Hmm... crank bolts won't undo?

Northwind

I'm planning to swap the crankset and BB from my Kraken onto the new frame (if it ever ******* arrives), so I was just doing some checks today for compatability... And while I was playing, I discovered I can't shift either crank bolt. It's a Truvativ Isoflow crankset, and seems to be on a powerspline BB. The crank bolts are marked "maximum 40nm", so I'd expect to be able to shift them with regular tools, but there's not a trace of movement.

So, I've zapped them with plusgas, and I guess I'll put some heat onto the bolts before my next attempt in case they've been euberantly threadlocked. But I just want to rule out the blatantly obvious- there are conventional threads (ie lefty loosey) aren't they? I might cry if I've just pointlessly spent 20 minutes turning them the wrong way

Other than that, any suggestions? It's a nice big allen bolt, M8, so if the worst comes to the worst I'll attack it with a breaker bar or impact gun but I'd really sooner not!

(Actually, there's always Plan C, which is "Get a new crank and BB", since I was planning to do that in a few months anyway, and rebuild the Kraken to standard for a spare or to sell. But I don't like that idea much)

Salsa

Drive side is undo towards back of bike, non drive towards front of bike (so normal).
I have had trouble getting various bolts/parts off a bike but a crank bolt is not one of them. Just get a pipe over a 8mm allen key & muscle it off, I just use a 12" torque wrench with a 8mm key socket & one good grunt gets the tightest crank bolt off in my experience.
It's certainly not a good idea to loc-tite them on though & I'd be surprised if they have been.

Yukon Lad

if they won't move cos they're seized drench it with light oil (such as GT85) before trying to muscle it off else you may damage you bike

Yukon Lad

nonnac85

"Just get a pipe over a 8mm allen key & muscle it off"

My dad had to stand on the pipe to get the bolt undone when i had these cranks!! Not the best way to get them undone but it worked after we had tried the GT85 and that hadnt helped :?

Northwind

Yukon Lad wrote:

if they won't move cos they're seized drench it with light oil (such as GT85) before trying to muscle it off else you may damage you bike

Yeah, already doing that with a real penetrating oil (Plusgas is what you want for jobs like this, or similar). I can't really see them being seized though, it's a year-old bike without much use on it. But it's possible of course, depends how cheap the BB was to some extent.

Well, cool, I've not shifted it yet but I'm more comfortable just muscling it now, I was worried that I might be missing something obvious (like a left-hand thread)

Northwind

Finally budged them tonight, using a pair of 4 foot scaffold pipes :shock: Looks like the previous owner was fairly strong No apparent damage from the overtightening though, so it's on to the next step. Thanks for the help!

johnsav

goes to show that assembly grease is always a good idea...

Northwind

Yup. Who would have thought that Halfords of all people might not assemble a bike too well The bolts had a dab of grease near the end of the thread, as if someone had plonked a tiny bit into the bottom of the bolt hole in the BB, but most of the thread was dry. I don't think it'll have any other surprises lurking now though, hopefully I have slain the beast and now I can steal its treasure and make another bike with it.

PS, Carrera Kraken frame and forks for sale. 2 careful owners :shock:

Vivid

Northwind wrote:

Yup. Who would have thought that Halfords of all people might not assemble a bike too well The bolts had a dab of grease near the end of the thread, as if someone had plonked a tiny bit into the bottom of the bolt hole in the BB, but most of the thread was dry. I don't think it'll have any other surprises lurking now though, hopefully I have slain the beast and now I can steal its treasure and make another bike with it.

PS, Carrera Kraken frame and forks for sale. 2 careful owners :shock:

Cranks come fully attached and bolt inserted from the factory

Northwind

Hmm, I saw them fitting a BB and cranks to a new bike in my local. Ah, but maybe they'd robbed it for parts, they did the same from their stock kraken when my freehub broke.

I take it back! (Actually, my local Halfords is pretty damn good, I still don't use them for servicing since i do my own but they do decent work, and their parts service is good- see above, they couldn't get a freehub for mine within a week so they just took it off the display model instead)