Exhaust Bridge on CR250

[02'Cr Rider]

I'm doing my top end on my 02'CR 250 with a wiseco piston.Is it a good idea to drill holes out for the exhaust bridge on piston ? Will it be ok if not drilled out? Never had a bike with an exhaust bridge before.

Thanks:think

 

[Durt Cycler]

Get the holes drilled! If you don't you risk the chance of loss of lubrication there which leads to metal/metal contact and will cause the platings to flake and wear also have ring damage. I decided to not mess my piston that needed holes drilled so I took it to my local shop that I'm in there so much they drilled the holes for me for free. Ask then it shouldn't cost too much if your afraid to do it yourself. :)

 

[02'Cr Rider]

Thanks for the info Durt.I took out stock piston and it had no holes for lubrication.So I decided to drill them myself per wiseco instructions.Came out nice with drill press.

Thanks;)

 

[Durt Cycler]

Yea I noticed that too my stock piston had no exh. bridge lubing holes :scream: Luckily my topend took a crap and seized so I got a awesome '95 cyl. with PC porting! It was odd to see the OEM piston had no holes, Vertex piston had no holes (one I had drilled), but yet those good guys at Wiseco had them! :)

 

[NO HAND]

It's very important to drill the holes for Hondas because they have lousy tolerances on the bridge specs. It is supposed to be relieved 1.5 thousandth. and the bridge on my 00cr125 cylinder was not relieved at all. It made for such bridge marks on the piston even with the lubricating holes. At least it held until had it punched to 133cc, and when I sent it to Eric Gorr, he relieved the bridge like it should.