I have the 165 mains that Dynojet recommends, and I suspected that they might be a tad rich based on driving around town here, but figured that it would really show itself in the mountains, so I took my jetting kit with me.
Sure enough, over Blewett Pass, I could barely manage 75mph when running up the last couple of miles to the summit.
When I got to Wenatchee (my brother's house to spend the night), I rejetting to 160s. Felt way better around town, and felt really good on the flats runing over to Idaho on Hwy 2 and I-90.
Coming back on I-82, as I approached Yakima and the temps started getting warm, I noticed that the stumbling was back when I'd crack her open just past the 3/4 throttle point. Sure enough, as I went over Chinook Pass, I really noticed the stumble at these throttle positions.
Once I got back down to Enumclaw (about 500' above sea-level), the bike ran strong again, with only a SLIGHT hint of the stumble, right around the 7,000 RPM mark at 3/4+ throttle.
SO, my question is this... HOW sensitive to altitude should these bikes be, and is it possible to jet to have it work well down here, and up there both? Seems like I might be compromising my "down here" performance to make it work well up there, and vice versa.
OR, is this a needle position thing, seeing as it seems to run strong RIGHT up to that 3/4 throttle point, even at altitude??
Interesting note... at the summit of Chinook pass... the idle dropped by about 300 RPM and it almost wouldn't start again... I suspect this is farily normal??
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