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SM base gasket swap?

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I'm going to put a new E model base gasket on my 08 SM. I have a E model intake cam on now and I'm going to put an E exhaust cam when I do I will put the E base gasket on.

The question is...do I have to get the cylinder re-honed and new rings put on? I'm sure it will need to be broken in again right? Thanks for the time.

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doing the base gasket is not worth your time and money ... your only looking at 0.5 HP gane

now if you are doing a BBkit ware you have a good reazon to pope the cylender off than do it

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i would wait to do the e-model base gasket till your ready to put on a BB kit.the little bit of extra hp isint worth it for all the work required.if you do end up doing it then you wont need to rehone the cylinder.just clean it up with a ball hone(about 10 sec)and put new rings on

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Yeah don't do it unless you are pulling it for some other reason.

If you do it anyways, no you don'thave to re-ring it unless you pull the piston out of the cylinder. Just pull the jug up enough so that you can see the wrist pin and pull the circlip out and then pull the wrist pin.

Make sure you replace that circlip and put some assy lube on the wrist pin and cams when you re-install.

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Thanks for the info. I am definetley going to do because the exhaust cam will cause me to lose some bottom end. The increase in CR makes up for it. Hence the e model having the thinner base gasket.

Also, by bike was a demo model and uses a little bit of oil. I got it with 500 miles on it and I'm sure it wasn't broken in properly. So repacing the rings and starting over is not a bad idea right? But to properly seal the new rings should I re-hone or just ball hone as you recommended?

Thanks again for the help.

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No need to hone the hard plated cylinder. You should replace the rings if you pull the piston out. Eddie recommends the dry assembly so the new rings seat right in.

If the bike is well broken in, running well and low miles, you can do what Capt. Uno recommends and I did - pull the piston pin clip, slide the small end pin out and remove the cylinder and piston together as a set. That way the rings never leave the cylinder and there is no need to replace them. Replace the removed piston pin clip with a new one and you are good to go. In your case it sounds like the rings never seated too well, so you want new rings.

Put a rag under the cylinder either way when you remove it. Ya don't want to drop a piston pin clip into the bottom end. Since you are pulling the head anyway and replacing the rings anyway, you might as well do the base gasket mod. It is not that much more work if the head is off. If the head was not coming off, I would not bother.

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