Thread: BMW Airheadz
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otto_kretschmer otto_kretschmer is online now
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Join Date: Jun 2010
Location: Arizona
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BMW Airheadz

I rebuilt my 75 R90S engine a year ago. I put in the 286 cam and had the flywheel lightened.

The results is an engine that has noticeably more power but has a stumble when cruising around 40 mph with the throttle barely cracked open.

The stumble makes the bike annoying to ride so I want to fix it but I don't know if the real problem is the cam or the lightened flywheel.

I suspect the cam but the flywheel is a lot easier to replace. Cost wise its probably about the same, unless I find a used flywheel somewhere.

the jetting is slightly rich according to my KN air/fuel meter that I installed temporarily

any opinions?
Old 01-18-2013, 09:56 PM
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