My 2012 crf250r has 48 hours on it and I am planning to have a new piston put in it before 55 hours. I want to keep it at the stock 13.2:1 ratio. Should I stick to OEM or is there another company that makes a better piston? I plan on ordering the parts and then giving them to a mechanic to replace. Do I also need to order any gaskets? Does 55 hours sound about right for a faster C rider? Is there anything else that should be checked engine wise while it is open? Thanks for any help.
Best piston kit for 2012 and when to replace?
Started by
crf250rrider
, Jul 23 2012 11:29 AM
11 replies to this topic
Posted 23 July 2012 - 12:13 PM
crf250rrider, on 23 July 2012 - 11:29 AM, said:
Do I also need to order any gaskets? Does 55 hours sound about right for a faster C rider? Is there anything else that should be checked engine wise while it is open? Thanks for any help.
You will need a head gasket, cylinder gasket and the gasket for the exhaust head pipe.
You're going to get many different views on when to change out a piston but 55 hours sounds good to me.
You should check the valve clearances, it will literally add 30 seconds to the re-build.
Posted 23 July 2012 - 02:11 PM
XXxxXXxx, on 23 July 2012 - 12:13 PM, said:
You will need a head gasket, cylinder gasket and the gasket for the exhaust head pipe.
You're going to get many different views on when to change out a piston but 55 hours sounds good to me.
You should check the valve clearances, it will literally add 30 seconds to the re-build.
You're going to get many different views on when to change out a piston but 55 hours sounds good to me.
You should check the valve clearances, it will literally add 30 seconds to the re-build.
Ok thanks I will order those gaskets when I order the piston. I will tell the mechanic to check the valves also. He normally charges $175 to swap pistons and checks the valve while he is in there.
Posted 30 July 2012 - 11:43 AM
crf250rider,
The CP piston is just a real high quality. You're about the same speed as me and I ran an OEM piston in my bike for a good 60-70 hours before I replaced it. OEM will be just fine.
Assuming you don't need any head work you can always swap the piston out yourself. It's not too hard. Assuming you have the right tools (and have to make that one special tool, or just use a pocket screwdriver and vicegrips) you can do a top-end in an afternoon. I'll try to track down down a step by step guide I use (I'll gomx it to you) and just use the owners manual and it's easy.
The CP piston is just a real high quality. You're about the same speed as me and I ran an OEM piston in my bike for a good 60-70 hours before I replaced it. OEM will be just fine.
Assuming you don't need any head work you can always swap the piston out yourself. It's not too hard. Assuming you have the right tools (and have to make that one special tool, or just use a pocket screwdriver and vicegrips) you can do a top-end in an afternoon. I'll try to track down down a step by step guide I use (I'll gomx it to you) and just use the owners manual and it's easy.
Posted 30 July 2012 - 11:53 AM
CRF rider, on 30 July 2012 - 11:43 AM, said:
crf250rider,
The CP piston is just a real high quality. You're about the same speed as me and I ran an OEM piston in my bike for a good 60-70 hours before I replaced it. OEM will be just fine.
Assuming you don't need any head work you can always swap the piston out yourself. It's not too hard. Assuming you have the right tools (and have to make that one special tool, or just use a pocket screwdriver and vicegrips) you can do a top-end in an afternoon. I'll try to track down down a step by step guide I use (I'll gomx it to you) and just use the owners manual and it's easy.
The CP piston is just a real high quality. You're about the same speed as me and I ran an OEM piston in my bike for a good 60-70 hours before I replaced it. OEM will be just fine.
Assuming you don't need any head work you can always swap the piston out yourself. It's not too hard. Assuming you have the right tools (and have to make that one special tool, or just use a pocket screwdriver and vicegrips) you can do a top-end in an afternoon. I'll try to track down down a step by step guide I use (I'll gomx it to you) and just use the owners manual and it's easy.
Ok thanks a bunch. I will just stick to OEM and have it replaced within the next month or so. I think I will take it to somebody though. Im terrible with working on bikes and still dont even know how to check the valves. Im just worried I will screw it up some how and have a high repair bill. I'll have to ride with you at ACP some day. I read on gomx you go up there a lot. The track looks super sick now its just the drive up there kills it for me.
Posted 30 July 2012 - 07:52 PM
crf250rrider, on 23 July 2012 - 11:29 AM, said:
My 2012 crf250r has 48 hours on it and I am planning to have a new piston put in it before 55 hours. I want to keep it at the stock 13.2:1 ratio. Should I stick to OEM or is there another company that makes a better piston? I plan on ordering the parts and then giving them to a mechanic to replace. Do I also need to order any gaskets? Does 55 hours sound about right for a faster C rider? Is there anything else that should be checked engine wise while it is open? Thanks for any help.
Just my advice. Head gasket, base gasket, exhaust head pipe gasket, and timing chain tensioner gasket. If you are changing the piston out every 50-55 hours stick with the oem piston. As suggested already replace the timing chain as well. I build modified 250F's and we still run the stock piston in a lot of the applications and have never had an issue. Unless your moddifying the engine and increasing the cylinder pressure theres no reason to go with an aftermarket piston especially as a C level rider/racer. If your mechanic is only charging you $175.00 to do a top end including checking and adjusting the valves thats a great price.
