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What the f*ck is this allen bolt size

4K views 23 replies 5 participants last post by  KeepTheFeather 
#1 ·
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So I want to remove my exhaust to clean the rear caliper and I guess it came with an allen bolt? (bottom one on the pic) Every video I see of someone removing a cbr 250r exhaust shows it with an hex bolt and yet for SOME REASON mine came with this abomination. Soo... Is this normal? And if so does anyone know the size of it so I can buy an adaptor. Thanks lol
 
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#3 · (Edited)
I got to perform cleaning and replacing pads. Yes, the access is inconvenient, but I did not lower the muffler. And if you want to take down the whole assembly for renovation then you need to disassemble the rear wheel.

Yes, your screw is not original.
Check out my photos and decide if it's a problem? (I do not think there is a problem).
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As for your screw head, it looks like Alan 6mm. Measure it before you buy.

For disassembly and cleaning of the caliper you need a lot of patience, knowledge... and the study costs money (the mistakes you make, the purchase of the appropriate professional literature, the purchase of tools ... etc.) ...
Because it's a matter of safety, maybe...feel free to contact a professional mechanic who will do that job for you.
 
#4 ·
Yeah maybe I will hold off on it then. So I need to remove the back wheel to remove the caliper from the rotor? I did remove the front one and cleaned it and replaced the pads and that was quite easy but I definitely dont want to remove the back wheel thats a bit beyond me.
 
#8 ·
... I need to remove the back wheel to remove the caliper from the rotor?
NO
why anyone would remove the hex
A mechanic who improvised a screw, it happens all the times, the rubber is there?
... im working with the non ABS version
OK. To the best of my knowledge, in rear brake, this is the same procedure in both ABS & non ABS.
what I wanted to do was pretty much this
No. It's more like this:
 
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#7 ·
Sorry for responding so many times. So what I wanted to do was pretty much this

So I just wanted to remove the caliper from the rotor so I could access the insides better and be able to clean inside with brake cleaner and put copper paste on the pistons without a problem. So what I did for the front but in this video it just seems I need to remover the exhaust to do it. Do you think I should be doing these things? The only thing that worries me is not having a torque wrench but I memorized how much I needed to turn the caliper screws to snug them back to how they were.
Thanks Tamir!
And btw the chain alignement is still a work under progress lol
 
#9 ·
Get help from PARTZILLA (LIINK) diagram parts.
Check that all the parts are back in to their place. especially:

PAD SPRING
43108-MBB-006
RETAINER
43112-KT7-761
 
#10 ·
If you wanted to clean caliper, you'll have to remove muffler to get caliper off swingarm. The sliding pin bolts will bump into muffler and won't let you remove caliper. Should also remove the sliding sleeves from caliper, clean and grease with hi-temp silicone grease. This is more important maintenance than lubing piston to pad interface. Your original video shows proper procedure.

Also don't use little L-shaped allen keys or combo tools. Get set of allen-key sockets so you can use ratchet wrench for stability and adequate torque.

 
#11 ·
The sliding pin bolts will bump into muffler and won't let you remove caliper.
Yes. But...
It's possible, I did it, but you have your point.
Disassemble more parts to improve access, compared to overall work efficiency? There is not always a match between the two approaches. These are two different approaches, each with its own pros and cons. For example: If disassembly muffler job is failing: A broken screw, or if the GASKET, MUFFLER 18392-KYJ-901 ring is torn ... We are not in 2011, our motorcycles are aging with us ... "What works is not worth touching" is a leading approach in maintaining old motorcycles. In unlimited time and unlimited budget the other approach wins.
 
#13 ·
Yeah thats what I ended up doing. Removed the 12mm back bolt and just slid the caliper up instead. Much simpler.

However brace for the sad, dreadfull, depressive and dark end to this.
I cleaner everything, the pistons the calipers, all the pins and right spots lubricated with silicone grease. Put the new pads in, even did a brake fluid bleed that went great.

AND THEN

As I was tightening the 12mm screw, I assume I over tightened it because CRACK. The screw broke. A clean break right at the entrance of the bottom hole. Meaning that now I have the broken tip of the screw screwed in the hole with no way to remove it and to top it off a loose caliper.
Saying I was pissed would be an understatement.
The only solution I see is getting a tow to a nearby garage and hoping they can remove the tip, oh and buying a new screw from Honda, fun!

Im pissed and screwed by a screw.
 
#14 ·
Saying I was pissed would be an understatement.
It happens to everyone, it can happen to veterans as well:cautious:. In this case it is important to stay away from the machine:coffee:, and not return to it until you relax:giggle:, and then of course find a solution and make the repair.
The small problem is the length of the job, the big problem is if you increase the damage just because you are angry.

I think you can deal with the problem. To solving a problems It's fun. But if there is no time, or patience is over, then it is clear that it is better to go to a qualified mechanic.
Just do not be angry with yourself, it happens to all of us, even to qualified mechanics.
 
#16 ·
Yeah i've cooled off now lol. Thanks! 🙏🙏
I might buy a screw extraction kit. Problem is its sideways, so im worried tapping hard on it might damage something.
Ill probably end up going to the professional to get it out lol
If you have the time and patience fix it yourself. This will be an important study chapter for you.
Take off the muffler, screw out the front caliper screw, loosen the pads ... maybe you should also loosen the mudguard and the brake hose? ... then you will see if you need to buy a extract tool and which tool you need. Please take a picture that we see what it is all about? Thanks.

P.S. Maybe during the disassembly you will find that you need some more spare parts, this too can happen. Patience + time + money, that's part of the D.I.Y hobby.
 
#18 ·
As for the fix. I dont feel very confident drilling it especially when I cant take the wheels off. Hammer extraction could work but that would take removing the exhaust. Which would take quite a few tools. Allthough I have a long T wrench the muffler ring bolt at the bottom has been fastened up so that I cant get a socket perpendicular to it. So it would take a wrench. My 1/2 wrench is too big for the space. The small normal spanners dont have enough leverage. I think I will rely on the mechanic ofr this issue, because I am not sure what tools are needed. Wouldve been so much easier if garages assembled parts properly :/
 
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