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Discussion Starter #1
i have the very common scoring cylinders on cbr 954 2003 year build
i hope can someone help me to find an answer to my questions
a) what kind of aluminum is the cylinder/bores made of will tht be pure alusil or something else??
b)if i oversized to 76mm means to increase compression 13.2:1, 13.5:1 will that be safe in a long run after xx,xxxkm?
people complains of knocking etc
c)what do you think will be more reliable/durable for the engine nicasi or just honing/glazing existing surface, if it is alusil
d)for b topic will be best the wiseco or je pistons, forged. what about for topic c what kind of pistons,rings you suggest?
could oem be restored whit some kind of coating and a new set of piston rings?


how far can i go with honing glazing alusil?
 

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I'm not familiar with the 954 per se but I am familiar with engines. If your cylinder walls are scored and the engine is not running smooth it will need a rebuild. We know that the bore & stroke is 75x54mm. Depending on how bad the scoring on the cylinder a machine shop will probably recommend up to a 1mm over bore. Meaning, the new bore would be 76mm. That means you have to buy a 1mm overbore piston kit it's that simple.

I'm sure you will find a piston kit with different compression but I would try to stick close to stock compression. I would take the engine off the frame and consult with a machine shop. They can put a scope inside the cylinder and see the condition. As they take the engine apart they will see what's in spec and what's out of spec. Who knows you might need oversize/undersize bearings.

I don't know your budget but a machine shop might charge $1-2k depending on what needs to be done and that number can also double. If you keep it basic I'm sure it will be under $2k.

You mentioned about Nikasil or some kind of Nickel coating on the cylinder wall those things can be honed or re plated depending on the severity of the scoring. My CBR300 has nikasil. I'm not sure if our Fireblade engines are built with cast iron or Aluminum liners...maybe aluminum so you probably just need the block bored out 1mm.
 

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Broadly agree with above. They are alusil bores, so only boring and honing required. The honing is tricky, needs a honing machine with a short stroke, if you can't find one local to you I know a good firm in germany, they did my 929. But before you do anything, have you still got good compression and low oil consumption? Maybe you don't need to do anything, the bores on 929s and 954 are always scuffed, and piston slap is not the end of the world unless it doesn't go away when the engine is warm.
You can of course try Nikasil but results are variable and the last thing you want is for the plating to flake off. It has happened.
I used JE pistons 12.5:1 but found the holes in the oil ring groove were inadequate , causing high oil consumption (the oil wasn't getting scraped away ) so had to increase the size of the holes and drill more. If I did it again I would try Wiseco.
 

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Broadly agree with above. They are alusil bores, so only boring and honing required. The honing is tricky, needs a honing machine with a short stroke, if you can't find one local to you I know a good firm in germany, they did my 929. But before you do anything, have you still got good compression and low oil consumption? Maybe you don't need to do anything, the bores on 929s and 954 are always scuffed, and piston slap is not the end of the world unless it doesn't go away when the engine is warm.
You can of course try Nikasil but results are variable and the last thing you want is for the plating to flake off. It has happened.
I used JE pistons 12.5:1 but found the holes in the oil ring groove were inadequate , causing high oil consumption (the oil wasn't getting scraped away ) so had to increase the size of the holes and drill more. If I did it again I would try Wiseco.
Wiseco is always a wise choice. 2 wheels or 4.👍🏻
 

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Discussion Starter #5
I'm not familiar with the 954 per se but I am familiar with engines. If your cylinder walls are scored and the engine is not running smooth it will need a rebuild. We know that the bore & stroke is 75x54mm. Depending on how bad the scoring on the cylinder a machine shop will probably recommend up to a 1mm over bore. Meaning, the new bore would be 76mm. That means you have to buy a 1mm overbore piston kit it's that simple.

I'm sure you will find a piston kit with different compression but I would try to stick close to stock compression. I would take the engine off the frame and consult with a machine shop. They can put a scope inside the cylinder and see the condition. As they take the engine apart they will see what's in spec and what's out of spec. Who knows you might need oversize/undersize bearings.

I don't know your budget but a machine shop might charge $1-2k depending on what needs to be done and that number can also double. If you keep it basic I'm sure it will be under $2k.

You mentioned about Nikasil or some kind of Nickel coating on the cylinder wall those things can be honed or re plated depending on the severity of the scoring. My CBR300 has nikasil. I'm not sure if our Fireblade engines are built with cast iron or Aluminum liners...maybe aluminum so you probably just need the block bored out 1mm.
Thanks T-bares will agree regarding stock compression but is very difficult to find pistons 11.5:1 76mm or 75.5 doesn't seems to be any choices unless is custom and wiseco will charge a fortune
Forgot to mention that engine is apart i bought the bike with a damage and when i brought it home the day after i took it apart i have disassemble the engine damaged lower crank case, crank shaft, connecting rote piston in cylinder 3 has a big damage cylinder is ok the connecting rode broke under piston
at this point i have bought used parts but will need pistons and i am on tight budget .......
 

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Discussion Starter #6
Broadly agree with above. They are alusil bores, so only boring and honing required. The honing is tricky, needs a honing machine with a short stroke, if you can't find one local to you I know a good firm in germany, they did my 929. But before you do anything, have you still got good compression and low oil consumption? Maybe you don't need to do anything, the bores on 929s and 954 are always scuffed, and piston slap is not the end of the world unless it doesn't go away when the engine is warm.
You can of course try Nikasil but results are variable and the last thing you want is for the plating to flake off. It has happened.
I used JE pistons 12.5:1 but found the holes in the oil ring groove were inadequate , causing high oil consumption (the oil wasn't getting scraped away ) so had to increase the size of the holes and drill more. If I did it again I would try Wiseco.
and here is the catch with CBR 954
the cylinder bores are made of aluminum powder mixed with ceramic and graphite, not sure if this is alusil, this information is official from honda, what i believe thought it must be some kind of coating the above because honda advice in case of scoring depends how deep is until 0,25 and also provides oversized pistons 0,25
so if scoring is deeper, honing to 76mm would have to go for after market pistons and plaiting ib nicasil, no other choice
when i contact wiseco in Europe they said that the main problem why scoring happens is because of the big clearance in the bores which develops slap and then scoring, he mentioned that he would probably suggest 0.15 clearance
now question is: is there possibility in Germany somebody to do this kind of coating with ceramic and graphite, or anyother possible coatingon aluminum, not the nicasil
also if i will increase the compression to 13.5 what could be the downside, how about the cam shaft?
if glazing the bores could you please advice, if you know, of which brushes should be done with? they should know but just for cross info
Many thanks for offering to help me with the machine shop, maybe, will let you know
 

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Thanks T-bares will agree regarding stock compression but is very difficult to find pistons 11.5:1 76mm or 75.5 doesn't seems to be any choices unless is custom and wiseco will charge a fortune
Forgot to mention that engine is apart i bought the bike with a damage and when i brought it home the day after i took it apart i have disassemble the engine damaged lower crank case, crank shaft, connecting rote piston in cylinder 3 has a big damage cylinder is ok the connecting rode broke under piston
at this point i have bought used parts but will need pistons and i am on tight budget .......
I don't know how tight your budget is but if you want to keep the cost down I suggest finding a used motor on eBay or online that can ship the motor to your home. Then, all you have to do is buy a $150 rebuild kit with all the seals the freshen it up. A used motor should last a while if maintained well.

Rebuilding the engine you have now will require more money up front. A damage crankshaft will require removing material to repair it, then for sure you are getting new size bearings. It's been a decade since I've taken apart an engine but do you have a bore gauge, micrometer, feeler gauge and all the typical stuff to check the specs?

Maybe just have the head rebuilt for now it should cost about $350 depending on what it needs.
 
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