Hey there
Lots of talk around the KA100 and peoples experience with there reliability and tuning them, now that the VLR package has been around for a bit interested in what people are seeing with them. I’ve noticed that IAME’s manual is fairly informative compared to the Vortex one and information around tuning is limited. Are people just applying KA100 settings to the VLR and seeing a good response? Thinking around Fuel/Oil Ratios, carb tuning H/L settings, plugs
George – Short answer, yes, I’m using the KA manual (which is light years ahead of the VLR. See my post somewhere on the forum where I whined about it earlier). The VLR manual will tell you to mix oil and fuel at 40/1. EVERYONE says you’ll basically blow up your engine with that diluted mix. I’ve had 6 to 7 oz oil per gallon recommended by several competent sources – which is 20/1 + or -. As to plugs, the recommendation in the manual (e.g., B10EG for hot weather) works fine. It is my understanding that it is required for “sanctioned” races, although an Iridium BR10EIX can usually be used in club racing and is a “better” plug. As to jetting, it is my understanding that is a bit of an art – experienced drivers tune by ear as they are driving. I’m nowhere near that skill level yet, having come from the Rotax world. For your reference, I have NEVER heard of a lean setting less than 3/4’s turns out and a rich setting never more than 1 1/8’s turns out. “They” say to tune the low speed jet first (the one closest to the engine) and then adjust the high speed jet. Hope this helps.
Thanks Steven, we have been seeing the same thing around oil/fuel mix and aiming for 20:1. The engine seems fairly solid and haven’t had any issues as of yet. interested to hear about your maintenance schedule your following.
Hi George – My engine only has about 3 hours, so “maintenance” is not yet on my radar. I did check the head and exhaust bolts after breaking it in. Everything I read focuses on way too early (to me) removing the carb, draining it, breaking it down, replacing soft parts (diaphragms, etc.) and pressure checking the “pop-off”. I don’t yet have a pop-off valve to check my carb, although I will eventually buy one. I’ve not yet found anything that tells me what to do if my pop-off values are incorrect, that is, what do I do about it? My engine seems to run well on our momentum track in Tucson – 14,800 to 15,000 max RPM’s, 8,800 to 9,100 low RPM’s with a stock 10 tooth front sprocket and a 74 tooth rear.