How much pressure is required to install the non drive side crank on a square tapered shaft. Both components are Shimano and both are new. Seems to be stuck half way on. Dot know whether to whack with mallet or try to get it off. My cheap puller broke trying to get it off.

Pic attached

Also, they don't seem to be keyed or anything, is there a wrong position on the shaft to install (provided is is opposite the other crank)

The keying is the square taper. A 90* indexed one. Easy to tell when the arms are not "straight" with each other. As far as retaining bolt/nut tightness the common tapered square is around 30 ft/lbs of torque. New fittings want a second/third follow up tightening after a hundred+ miles of riding. Andy

You have a mismatch between the crank and spindle.

Though the tapers are the same, various brand spindles have different size starting points (the distance across the tip). So, changing the spindle to one that's smaller at the end, will mean that that end will be deeper ito the crank.

To answer your question, it's not a matter of force. Once a crank begins to tighten on the taper, it can only move about another millimeter or two. All the force in the world won't move it deeper, though if you try hard enough, you can split the crank apart.

You don't want the end of the spindle to be flush with the opening in the crank arm. E.g.:

To further elaborate on FBinNN reply. Not all square taper crank and bottom bracket (BB) combinations are compatible. Although nearly all spindles use a 2 degree taper (to match a 2 degree taper in the crankarm), there are two competing standards, defined by the measurement across the flat at the end of the spindle. The JIS size is used by Shimano and most other Asian manufacturers. The ISO size is primarily used by Campagnolo and other European manufacturers.

So yes, make sure your BB is compatible with your crankset.

Sure sounds like an ISO crank on a JIS spindle, but he OP said that both components are new Shimano. One would assume compatibility. I seem to recall that some of the Japanese NJS track stuff was ISO, though.

Can you provide part numbers?

This is what I have. I had to heat it up do get them apart, i wanted to make sure it went on straight. back on the same way. seems the non drive side crank sits out too far, but it is secure.

Shimano UN55 Bottom Brackets
English 68 x 122.5mm
44899-104169 1
@
$18.99 $18.99


Shimano FC-M361 Acera Square Taper Crankset
175mm x 28/38/48t w/ Chain Guard (Black)
43123-100129 1
@
$45.00 $45.00

Yes that Should all go up get another puller. Pusher actually 3 bux on amazon Im about to install similar But bio pace ringed crank arms You might need 68 x 118 generally heating Should not be ness. assembly grease is our friend.

How do the Granny gear on crank (lil one) line up with largest cog on rear cassette should be pretty straight?