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5

This frame either uses a BB386 Evo "standard" or a Pressfit 30 "standard". You can determine which by measuring the width of the frame at the BB shell. If 86.5mm it is BB386Evo. If 68mm it is Pressfit 30. If it is a Pressfit 30(68mm shell) this BB is a direct fit for the Shimano crank without extra spacers. this is the PF30 version of the BB30 bottom ...


4

There is no difference in the fit expected based on road vs mountain. I thought I would be able to provide tolerance numbers from the original BB30 technical documents put out by Cannondale. They used to be at www.bb30standard.com, which is defunct now but can be found on Wayback. However, turns out it seems to have only ever had shell dimensions. The spec ...


2

As you found in your research, BBRight is based off of the BB30 standard, differing only in the placement of the bearings relative to the centerline of the frame. Shimano has never really supported BB30 or any of the related BB standards, instead steadfastly maintaining compatibility with their own Hollowtech II (24mm) standard. This means that any frame ...


2

The fit off the axle in the bearings needs to have no play between the race and axle. The axles are designed to be tighter than a 'slip' fit, but not a full 'interference' fit. This means the axle will go through the bearing inner race with a little force. Often, hand force is not enough. You can use a soft mallet to carefully tap the crank through the ...


2

The left arm has no threads because that side is designed never to be separated from the spindle... From what I can find, that's an M18 thread, pitch unknown but probably M18x2.0mm or M18x1.5mm. Remove the right arm, put the spindle down through a sturdy surface with a hole no larger than 31mm so the metal part of the left arm has maximum support. Screw a ...


2

Whoever wrote their product specs was probably confused, because "BB86.5" isn't really a thing. You have an FSA 386EVO crank. All the bikes in this series seem to have come with them. You probably have a BB386EVO shell. If not that, then it's probably a BB86 shell. This would require a fancy adapter bottom bracket to work with those cranks, which ...


2

I had this, Cannondale 2019 Optimo, FSA crankset was knackered and needed replacing, the crank that was attached to the axle (?) was supposed to be one solid piece but it was coming apart. FSA cranks are junk from what I've heard, at least the ones fitted by bike manufacturers, they might have some better aftermarket cranks available. Bike shop initially ...


1

As of now, this issue seems practically unsolvable. My replacement spindle is a niche item that very few manufacturers produce (none in exactly matching length) and almost no bike shop stocks, at least in the EU. (For the record, I add one more manufacturer to the list: Leonardi Factory. But they seem to have gone out of business.) I'm left with no other ...


1

Looking at the Praxis web site it looks like M30 is a proprietary BB and you need a specific Praxis M30 to BB386 adapter. Strange that you tried PF30 BB units in a BB386, but I think maybe the cups and bearings are the same. According to https://www.bikeradar.com/advice/buyers-guides/the-complete-guide-to-bottom-bracket-standards/ they both use 6806 ...


1

If your BB uses a threaded interface, there will be a tool interface. For Shimano Hollowtech II style cranksets, threaded BBs sit outboard of the frame with notches needed by the tool clearly visible. Frames which use Shimano BB86/BB92 pressfit BBs use a wider BB shell. The pressfit cups will have a thick lip that prevents them pushing deeper into the ...


1

In the first picture it looks like the holes are simply machined to decrease the weight of the adapter without compromising strength. My only concern with the frame and adapter would be tolerances because you wouldn't want it to fit too loose. The second picture definitely looks like a bb30 frame but without calipers it's impossible to know the diameter and ...


1

From what I can see the various "MegaExo" BB labels refer to the spindle size and crank fixing, rather than the size of the shell in your frame. There will be subtleties with frame clearance, but that's something for Giant rather than the BB or crankset people. From that website I got this screenshot: You will need a HollowTech II BB, or some that's ...


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