I'm late to the party here, I have a 2012 with a Guhl reflash which I liked for the low end power add. I do still notice a huge clunk when I transition from off to on throttle. My bike sees redline a fair amount, so I am interested in the big hp increase, also for the smoothness and especially for the mileage increase, my bike seems to get very bad *ahem* mileage. My brother has the same bike and is on here sometimes, he loves it and swears I should get it and he knows I have the Guhl flash.
But one thing I saw and I only saw it once, was that somebody said you can run 89 octane with Steve's flash? I only saw that once and mine sees WOT at low rpm so I notice that would make for a lot of detonation if the octane was too low. That's not something I would want to risk unless I was pretty sure it was ok, so that's what I am looking for here.
So what's the deal, can you run 89 with this or what? Between a mileage increase and the price delta between 89 and 93, this thing could help pay for itself.
Thanks
I'm thinking I am the best to answer here. Yes, I built the flash on 89 octane, on purpose, it was done so that if the various tuning parameters would work with 89, higher octane, 91-93 just adds a margin of safety, so I suggest that a person follows the recommendation of 90+ octane from Kawasaki.
Also, the issue of wOT at low rpm is important . Obviously there's a pretty large difference in load between wot / 1st gear 3k rpm, and 6th gear, 3k rpm. So to just say the issue is WOT low rpm doesn't really provide enough info. Regardless, I know there's somebody out there who will pull WOT at 2000 rpm in 6th gear, so yeah, I did it while tuning repeatedly to be sure there's no gas knock. Do I think it's a good idea on any engine? No. Do I recommend it on a stock tune? No. Do I recommend it with my tune? No. High cylinder pressures at low rpm and high load is very tough on the engine regardless. But the fact is I did allow for that while building the flash, and I did back off some parameters to be sure there was no detonation, on my bike, with 89.
All that said, WOT at low rpms high load will just never be a good idea... that's what a gearbox is for. Steve