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Fubar... there ya go. ;)



At the top of that calculator, you can select Metric. I looks like when you first open that link, the calculator defaults to American (instead of SAE :rolleyes:). Anyway, after setting the calculator to metric, I plugged in the M6-1.0X25 bolt and low and behold, the calculator came back with the very same torque value that Honda specifies in their manuals... 9 ft.-lbs. Simply amazing.

Don't forget tot adjust the K factor to .12-.14, the 2.0 represents dry. And while you could argue they are dry that would require both the bolt and hole to have absolutely nothing. And using M6, .14 for k factor ~.500 engagement strength grade 2 bolt going in a 6061 aluminum block ( I could be wrong and the block is made of steel). Comes out to 3.9nm (2.9 ft lbs) recommended, I get it you don't like me. Most people don't, but trying to discuss it a intellectual way is all I'm trying to do. Yes I have my opinions and so does every one else, and opinions are like a culo every one has them and they all stink. Doesn't mean we have to be rude and tease, insult, and/or bully.

(Edit: Added m6, forgot to add the bolt thread. I'm human too)

Forgive me for not explaining in Si format; just because I do not converse and/lecture at the level of education I have obtain in life. This does not mean I do not know what I am talking about when it comes to mechanical engineering. As to insulting a tool based on a level of science and knowledge beyond most individuals, for what ever your reasons or intentions may be. Is more insulting to yourself; and I do regard your as an educated and well versed individual with mechanical knowledge in a real world format. But in the way of how and why that was required for engineers to build and design, you have left me at a disappointment. Maybe it was my fault for trying to explain physics a manner consistent to that my professors had to explain to me. As in when it comes to thread torque, the bolt is based on designed clamping pressure the engineer wanted. IE while T=cDF, F is elusive and has to many variables to calculate properly without knowing the design intent. If the design was 9ft-lbs (12.2nm), ~1032kg clamping force, then the engineer used the wrong bolt and should have used an M8 thread with over 12mm of engagement not an M6. Optionally, could use a higher grade bolt like a class 12.9 instead of 4.6 or 4.8. Engineering principles do not change because a company is larger or makes a decent product.

Now; why would an engineer or person (let's say myself) would want to try to figure if the proper torque is the one the manufacturer has specified. In virtue would most likely be because a bolt or fastener has failed. Most often because structural failure or simply put "it broke".

It's not the (Vf = Vi+at) That kills you, it's the (F=m(deltaV/deltaT))
(Btw it's not "fall" and "impact")

I apologize to the for verbalizing such a discourse.
Sent from Motorcycle.com App
 

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Don't forget tot adjust the K factor to .12-.14, the 2.0 represents dry. And while you could argue they are dry that would require both the bolt and hole to have absolutely nothing. And using M6, .14 for k factor ~.500 engagement strength grade 2 bolt going in a 6061 aluminum block ( I could be wrong and the block is made of steel). Comes out to 3.9nm (2.9 ft lbs) recommended, I get it you don't like me. Most people don't, but trying to discuss it a intellectual way is all I'm trying to do. Yes I have my opinions and so does every one else, and opinions are like a culo every one has them and they all stink. Doesn't mean we have to be rude and tease, insult, and/or bully.

(Edit: Added m6, forgot to add the bolt thread. I'm human too)
My reply posts regarding technical subjects have nothing to do with whether I like you, or dislike you... honestly, I don't know you (or for that matter, anyone here on the site who is relatively new) personally to even have a sense of "like/dislike". When the topic of discussion is of a technical nature, hard facts carry far more weight than opinions ever will. In the case of this topic of bolt torque, I didn't express any "opinions", rather my reply post were based on what Honda specifies... whereas your posts seemed to contain opinions based on misinformation. For example, your post was just basic misinformation when you were insisting that 3 inch-pounds was the right unit of torque measurement for these oil filter cover bolts.

BTW, the "Fubar" reference wasn't directed at you personally, but rather to the Torque Calculator that was linked to. To use that calculator accurately requires access to far more Material data and technical information than anyone other than a mechanical engineer employed by an OEM manufacturer (in this case Honda Motor Co.) could possibly have. I know that I certainly don't have access to that kind of Material data and info...and since you don't work for Honda, one can safely assume that you don't either. Using such a torque calculator without having all the pertinent data and info, leaves one open to a huge margin of error... which by all measures of reason, makes such a calculator useless.
 

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Don't forget tot adjust the K factor to .12-.14, the 2.0 represents dry. And while you could argue they are dry that would require both the bolt and hole to have absolutely nothing. And using M6, .14 for k factor ~.500 engagement strength grade 2 bolt going in a 6061 aluminum block ( I could be wrong and the block is made of steel). Comes out to 3.9nm (2.9 ft lbs) recommended, I get it you don't like me. Most people don't, but trying to discuss it a intellectual way is all I'm trying to do. Yes I have my opinions and so does every one else, and opinions are like a culo every one has them and they all stink. Doesn't mean we have to be rude and tease, insult, and/or bully.

(Edit: Added m6, forgot to add the bolt thread. I'm human too)

Forgive me for not explaining in Si format; just because I do not converse and/lecture at the level of education I have obtain in life. This does not mean I do not know what I am talking about when it comes to mechanical engineering. As to insulting a tool based on a level of science and knowledge beyond most individuals, for what ever your reasons or intentions may be. Is more insulting to yourself; and I do regard your as an educated and well versed individual with mechanical knowledge in a real world format. But in the way of how and why that was required for engineers to build and design, you have left me at a disappointment. Maybe it was my fault for trying to explain physics a manner consistent to that my professors had to explain to me. As in when it comes to thread torque, the bolt is based on designed clamping pressure the engineer wanted. IE while T=cDF, F is elusive and has to many variables to calculate properly without knowing the design intent. If the design was 9ft-lbs (12.2nm), ~1032kg clamping force, then the engineer used the wrong bolt and should have used an M8 thread with over 12mm of engagement not an M6. Optionally, could use a higher grade bolt like a class 12.9 instead of 4.6 or 4.8. Engineering principles do not change because a company is larger or makes a decent product.

Now; why would an engineer or person (let's say myself) would want to try to figure if the proper torque is the one the manufacturer has specified. In virtue would most likely be because a bolt or fastener has failed. Most often because structural failure or simply put "it broke".

It's not the (Vf = Vi+at) That kills you, it's the (F=m(deltaV/deltaT))
(Btw it's not "fall" and "impact")

I apologize to the for verbalizing such a discourse.
Sent from Motorcycle.com App
Ok. We all see now how smart you are.
 

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Ok. We all see now how smart you are.
Guess I am use to military standards where things have to be blown up and the person walks away. So my knowledge is not practical for most people to use.

And "Yes" i am an idiot... i am human...
Only defense i have is psychology states we need to vent.
 

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82 - responses here are necessarily text
and relatively brief [he ducks] thus there will
always be different interpretations of words
thus ideas/concepts/responses expressed..

even einstein was wrong ['cosmological constant']
and his error greatly embarrassed him and cause
him great concern.. most rational people tho
recognise einsteins contributions to physics etc
regardless of his cosmological constant..

those who argued the toss over the cosmological
constant [etc] were expressing valid responses
to the idea, not as dislike of albert himself..
this or any such forum needs input from all sides
of a question.. thats what makes it a forum..

members here are manifestations of a global community
of more or less like minded individuals with common
interest in a particular motorcycle and motorcycling..

seems to this member that motomike
as member and, as moderator,
stays well within the bounds of
rational and considered responses..

i dont see malice or dislike of individuals
here based on their various expressions
about mechanical or related subjects..

bottom line mate, dont take it personally,
 

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FYI, considering I just went through the same, the oil filter bolts are the same size as the ones holding the sprocket cover onto the other side of the engine:

Honda Motorcycle Parts 2012 CBR250R AC LEFT CRANKCASE COVER Diagram
(Number 4 in that diagram)

Cannibalized one for now to get the bike up and running, and will pick up another next week to replace the one I borrowed from the cover.
 

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FYI, considering I just went through the same, the oil filter bolts are the same size as the ones holding the sprocket cover onto the other side of the engine:

Honda Motorcycle Parts 2012 CBR250R AC LEFT CRANKCASE COVER Diagram
(Number 4 in that diagram)

Cannibalized one for now to get the bike up and running, and will pick up another next week to replace the one I borrowed from the cover.
Thank you. Just broke my first bolt tonight and have been getting ever more desperate while looking for new bolts online - we don't have a dealership anywhere close!

Now going to ask the silly question. You linked the 2012 model, think it will be the same with the 2013?
 

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Thank you. Just broke my first bolt tonight and have been getting ever more desperate while looking for new bolts online - we don't have a dealership anywhere close!

Now going to ask the silly question. You linked the 2012 model, think it will be the same with the 2013?
It's the same bolt... in fact the only differences between 2011, 2012, & 2013 CBR250R's are the paint and graphics on some model years.
 

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It's the same bolt... in fact the only differences between 2011, 2012, & 2013 CBR250R's are the paint and graphics on some model years.
That's what I figured, but thought I better double check. My confidence has taken a hit after breaking this bitch.

Any tips to getting it out?
 

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I usually replace these types of cover bolts with socket heads and then tighten them by hand/feel with an allen wrench. I'm not saying this is for everyone but after 45 years of messing with this stuff and 150 bikes you get a feel for it. The allen wrench gives me better feedback than a hex head bolt and wrench.
 

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I see a lot of advice to snug the bolts and then give them another 1/4 turn. Not sure if that's really good advice in retrospect.
Once I snug up the oil filter cover bolts I'm lucky if I can get another 1/8 turn out of them before I start worrying about snapping a bolt.
Sometimes I don't even get that.
No leaks or broken bolts in a half-dozen oil changes so far, but it's still nerve-wracking every time I do it.
At this point I think that if it feels tight it probably is and any further effort to tighten it more is probably a bad idea.
I hope nobody is cranking that extra 1/4 turn just because they read it here. Could be the difference between tight and broken.
I had the same experience recently tightening the bolts on my left crankcase cover. Once they were tight none of them were going to take another 1/4 turn without putting them in serious danger of breaking.
Really makes me question the long-term maintenance prospects for my lil' Honda, but I guess it is what it is.
 

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Thanks, TrueFaith. I have a torque wrench that reads in inch*lbs and is intended for motorcycles. That's what I ended up using since I couldn't find a written spec.
 

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Just snug enough to keep it from leaking is enough.

Snug it down with a 1/4" drive ratchet and keep an eye on it for leakage. If it shows signs of leaking, add 1/8 turn (EDIT: maybe closer to 1/16) until it stops.

Better to drip a couple drops than snap the bolts.

You need to learn to go by feel. Small bolts are designed for small amounts of torque. Use a 1/4" drive ratchet on all small bolts and learn what "snug" feels like.
 
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