jrsunt Posted February 5, 2004 Report Share Posted February 5, 2004 I've been racking my brains all morning on this one. On a Gas Gas 280 pro raga replica, there is just too much top end power, what i mean is from nothing to 2/3 throttle the power is fine, nice and linear, offering plenty of manageable grip, the problem starts when using the top end, last 3rd of the throttle, the power seems very lumpy, it tends to come in all of a sudden, very good for dry conditions but not good for slippery english sections. I am running out of ideas, we dont want to alter the bottom end at all, but there seems to be no way of softening the top end without the bottom. ANY IDEAS? lowering compression, reed valve, carburation is good, base gasket/head spacer, different electrics. I'm stuck. please help....... no i'm not switching camps just helping a friend. Quote Link to comment Share on other sites More sharing options...
ridgrunr Posted February 5, 2004 Report Share Posted February 5, 2004 Might try retarding the timing. Used to do it all the time on the Fantics, andwe do that on a lot of the GAS GAS TXT's to help them get smoother more tractable power. Not sure how that works on a Pro as I've never dealt with one yet. But retarding the timing works great to mellow out the power throughout the power band, and costs nothing to do. Might also put a slow throttle tube on it. The white ones are fast, and the black ones are slow. They help make the throttle no so explosive. Both are cheap to do. Quote Link to comment Share on other sites More sharing options...
copemech Posted February 6, 2004 Report Share Posted February 6, 2004 I was told by the US importer that the ignition timing was software adjustable for varying conditions and that there were about four standard timing curves and a custom template. Not sure exactly how it all works but you probably need the software and a laptop. Quote Link to comment Share on other sites More sharing options...
jtt Posted February 6, 2004 Report Share Posted February 6, 2004 The '04s apparently have the programmable ignition, but haven't seen one up close to confirm this (it was also reported on earlier models, but never actually appeared). There is some room to slot the pickup mount holes, but not alot. Some retard does help though. Lowering compression usually is most noticable at the bottom and may make it seem worse. I've not played with different reeds, but they can change power characteristics to some degree. You say the jetting is good, but perhaps try fattening up the main. This will often take the "snap" out of the top without effecting much below 1/3 throttle. Other than that, custom porting or lots of clutch control are the last options that I can think of Quote Link to comment Share on other sites More sharing options...
jrsunt Posted February 6, 2004 Author Report Share Posted February 6, 2004 retarding the ignition will alter the power throughout the rev range. will have to look into the programmable ignition, need to speak with someone at the factory i guess. Tryin a larger main jet may be a benefit. will give it a try. Cheer all. Quote Link to comment Share on other sites More sharing options...
shootis Posted February 6, 2004 Report Share Posted February 6, 2004 Hi, In talking to several people they have great luck in mellowing out the Pro's by simply removing the flywheel key and reinstalling the flywheel without the key. When putting the flywheel on the shaft you turn the flywheel counter clockwise one half of the thickness of the key. The key is there mostly for alignment as the shaft uses a Morse taper. It's cheap and easy and fully reversible. Hope this helps Quote Link to comment Share on other sites More sharing options...
toofasttim Posted February 6, 2004 Report Share Posted February 6, 2004 In talking to several people they have great luck in mellowing out the Pro's by simply removing the flywheel key and reinstalling the flywheel without the key. When putting the flywheel on the shaft you turn the flywheel counter clockwise one half of the thickness of the key. 'kin hell, that's a bit drastic isn't it? Why not just retard the timing? Quote Link to comment Share on other sites More sharing options...
jrsunt Posted February 6, 2004 Author Report Share Posted February 6, 2004 THE STATOR PLATE ON THE PRO IS FIXED AND CAN'T BE ADVANCED OR RETARDED. Quote Link to comment Share on other sites More sharing options...
jtt Posted February 6, 2004 Report Share Posted February 6, 2004 THE STATOR PLATE ON THE PRO IS FIXED AND CAN'T BE ADVANCED OR RETARDED. ..at least not without some grinding/filing Many years ago you used to be able to get "offset" keys for just the purpose Shootis is referring to. Suppose you could file one, if you really were concerned about it. Quote Link to comment Share on other sites More sharing options...
t-shock 250 Posted February 6, 2004 Report Share Posted February 6, 2004 Did you not notice this when you had a test ride of the bike before purchasing? What is the difference in power delivery between the Raga rep and a normal 280 pro? Quote Link to comment Share on other sites More sharing options...
jrsunt Posted February 6, 2004 Author Report Share Posted February 6, 2004 if you read the origional post, you'll find it's not my bike, just helping a friend. Quote Link to comment Share on other sites More sharing options...
toofasttim Posted February 6, 2004 Report Share Posted February 6, 2004 THE STATOR PLATE ON THE PRO IS FIXED AND CAN'T BE ADVANCED OR RETARDED. 'mm there goes the pro in my opinion, unless the ignition is programmable. If anybody finds out how to adjust it let us know. BTW don't shout. How was I to know the stator plate is fixed? Quote Link to comment Share on other sites More sharing options...
t-shock 250 Posted February 6, 2004 Report Share Posted February 6, 2004 Oh yeah, sorry didn't see that bit! Quote Link to comment Share on other sites More sharing options...
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