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35
Joined
10/11/2025
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WEST MEMPHIS, AR
US
I'm planning on doing a top end rebuild on my 2005 Cr250. I'm not sure to go with Wossner, Wiseco, or OEM. What gasket kits are known to be good? I currently have
Maxima Assembly Grease, BikeMaster Scraper Set, HP Tools Premium Digital Caliper,
Motion Pro Torque Wrench Adapter, BikeMaster Feeler Gauge Set, and telescoping bore gauges in a cart. Anything that I need for a top end rebuild? What all do I need to check my squish? I already have a torque wrench and a service manual.
I'd use OEM gaskets.
You need 0.06 - 0.08" (1.5 - 2.0mm) solder and your caliper to measure squish, if the squish is larger than the solder, twist the wire to make it larger. The squish is typically 0.075 - 0.082" (1.9-2.1mm) when new, 0.043 - 0.47" (1.1 - 1.2mm) is ideal.
I was 11 years old when I did my first top end on my 1981 YZ 80. Rings only and dad was supervisor.
I'd stick OEM gaskets and hard parts for your rebuild. You'll need some HT Hondabond to seal the RC valve assembly to the front of the cylinder after you de-carbon the valve and the exhaust port.
Isn't there a gasket for the RC valve cover or are you referring to something else? I plan on using oven cleaner on the exhaust flap. What about drilling holes for the exhaust bridge? I'm kind of nervous drilling on the piston.
The Shop
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@JMCR250's referring to the RC valve assembly, it's sealed with 4 o-rings and high temperature silicon (HT Hondabond)...
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