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What the f*ck is this allen bolt size

2279 Views 23 Replies 5 Participants Last post by  KeepTheFeather
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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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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.
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... I need to remove the back wheel to remove the caliper from the rotor?
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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Get help from PARTZILLA (LIINK) diagram parts.
Check that all the parts are back in to their place. especially:

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.
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.
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.
Thanks man. I ended up removing it by drilling a small hole, then taping a triangular file into the hole and using an adjustable wrench to unscrew it. Was a majer headache and in definitely never making this mistake again!
Well done!!! You can practice the "feeling" of tightening task. Take a selection of nuts and bolts, lock the nuts in the clamps, and start to break the bolts. At the end you will understand what is that flexibility of the metal, and how not to tighten more than necessary. Then one day you will break a bolt again, and then you will remember that case, and that it was not so terrible, and that with a little creativity and a lot of patience, you solved the problem(y)✌🍾
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