xander450 Posted June 16, 2012 Report Share Posted June 16, 2012 As title says - just put together a serval 421, need to jet. I'm using a pair of VM32's, mostly just because they're what I've got around. I know they might not be ideal - let's skip the bit where we talk about why PWK 28's would be better. So, on to jetting - setup is: serval 421 w/ 24cc domes at 500ft, squish at .042", uni pod filters, stock timing, mixing Motul 800 at 32:1. Anyone got a ballpark on jetting? Thanks!! Quote Link to comment Share on other sites More sharing options...
guns4children Posted June 16, 2012 Report Share Posted June 16, 2012 Sell the vm32s buy 33pwks 48p 160m cel needle mid clip Quote Link to comment Share on other sites More sharing options...
ban565 Posted June 16, 2012 Report Share Posted June 16, 2012 VMs are way of the mark from jetting. Be prepared to go several jets from the stock jetting. I found this out jetting for a blaster. If your are going to keep them be prepared to spend a lot to get the jetting right. Quote Link to comment Share on other sites More sharing options...
xander450 Posted June 16, 2012 Author Report Share Posted June 16, 2012 Aren't the stock banshee carbs mikuni vm26's? Quote Link to comment Share on other sites More sharing options...
RadarRacing Posted June 16, 2012 Report Share Posted June 16, 2012 I dont mind those carbs. It seems like with the vm 34 carbs we ran about mainjets in about the 260/270 range. I would think the 32s would be a little smaller than that. All the VMs I have had needed the needle leaned out one or two clips from the middle. I would expect it to be in the low 200 range dor main but you might wanna start at 270 and only run it 50 or a hundred feet or so and keep checking it as you go down. 34mm mikuni flatslides I ran 250 mains. Quote Link to comment Share on other sites More sharing options...
xander450 Posted June 16, 2012 Author Report Share Posted June 16, 2012 Radar, was that jetting for a 421 serval? That seems way low - I tested for a short while this afternoon on 340 main/35 pilot with needle in the middle and it was definitely lean (and tested with leak down, motor is tight). Quote Link to comment Share on other sites More sharing options...
dirtydownunder Posted June 16, 2012 Report Share Posted June 16, 2012 with the 34tm radar speaks of with the 421 it doesnt. ive been trying to jet mine and i started at 350 and im at 280 now and its heaps better but not perfect i still need to drop a few main sizes. ive been scared to lean it but these carbs just dont need that much main. thats with the flat slides. radar, what dumps where you using ? 389 q0 -q2's ? Quote Link to comment Share on other sites More sharing options...
xander450 Posted June 17, 2012 Author Report Share Posted June 17, 2012 Anyone? I tested for a short while today at 440 main, 40 pilot - a bit lean which surprised me, that was my surely-too-rich guess. Next shot will be 480/50. Quote Link to comment Share on other sites More sharing options...
RadarRacing Posted June 18, 2012 Report Share Posted June 18, 2012 Holy cow. Those must have wierd slides or needles. Thats kind of the problem with oddball carbs. Usually a small carb like that was designed for some small or old dirtbike like a 125 or something. I dont know if I would mess with em if they seem hard to tune at all. Quote Link to comment Share on other sites More sharing options...
xander450 Posted June 19, 2012 Author Report Share Posted June 19, 2012 Perhaps you're thinking in keihin jet ranges? Stock jetting is in the low 200s. Plenty of ported stockers are running 300+ mains on stock vm26's. Quote Link to comment Share on other sites More sharing options...
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