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Post by mrpalmetto on Mar 15, 2015 13:48:47 GMT -5
If I'm running near full throttle and as I back off slowly near mid throttle, and as I continue to ease off, the RPM's raises and speed increases a little. What does that tell me about My main jet size?
When I am cruising at 55mph, and I'm revving at between 6800-7000 RPM range, is that a safe and reliable RPM?
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Post by JerryScript on Mar 15, 2015 13:58:59 GMT -5
That tells you that you are running lean. If you are idling fine, then try the next size jet up. You may need to adjust your needle clip after up-jetting the main.
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Post by mrpalmetto on Mar 15, 2015 14:44:32 GMT -5
Jerry.
I'm running a 115 in a 28 mm carb. Almost great idle. Does not sound perfect to me but its real darn close. Almost perfect. I had a 122 or a 125, can't see those numbers, in it before but I had to turn my air/fuel screw all the way home to get my best idle so that's where I changed to the 115 because that's all I had. Any suggestions to what size jet to try next? Thanks for your help.
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Post by JerryScript on Mar 15, 2015 19:42:27 GMT -5
I would suggest a 118, close enough to the 115 to adjust the a/f for a good idle, and hopefully large enough to richen it up at WOT.
Your RPMs are ok for that speed, but I personally would try to bring them down to the 5.5-6.5k range when cruising.
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Post by mrpalmetto on Mar 16, 2015 7:13:21 GMT -5
Very good. I appreciate you taking the time to post this info. It is very helpful to get good reliable info so quickly. Thanks.
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Post by geh3333 on Mar 16, 2015 7:45:28 GMT -5
The lower the rpm the better it is for the engine. The only problem with these small engines is that its hard to reach those speeds with lower rpms. Your right about where you need to be. For example at 7000 rpms I'm usually at 60mph and 7500 rpms 65+ mph . I try not to go over 8000 rpms and only keep her around 7500 for shorter distances. I ride between 6000 and 7000 80% of the time.
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Sophomore Rider
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Post by mrpalmetto on Mar 17, 2015 6:42:06 GMT -5
I changed my drive gears also. Do you have quick, decent or adequate acceleration.? From my experience the only thing that increases top end is the gears, because the engine is only going to go as fast as the gearing is going to allow. I may be wrong but, for example, belt size did nothing, and I guess there are a few mods that get you 1 or 2 mph, but with hills and wind and weather factors, it's really hard to tell?
Was it not the gearing that got you to that high a top speed?
Thanks for the good info on Rpms.
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Post by jerseyboy on Mar 17, 2015 7:08:10 GMT -5
Cruisin at 45-50 mph 6K rpm is perfect IMO..do you have a pipe and uni filter on that scooter? If so you may want to try a 120 just too see if it gets rid of the top end bog....Im sure it will  |
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Post by mrpalmetto on Mar 17, 2015 11:21:44 GMT -5
Yes, pipe and Uni. I have a 118 and 120 comming from Jets R Us. The 122 I have is too much.
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