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Aftermarket cam break-in

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I just recently purchased a Stage 1 cam by HotCams for my 125, and I'm wondering if anyone out here knows what the recommended break-in procedure is. I thinking once it arrives, hopefully, this info will be included with the cam.

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When you install the cam, make sure you use some moly paste on the cam lobes. On your machine you shoild replace the rocker arms and keep your old rockers with your old cam as a 'set'. Change your oil before starting the engine with the new cam.

Once you have everything installed and valve clearance set to spec, start the machine and adjust the idle speed up to 3500-4000 RPM. Let it run at the fast idle for 5 minutes. Have a fan blowing air on the engine so it doesn't overheat. Stop the engine, let it cool down, and check for leaks, etc. Repeat this procedure for 10 min. Let the engine cool completely and check the valve clearance and change the oil again (to remove any traces of moly paste from he engine).

Ride it and have fun!

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On the hotcams card, it tells you what they recommend.

Don't let it idle much, and they suggest going on a gentle ride for 10 minutes. Then, re-adjust the valves after the engine is cold.

The valve lash may be different. It is the same on CRF 450's, but different on XR650's, so I don't know for sure.

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Correct. You don't wan't it to idle at low RPM's. Low RPM's allow the rockers to 'hop' on the cam and won't allow a proper work-hardening to develop on the surface. The elevated idle (3500-4000 RPM's) accomplish the same thing as 'riding gently for 10 minutes'.

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cool, that is basically what I figured. be sure to lube up the lobes and specified areas of rocker arms with a molybdenum sulfide assembly lube, as well as engine oil on bearings etc. followed by mellow riding (low RPM 3000-4000ish) for the first few hours, don't romp on it. change the oil after that first little break in period, and I've heard that you would want to use a conventional oil on the breaking in process as the synthetic actually lubricates too good. don't know how much truth there is to this, but I was gonna do it anyway. I've been running Amsoil synthetic motorcycle oil normally and will after I break it in. thanks for the info guys, i appreciate it.

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On your machine you shoild replace the rocker arms and keep your old rockers with your old cam as a 'set'.

one other question, how critical do you think is replacing the rockers? I didn't think about this, nor did I plan on, or budget these parts in at this point. but it definitely makes sense to have both of the two surfaces new in order to achieve proper mating of the contact areas of the cam lobes & rocker arms

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I've put in a dozen or so Hotcams, and never replaced rockers or used magic lube. Just drown the cam lobes and journals with whatever oil you are running in the bike, and ride it.

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one other question, how critical do you think is replacing the rockers? I didn't think about this, nor did I plan on, or budget these parts in at this point. but it definitely makes sense to have both of the two surfaces new in order to achieve proper mating of the contact areas of the cam lobes & rocker arms

Well....in a perfect world, they should be replaced. I would say it's less of an issue on your bike because of the relatively low seat pressure.

If this was a high-end performance rebuild, it would be a little more critical.

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I've put in a dozen or so Hotcams, and never replaced rockers or used magic lube. Just drown the cam lobes and journals with whatever oil you are running in the bike, and ride it.

since you've had quite a bit of experience with these cams, I'm wondering along with what other mods you've done with this cam, how much better performance did you notice after installing them. thanks

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The hotcam, just to pick a brand that is currently being discussed, is probably the best bang for the buck in performance increases, next to gearing. Nothing will beat a $15 front sprocket change.

Since engines are air pumps, increasing the entire system's ability to flow more air usually results in more improvement than a single change. Sort of a package approach. A higher compression piston, especially at high altitude where I live, coupled with a hot cam, can be a very big improvement. I don't consider jetting or uncorking to be a change, since I've never owned a corked or poorly jetted bike.

Exhaust changes are pretty low on the scale of performance gained per dollar spent. If we were honest with ourselves, we really do it for the cool looks, the manly rumble, and the bling effect.

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so as far as front sprocket upgrade I assume you are talking about going from a 13 to 14 tooth sprocket?

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