I have run 90/1 in my 2011 tr280i and switched to 130/1 with this season being my second.No problems whatsoever.Loaded my gear up this past sunday and didn't take my daughters TY175 because she was away.After a good warmup and a couple of loops i stopped to top up.Ooops....i topped up with the TY's 32/1 premix

 But ya know what? It ran perfect.Not really any smoking that i could notice.Starting was the usual 1st kick.But it did smell funny because of the Ipone strawberry scent.

Edited November 29, 20169 yr by ric h

Interesting I don't think the pre mix ratio is quite as critcal as some say.

 

I've heard some pretty lean ratios up to 140.1

 

In the SSDT all bikes get supplied 50.1 certainly mine ran fine,maybe a fraction less crisp but nothing that would bother anyone.

 

Normally run 100'1 myself.

 

Issue I would think is the build up of oil in the exhaust over a period of time. 

Timely topic.  I have a 2012 Explorer and want to run 80:1 as I have another trials bike...sounds like the answer is: "no problems"  (only run 100:1 so far)