[Simplyorange]

after sinking my bike, we have determined that the clanking noise is the piston walking in the cylinder due to the ring being washed away. my question is, can i bore the cylinder to an oversized piston like i have done to other bikes because i was told it may be chrome lined and has to be replaced. im asking because i cannot find any oversized pistons,all of them are standard bore high compression.and if i can bore it i want to find out what dimensions i need to bore it to to accept a piston.

 

[09RappySE]

Yes you can bore your cylinder, your cylinder is nikasil coated, and it can be re-coated after bore, I would call CP pistons and inquire about a custom piston if there are none out there.....you could probably use a raptor piston and machine the valve reliefs if needed. Bo would know.

 

[Simplyorange]

they say at honda that it is not nickel coated and can be bored .25 over, for $278 i can buy a new cylinder, and i can find new pistons in the stock bore size much easier. are you positive it is nickel coated?

 

[D Bergstrom]

Thumper Racing makes a big bore kit:

http://thumperracing.net/index.php?route=product/product&path=37_41_100&product_id=91

They do not mention that the cylinder needs to be replated after boring, so that makes me think it is not plated. Does the stock cylinder have a steel sleeve? Its bore can't be all aluminum, the aluminum won't hold up without being plated. I have not had my engine apart yet to know, but I would think someone on here has and should be able to give you the correct answer.

Doug

 

[Simplyorange]

im not looking for big bore, im looking to get rid of scarring if there are any, but i just had a buddy of mine bet money that my piston is fine and that my clutch basket beraing is bad, makes since because i found out honda did a bearing revision recently.

 

[D Bergstrom]

im not looking for big bore, im looking to get rid of scarring if there are any, but i just had a buddy of mine bet money that my piston is fine and that my clutch basket beraing is bad, makes since because i found out honda did a bearing revision recently.

Well, you have to bore the cylinder no matter what. If you are going to buy a new piston and bore the cylinder, might as well go big bore and pick up some more power. Regardless if you bore it 3 mm or .25 mm, it is going to cost you close to the same when all is said and done. If I have to spend money, I would rather spend it knowing I will pick up a little power then just replace with stock parts. Just my opinion.

I do agree with your buddy though, I don't think it is your piston clanking.

Doug