02 CR 250 Topend Questions

[Sawblade]

I’m doing my first top on my 02 CR 250 and have two questions. The first I think is obvious but want to clarify where the owners manual is vague.

For the RC value the manual says to remove the socket bolt and stopper plate. Then remove the valve shaft assembly and flap valves from the cylinder. This is done after removing the cylinder from the cases, correct?

Is there clearance to remove the cylinder with the head on?


Thanks,
Sawblade

 

[NO HAND]

I always disconnect the cables from the rc valve before removing the cylinder off the crank cases. You don't need to remove the flap valve from where it is, just the cables is enough. You'll see these cables are a pain to remove and the manual isn't helping much in regards to the rc valve. You can leave the head on no problem. Just remember to remove the gas tank and preferably the radiators.

 

[Sawblade]

I always disconnect the cables from the rc valve before removing the cylinder off the crank cases. You don't need to remove the flap valve from where it is, just the cables is enough. You'll see these cables are a pain to remove and the manual isn't helping much in regards to the rc valve. You can leave the head on no problem. Just remember to remove the gas tank and preferably the radiators.

Thanks No Hand. I removed the RC cables, tank and radiators last night. It was late, so I wanted to be sure before pulling the jug.

Thanks again.

Sawblade

 

[Sawblade]

How to remove the flap valves from the cylinder?

Ok, I have the topend off and have removed the valve shaft assembly. How in the hell are you suppost to remove the flap valves from the cylinder? Ive tried turning them as much as possible, but no dice. Its apparent they will not come out the exhaust and will have to be removed through the exhaust port, I'm I correct? Do the flap valves even come out?

At this point I’m so frustrated I may very well go back to Yamahas! :|

 

[Dragmeistr]

Yes, they will have to be removed through the exhaust port and not through the front of the cylinder.

 

[Sawblade]

Yes, they will have to be removed through the exhaust port and not through the front of the cylinder.

Thanks Dragmeistr. Can you describe how to turn them so they drop out. After sleeping on it I wonder if there is just enough carbon build up causing my difficulties in removing the flap valves. :think:

 

[bedell99]

Hello Sawblade,

I would assume you removed the shaft from the power valve. The power valve flaps actually slide out quite easily out of the exhaust port once the shaft is totally removed. Take a good look at this schematic.

http://www.servicehonda.com/hard parts/off road/cr250 2002/cr250 02 frames page.htm

If they don't fall out, you are right they are built up with carbon. Not good. Take some over cleaner and spray it on a metal brush and start cleaning. This will probably take a while. make sure you wash the cylinder ever 5 minutes with water to prevent corrosion. Good luck and keep us updated.

Erik

Erik