Spun Crank Hub 6MT

fmorelli

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Never heard a n54 auto spinning a hub unless second hand parts where reused during a rebuild.

N54's,with stock clutch is also highly unlikely.

Now where I've seen failures are, which includes F series

DCT is quite common in high power applicstions across e and f platforms.

Manuals fitted with single mass flywheels and/or twin plate clutches where dropping the clutch or lightning fast gear changes can put an abnormal stress on the hub due to abrupt rpm changes.
Let me say what I heard you say, differently. BMW redesigned the hub for the S55 and we N54 guys got downstream benefit, that it fits our cars. After all I'm sure you'll agree - BMW's redesigned hub for the S55 (and N54) came out AFTER BMW had well stopped producing these vehicles (2019).

Second, and I'm grasping at this one - the CBC was not included (ala S65) on the S55 solution because BMW had no issues with the bolt backing out on the S55? So they only did the crank hub update?

I get your points on modified cars and BMW's view (and I agree with that). But I'm baffled as to
1) why BMW even came out with the hub update, well after 99% of those cars were out of warranty.
2) why the CBC was not also produced for the S55 update hub, when they took the time to do the hub (and the S65 has it).

My questions make sense?
 

SlowE93

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Let me say what I heard you say, differently. BMW redesigned the hub for the S55 and we N54 guys got downstream benefit, that it fits our cars. After all I'm sure you'll agree - BMW's redesigned hub for the S55 (and N54) came out AFTER BMW had well stopped producing these vehicles (2019).

Second, and I'm grasping at this one - the CBC was not included (ala S65) on the S55 solution because BMW had no issues with the bolt backing out on the S55? So they only did the crank hub update?
Yes man, understand that they did all this because they intentionally want N54s to keep spinning hubs for warranty denial on cars that have no warranty anymore anyways. They also took the time to redesign the friction discs to fool you into thinking they are trying to help with the issue. When in reality the CBC is what they needed to provide, but once again. Denied Warranty claims and charging people straight up is where the Chedda is to be made.
How can this not make sense to you FFS ????
 

wheela

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Let me say what I heard you say, differently. BMW redesigned the hub for the S55 and we N54 guys got downstream benefit, that it fits our cars. After all I'm sure you'll agree - BMW's redesigned hub for the S55 (and N54) came out AFTER BMW had well stopped producing these vehicles (2019).

Second, and I'm grasping at this one - the CBC was not included (ala S65) on the S55 solution because BMW had no issues with the bolt backing out on the S55? So they only did the crank hub update?

I get your points on modified cars and BMW's view (and I agree with that). But I'm baffled as to
1) why BMW even came out with the hub update, well after 99% of those cars were out of warranty.
2) why the CBC was not also produced for the S55 update hub, when they took the time to do the hub (and the S65 has it).

My questions make sense?
I agree. My suspicion as to why BMW didn't incorporate cbc into the improved s55 solution is that they realized it doesn't help the problem.
 
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fmorelli

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My point in the questions ... seriously - 2019 the new hub comes out - please tell me how many S55 and N54 cars are under CPO (they are ALL out of factory warranty) and costing BMW on repairs. What class action / NHSTA concern do they have around spun hubs. Serious question - forget the CBC for a minute - why did BMW even come out with a new hub in 2019 for defunct motors. Literally ... I have worked with BMW NA and AG for many years when I had a business in the space. I can assure you 110% they don't give two shits about cars out of 1) production, 2) warranty. It's a serious question - I wondered this the first time I saw there was a new hub.
 

TheFixer

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Let me say what I heard you say, differently. BMW redesigned the hub for the S55 and we N54 guys got downstream benefit, that it fits our cars. After all I'm sure you'll agree - BMW's redesigned hub for the S55 (and N54) came out AFTER BMW had well stopped producing these vehicles (2019).

Second, and I'm grasping at this one - the CBC was not included (ala S65) on the S55 solution because BMW had no issues with the bolt backing out on the S55? So they only did the crank hub update?

I get your points on modified cars and BMW's view (and I agree with that). But I'm baffled as to
1) why BMW even came out with the hub update, well after 99% of those cars were out of warranty.
2) why the CBC was not also produced for the S55 update hub, when they took the time to do the hub (and the S65 has it).

My questions make sense?
Makes sense.

All we can do is try to make educated guesses why bmw did what they did. Engineers are not flawless, we make mistakes. Sometimes solutions are not really solutions at all but shit coming from higher up to make it look like something was done to make people feel more confident about a product. Hence the updated hub and cbc..... just speculation.

Also despite all the super expensive programs that run thousands of hours of simulations on engines, components etc...... it cannot come close to real world application of product. These simulations also don't simulate the mods we make to our cars.... so these hubs spinning is our own doing. Then we have to come up with our own solutions.... where all kinds of people with different mindsets think that their product is superior....and I'm off on some tangent.....
 

wheela

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Makes sense.

All we can do is try to make educated guesses why bmw did what they did. Engineers are not flawless, we make mistakes. Sometimes solutions are not really solutions at all but shit coming from higher up to make it look like something was done to make people feel more confident about a product. Hence the updated hub and cbc..... just speculation.

Also despite all the super expensive programs that run thousands of hours of simulations on engines, components etc...... it cannot come close to real world application of product. These simulations also don't simulate the mods we make to our cars.... so these hubs spinning is our own doing. Then we have to come up with our own solutions.... where all kinds of people with different mindsets think that their product is superior....and I'm off on some tangent.....
All that said - I think cbc (without a hub keyed to the crank) is a gimmick, but the new desiged hub, while it may not be perfect - increasing the diameter of the friction surfaces will allow them to hold more torque with the same amount of clamp load. I beleive that new solution provides incremental improvement over the previous n54 hub design.
 

JohnDaviz

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All that said - I think cbc (without a hub keyed to the crank) is a gimmick, but the new desiged hub, while it may not be perfect - increasing the diameter of the friction surfaces will allow them to hold more torque with the same amount of clamp load. I beleive that new solution provides incremental improvement over the previous n54 hub design.
One can simply think the increased friction area is not big by looking at the pictures. But it is double or more the area while maintaining the needed clamp force. There is NO evidence or comparison between old and new.

I understand when ppl are in doubt. But my hub was holding 600 ft/lbs easy all day long while abused on the race track. Circuit.. not straight.

Call me idiot. But i am convinced of the design while not running 1kNm.
 
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SlowE93

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One can simply think the increased friction area is not big by looking at the pictures. But it is double or more the area while maintaining the needed clamp force. There is NO evidence or comparison between old and new.

I understand when ppl are in doubt. But my hub was holding 600 ft/lbs easy all day long while abused on the race track. Circuit.. not straight.

Call me idiot. But i am convinced of the design while not running 1kNm.
Dear user, you are an idiot.

































You asked ! 😐

I know, I know, I will go fuck off now ☹️
 

SLOWESTN54

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WIth your luck, your motor will scavenge, back suck some road debris in through the exhaust, wipe one of the turbo impellers, and all that stuff will chuff back through your exhaust valves and N54Destroyer the motor.
It hasn't already? Isn't this you....
Its at about 30 seconds or so
10/10 meme’s lol.
Sorry I’m just catching up on this thread. Didn’t realize how serious it got my bad 🙂
 
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SLOWESTN54

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One can simply think the increased friction area is not big by looking at the pictures. But it is double or more the area while maintaining the needed clamp force. There is NO evidence or comparison between old and new.

I understand when ppl are in doubt. But my hub was holding 600 ft/lbs easy all day long while abused on the race track. Circuit.. not straight.

Call me idiot. But i am convinced of the design while not running 1kNm.
To Further add to this the boys over from N54 Racing channel ran the updated hub in there built motor with no issues. That car was a Xi Manual
2CF938E9-D855-4C0A-8A0F-CF6C86F2A370.png
 

RuskiRacer

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To Further add to this the boys over from N54 Racing channel ran the updated hub in there built motor with no issues. That car was a Xi Manual
View attachment 66686
Yes but not the motor is being sold off after the head allegedly lifted? Seems a little odd that a full 11mm headstud converted block is lifting the head unless your using an autozone head gasket
 

RuskiRacer

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LMAO, I'm still going to full send.

LMAO hey don't blame the messenger.
Hahah definitely not, interesting finding out some of the details now. Really bring up the question of what headstuds he was using as well. Many people use MLS gaskets into the 1000whp range.
 
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martymil

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Let me say what I heard you say, differently. BMW redesigned the hub for the S55 and we N54 guys got downstream benefit, that it fits our cars. After all I'm sure you'll agree - BMW's redesigned hub for the S55 (and N54) came out AFTER BMW had well stopped producing these vehicles (2019).

Second, and I'm grasping at this one - the CBC was not included (ala S65) on the S55 solution because BMW had no issues with the bolt backing out on the S55? So they only did the crank hub update?

I get your points on modified cars and BMW's view (and I agree with that). But I'm baffled as to
1) why BMW even came out with the hub update, well after 99% of those cars were out of warranty.
2) why the CBC was not also produced for the S55 update hub, when they took the time to do the hub (and the S65 has it).

My questions make sense?

One of the reasons I believe they redesigned the hub is because they sell a lot of M cars in Australia and our warranties are not over even though BMW says it is, we have a law stating that the goods should have a life expectancy of determined amount of years as long as the owner followed
the bmw procedure's, I'm not going to go into detail as its determined on a case by case basis.

I've seen a lot of failed crank hub's here in oz, I've seen a perfectly good car hit the dyno with a tune for the very first time and spin a crank hub.

That was on the early cars, then I seen people fit the cbc as a precaution and had no issues with the same year model and same tune.

Coincidence don't think so, maybe who knows.

For a 100 bucks cheap and easy insurance and if it helps even just 20% thats better than nothing.

I personally have them fitted to all my cars and never experienced a hub failure and I have 5 n54's in the last 7 years and they are still perfect as
I know the owners, between me and my mates we had enough failures and seen it all but never have we seen a hub failure.

If I missed a question not meaning to so ask again.