I installed the Mistral high pipe and found as others have reported that it touches the bottom of the turn signal. It's probably not a problem, but I thought it might improve the look to try some different rear turn signals anyway.
I found these inexpensive black steel bullet turn signals on Amazon, and they worked out better than I expected:
[You must be registered and logged in to see this link.]They are actually pretty high quality solid steel, strong pieces, and the look matches the bike nicely I think. They are very bright too, so they don't compromise safety.
Here's a pic of my bike with the Mistral pipe and the new turn signals; you can barely see it at the top of the pipe, it's pretty small.
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