well, I am pleased to report that 115mm is the right size, it works great. I got a Shimano UN-54 bottom bracket for it. I have 130mm rear spacing, if you have an older bike with 126mm spacing, then 113mm might work but it would be close.