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*Please don't let this become an oil debate, but here is my guide.
Aufitt, you know the photo showing those bottles of GN4 will be all it takes to spark up an oil debate. I'll wager you one (1) genuine Honda crush washer*, that the next several pages of this thread will spin off into a full blown Rotella vs. Amsoil vs. Mobil1 vs. Castrol vs. Motul vs. ________ (fill in the blank). Of course we can't forget the 5W-30 vs. 10W-30 vs. 10W-40, and the full synthetic vs. ODDJ (Organic Dead Dino Juice) aspect to the debate.

As straight forward and easy to understand as your Oil Change Guide is, there will always be those few who, just like when confronted with a wet dream, will figure out how to thoroughly screw it up... remember when we tried to advise DudeMan that using his cheap $10 Harbor Freight 1/2" drive torque wrench to tighten the oil filter cover bolts was a really bad idea, and he responded by serving up his famous turd sandwiches. Yup, seems like only yesterday... classic DudeMan modus operandi.

* Including postage... I figure postage from the U.S. to AU (or vise versa) shouldn't be more than 10 times what the crush washer is actually worth. :rolleyes:
 

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Rotella vs. Amsoil vs. Mobil1 vs. Castrol vs. Motul vs. ________ (fill in the blank). Of course we can't forget the 5W-30 vs. 10W-30 vs. 10W-40, and the full synthetic vs. ODDJ (Organic Dead Dino Juice) aspect to the debate.
I bought 2L of Motul 10w-30, filter and crush washer because it was cheaper than buying the GN4 10w-40 change kit by about $30. ;)

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Aufitt, you know the photo showing those bottles of GN4 will be all it takes to spark up an oil debate. I'll wager you one (1) genuine Honda crush washer*, that the next several pages of this thread will spin off into a full blown Rotella vs. Amsoil vs. Mobil1 vs. Castrol vs. Motul vs. ________ (fill in the blank). Of course we can't forget the 5W-30 vs. 10W-30 vs. 10W-40, and the full synthetic vs. ODDJ (Organic Dead Dino Juice) aspect to the debate. :rolleyes:


(I'm tooooo cheap to buy that, so I just use Honda's recommended stuff.)
 

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You can get them from Fastenal... however changing to a stainless steel version isn't going to prevent someone from over tightening them and pulling the threads out. I've had no problems with the OEM bolts that Honda uses.
I've had no problems using a nut driver on these bolts in 3 oil changes so far either, but I had the advantage of reading about the problems others were having with breakage before I attempted my first oil change on the bike. It's too bad Honda couldn't include a specific warning about over-tightening these bolts with a torque wrench in the manual since I'm sure there are many new CBR250R owners who aren't members of this forum.
Considering how many times I've seen the problem posted here it at least deserves a footnote in the manual for do-it-yourselfers. I've owned several bikes from different manufacturers in my life, but none had bolts so prone to breakage and stripping as these.

Its a poor carpenter that blames his hammer.
Even the best hammer on the market won't consistently drive cheaply-made nails home without a lot of bending and breakage. Honda quality may be well-known in the industry, but where the oil filter cover bolts are concerned I at least expect serviceable parts that will hold up to repeated use and I don't think that's what we actually got here. Especially on a "beginner-friendly" bike like the CBR250R new owners should be able to do a simple oil change without worrying about causing expensive damage or losing the use of the bike because of a broken oil filter cover bolt.
 

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Its better that ham fisted muppets break a thread or even strip the housing threads than crack the engine case.

Once a little 6mm bolt with a little 8mm head is tight, logic says you don't keep going.
 

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Once a little 6mm bolt with a little 8mm head is tight, logic says you don't keep going.
Amen, but not to much logic or common sense left in the world.

(BTW for those anal types out there M6 (Class-2 steel) threads are about 3in-lbs for .500" thread engagement, Class 5 SST bolts are 5in-lbs)
 

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Amen, but not to much logic or common sense left in the world.

(BTW for those anal types out there M6 (Class-2 steel) threads are about 3in-lbs for .500" thread engagement, Class 5 SST bolts are 5in-lbs)
Anal enough to know there are no property class 2 or 5 in the metric system and 3 inlb isn't even finger tight.
 

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... (BTW for those anal types out there M6 (Class-2 steel) threads are about 3in-lbs for .500" thread engagement, Class 5 SST bolts are 5in-lbs)
Do you mean ft.-lbs.?

Also specific torque specs, or values would be dependent on the various metals that the bolt is threading into, i.e. a given size/grade bolt threading into a steel casting could be torqued to a higher value than the same size/grade bolt threading into an aluminum alloy casting, and so on.
 

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Do you mean ft.-lbs.?

Also specific torque specs, or values would be dependent on the various metals that the bolt is threading into, i.e. a given size/grade bolt threading into a steel casting could be torqued to a higher value than the same size/grade bolt threading into an aluminum alloy casting, and so on.
Nope inch pounds, per mechanical engineering handbook and sae formulas. the values I have been giving are based on grade 2 steel going into aluminum with 1/2 inch of engaging. When I get back to work I'll submit the formulas so anyone can do it. Though it is stipulated that these values are only a starting point.

Btw you would be correct (ft-lbs) if it was steel threading into steel

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Nope inch pounds, per mechanical engineering handbook and sae formulas. the values I have been giving are based on grade 2 steel going into aluminum with 1/2 inch of engaging. When I get back to work I'll submit the formulas so anyone can do it. Though it is stipulated that these valUes are only a staggering point.

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Its a sad thing when dementia sets in.
 

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Its a sad thing when dementia sets in.
isn't it lol, forgot to underline the staggering.... darn autocorrect

Company i work at we use ~30% of recommended in our formulas. As most of what we do is aluminum to aluminum mating. Just like our brazing is based on MIL-B-7883B

Calculator
FUTEK Bolt Torque Calculator | Bolt Torque Calculators

Major Bolt Diameter: 0.138 in
Bolt Thread Pitch: 32
Bolt Proof Strength: 55000 psi
Recepticle Length: .5 in
Recepticle Strength: 40000 psi
Applied Tensile Load: 0 lb
k Factor: 0.2

Recommended Torque
8.62 in-lb
(0.97403 N-m)
Resultant Tension:312.31 lb
Maximum Torque
11.493 in-lb
(1.2987 N-m)
Resultant Tension:416.4 lb
 

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isn't it lol, forgot to underline the staggering.... darn autocorrect

Company i work at we use ~30% of recommended in our formulas. As most of what we do is aluminum to aluminum mating. Just like our brazing is based on MIL-B-7883B

Calculator
FUTEK Bolt Torque Calculator | Bolt Torque Calculators

Major Bolt Diameter: 0.138 in
Bolt Thread Pitch: 32
Bolt Proof Strength: 55000 psi
Recepticle Length: .5 in
Recepticle Strength: 40000 psi
Applied Tensile Load: 0 lb
k Factor: 0.2

Recommended Torque
8.62 in-lb

(0.97403 N-m)
Resultant Tension:312.31 lb
Maximum Torque
11.493 in-lb
(1.2987 N-m)
Resultant Tension:416.4 lb
First off, the fastener that you selected in your calculator is a #6, not a 6mm... big difference. That #6 screw diameter of 0.138" is close to the size of a 3mm screw, which is pretty small and explains why only 8.62 in-lbs. of torque would be use for that size fastener.

When talking about specific torque values for specific fasteners on a Honda motorcycle, Honda states in their Common Service Manual: "Torque values are determined according to fastener size and strength, and the strength of the parts that are fastened together. In many of our previous service manuals, torque values are specified within a certain range. Due to slight variations in torque wrench precision and fastener friction co-efficient, the target torque value should be the middle of the range of the torque value specified. The Model Specific manuals provide only the simplified, middle range torque values."

The 6mm oil filter cover bolts used on the CBR250R call for a specific torque value of 9 ft.-lbs. (12 N-m, 1.2 kgf-m) or 111 in.-lbs., which would be the "middle" of the torque range for this bolt, as described in the paragraph above.




.
 

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That thing should be called the FUBAR thread calculator.

Thread pitch is the inverse of threads per inch. Anyway, try using 1/4 inch bolt in the fubar calculator, (which is still smaller than 6mm)
 

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That thing should be called the FUBAR thread calculator.

Thread pitch is the inverse of threads per inch. Anyway, try using 1/4 inch bolt in the fubar calculator, (which is still smaller than 6mm)
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.
 

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probably should footnote that if the threads have any lube like many guys use such as oil or anti seize or Teflon, moly, etc, the applied torque needs to be reduced 20% or more depending on the lube.
 
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