hi guys ive recently changed my italjet formula 50 from a 50cc to a 70cc and to be honest i cant see the difference with the extra 20cc any help to tune it up? ive changed the jet to allow more fuel to go through theres a 0.7 in at the moment im not sure what to do any help please?
have a read...........http://www.scootershack.co.uk/viewtopic.php?f=8&t=19172 will post some more tomorrow. http://www.scootershack.co.uk/viewtopic.php?f=8&t=16238
what top speed are you getting, and what other parts have you changed? I fitted the kit and due to running it in initially, I couldn't tell the difference, but as the weeks passed and I added other tweaks, the difference was huge. Mine will hit 55 on any road, hills at 40, and favourable stretchs I have seen over 65. And I am 17 stone plus and have a top box on the back, all which doesn't help. For me the top speed was not important, it's a town runaround, rarely sees 45, but I wanted a quick pull away and quicker 0-30. The sport kits are tough on the plus side but are low revving, and do produce extra bottom end power, which you can exploit by changing the transmission, namely variator,clutch, contra spring and belt. If you are on a budget I would advise changing the variator, or at least experiment with roller weights, mine preferred lighter weights, until I changed the contra spring for an uprated one. Also I am using the standard air box. I can't afford for the bike to conk out in the rain with a sports filter. The exhaust, I made a mistake, as there really isn't any premium ones for our bike, yes there is the zx tt and whatever, but in the tuning world they are less than best. What I will do in the future, as I have four pipes, three spare, is buy one that fits the engine and modify it to fit my bike, even if I have to ditch the centre stand. If you are running the standard 12mm carb, I found an upgrade from 54.5 to 60 gave me the best results with my kit, even a 62 made a difference of robbing some top speed and acceleration. I did try a 70 to begin with, but couldn't get it to run, so went down in increments until I settled at 60 on that carb. Can't really comment further, until you share your set-up.
Guns knows about trial and error :good: i also found the correct jet for my set up pretty much by using the same method, and yes i also found having a jet just 2 sizes too big gave a decrease in performance which was noticeable, just the same as having rollers just 0.25g too heavy or light made a noticeable difference The trouble is people will spend hundreds of pounds bolting pipes and exhausts and carbs and variators onto their scoots....but wont spend an afternoon with a jet box and a roller box fine tuning the set up :glare:
