Crf cam specs

smitty418
Profile picture for user smitty418
Posts
7
Joined
1/1/2017
Location
Merrillville, IN US
smitty418
Edited Date/Time 3/31/2018 6:33am
I have rebuilt my 2010 crf250 with new head piston crank cam chain etc but it still doesn't run , has fuel spark . It will just pop out the exhaust like it's trying to run . I'm thinking the cam sprocket may have spun and messed up the cam timing ,does anyone have the cam specs ? I have access to a degree wheel and micrometer .
|
Paw Paw 271
Profile picture for user Paw Paw 271
Posts
3640
Joined
4/3/2013
Location
Benton, LA US
Paw Paw 271 3/23/2018 10:50am
3/23/2018 10:50am Edited Date/Time 3/23/2018 10:51am
Are you 100% sure you are using the correct timing mark on the crank gear? With the marks lined up, is the piston at TDC? If not then the incorrect mark is being used.
Yes the cam gears can slip on the cam. Many post about this.
Sorry I don't have the spec's for the cam.

Paw Paw
jonboy688
Profile picture for user jonboy688
Posts
438
Joined
9/3/2015
Location
China Grove, NC US
jonboy688 3/23/2018 2:04pm
3/23/2018 2:04pm
pull the plug and make sure the piston is tdc, and make sure the cam lobes are racing up on the intake side
smitty418
Profile picture for user smitty418
Posts
7
Joined
1/1/2017
Location
Merrillville, IN US
smitty418 3/23/2018 4:13pm
3/23/2018 4:13pm
jonboy688 wrote:
pull the plug and make sure the piston is tdc, and make sure the cam lobes are racing up on the intake side
That's how it's sitting in there at the moment . Is it safe to skip a tooth forward or back to test if the cam has spun ?

The Shop

See All »
Paw Paw 271
Profile picture for user Paw Paw 271
Posts
3640
Joined
4/3/2013
Location
Benton, LA US
Paw Paw 271 3/23/2018 4:28pm
3/23/2018 4:28pm Edited Date/Time 3/23/2018 4:29pm
jonboy688 wrote:
pull the plug and make sure the piston is tdc, and make sure the cam lobes are racing up on the intake side
smitty418 wrote:
That's how it's sitting in there at the moment . Is it safe to skip a tooth forward or back to test if the cam has...
That's how it's sitting in there at the moment . Is it safe to skip a tooth forward or back to test if the cam has spun ?
I would not do that. If the gear has slipped, then you may make contact with a valve to the piston and start another problem.
Did you check to see if the piston is at TDC with the marks lined up?

Paw Paw
flomiester
Profile picture for user flomiester
Posts
188
Joined
2/10/2012
Location
Elwell, MI US
flomiester 3/31/2018 6:33am
3/31/2018 6:33am
Put a dial indicator on your intake bucket and line up your tdc mark on your ignition during overlaop the intake should be around .082" with .005 lash if your cam has spun it will be a lot less lift i graphed almost every cam honda has made since 2003 and usally took a TDC lift number .

Post a reply to: Crf cam specs