I did the white spacer mod today. It turned out to be a Christmas gift to myself. I considered using 4 washers since 4 of them were smaller than the spacer, but I settled for three. Perhaps it was best I did. Maybe it's all in my head, but I get the feeling that it just runs better! It idled a little weird for a while, but when warm, I adjusted the idle mix, and I think it ran the best it ever has. SMOOTH. Don't get me wrong, on a good trip, the thing would get nice and smooth even running lean, but now it acts like a fuel injected car . SMOOTH--RESPONSIVE She's got some balls now! Seriously, goose her hard off the line, and she'll go sideways with ya' now . Maybe it's just differences in road conditions/driver input? Smooth, damp asphalt? Maybe its just all in my head?

Has anyone else noticed this kind of effect from just doing the spacer mod?

I noticed that using the enrichment knob when warm before the mod speeded up shortly before bogging on idle. The same is true or more true now. However, I did experiment and find that, though it ran rich at idle with the knob pulled, I got an increase in power with some throttle. I believe this means that the idle mixture is approximately correct, but the needle jet is still a little lean? Or, perhaps, since maximum power is produced by running a little rich, that... Hmmm...

Any ideas?

The thing still backfires, by the way.   Maybe a little less, especially when the engine is not fully warm. But it seems like when it does make noise, it is often moderately loud backfiring rather than gentle noises.

I ride between at least 1000-2000 feet elevation, typically. My house is around 1500. I live in hillbilly coal miner country, so I am liable to experience pretty wide elevation swings. In fact, I can't step foot onto asphalt without an elevation change . For cryin' out loud, hiking across our own property is an elevation change! Got plenty of acreage, if we could do much with it . Skin the turf, and watch your dirt wash away with the next rain . It's the curse of the mountains, I guess.

good you seem to have gotten the good out of the white spacer mod, I'll leave answering the questions to those who know the bike better than I

If, at WOT, you back throttle a tiny bit and the bike goes FASTER you have too small a main jet
you will feel this as a throttle drop surge, where the first few degrees of 'backing off' actually gives a tad more power
factory jetted Rebels are notorious for this

Art Webb wrote on 12/25/15 at 09:07:38:


And Savage/S40s!