rubberneck Posted October 3, 2009 Report Share Posted October 3, 2009 Ok, i am hoping that some of you guys have spent some time playing with a dyna fs ignition. I made the cardinal mistake of changing 2 things at once, and now im not sure where to start. Background: I have a hot dune ported motor by HJR, that initially had T5s on it when i got the bike. (HQ give away bike) I am turning the HQ bike into a drag bike and istalling my cub, so i put that motor in my duner. Now when the motor came from kevin, the timing was set at +6. So when i put the motor in my other bike i put the plate to +2 and set the dyna on curve #3. Now the motor feels like it is laying over on the top. It just kind of stops pulling. The problem is i also switched from the T5s to shearers. Ive tried going up and down 2 jet sizes on the mains, but it doesnt seem to fix the issue. So im not sure if the issue is in the ignition, or what. I would assume the shearers would help on top, and Kevin told me the motor was originally ported for shearers anyway. I guess what my question is have any of you guys had problems with the dynas not acting right? I am wondering if the motor just needs more advance at the higher rpm, but that would seem backwards. I am going to try switching the plate back to +6 and plugging my OEM CDI in today. If it still isnt acting right ill stab the t5s back on and see if it is back to normal. Again that just doesnt seem correct. If anything i would have expected the bottom to fall off and top to pick up with the shearers. It does take a little longer to come into the power, but not too bad, and then it pulls hard, but the last bit where it lays over has me stumped. This is where the shearers should shine. just figured i would throw it out there and see what information I could dig up on the dynas. I dont really see much discussion on here about them, so my guess is they must not give people trouble or you would hear about it. Quote Link to comment Share on other sites More sharing options...
Snopczynski Posted October 3, 2009 Report Share Posted October 3, 2009 Well I think I would try curve 1,2, or 4 and see if the pull gets better. Curve 3 is kind of a low-mid curve. With the higher revving pipes your gonna want less advance on the top than what you were previously running, because it will be achieving more rpm. Curve 4 is the stock curve in the dyna, so using that with +2 on the plate will be 4 degrees less advance than what you were using with the stock cdi and +6 on the plate. Curve 1 and 2 have some high initial advance at lower rpm, then back off a bit sooner than curve 3 through the midrange and top end. Quote Link to comment Share on other sites More sharing options...
coronakidd Posted October 3, 2009 Report Share Posted October 3, 2009 I have had a custom programed dyna drop the program and run like crap had it reprogramed and it works fine i also had a stock dyna never had any problems put plate on 0 setting my switch is marked stock curve,curve 1(+4),curve 2 (+7),curve 3 (nitrous)that is what i was told set mine at 4 on rider,got my drag bike set on 8 and took the custom programed dyna and sold it and run stock box Quote Link to comment Share on other sites More sharing options...
rubberneck Posted October 4, 2009 Author Report Share Posted October 4, 2009 Well I think I would try curve 1,2, or 4 and see if the pull gets better. Curve 3 is kind of a low-mid curve. With the higher revving pipes your gonna want less advance on the top than what you were previously running, because it will be achieving more rpm. Curve 4 is the stock curve in the dyna, so using that with +2 on the plate will be 4 degrees less advance than what you were using with the stock cdi and +6 on the plate. Curve 1 and 2 have some high initial advance at lower rpm, then back off a bit sooner than curve 3 through the midrange and top end. Snop, if I am correct all the curves end up back down at the same point in the upper rpms correct. I dont have the paperwork in front of me right now, but it seems that was what i remember. It is just differences in how long they maintain the initial advance right? I think the thing that baffled me was that using curve 1 2 or 3 and the plate at +2 i should have less advance in the higher rpms than i did with the stock curve and +6 right. I figured this would do nothing but help on top with the shearers and the extra rpm. I figured the # 3 curve would help keep some of the mid that i would lose with the shearers. Anyway, i played with it a lot today, and i think i have it running pretty strong. Part of the problem honestly i think is me. The last time i rode this particular bike it had my 421 cub in it, and that thing just never ran out of steam. I think it is just different caracteristics of the motors. This motor has better mid range and less on top where as the damn cub just never stops. Looking forward to getting it in the sand next week, i think this will be a better dune motor than the cub. thanks for the info. Quote Link to comment Share on other sites More sharing options...
Snopczynski Posted October 4, 2009 Report Share Posted October 4, 2009 Curve 1,2, and 3 end at 4 degrees of advance above stock. So +2 on the plate puts you at +6 overall with those 3 curves, but midrange advance will be alot more aggresive with curve 3. Curve 4 is the stock curve. Most of the mid-top ignitions I program for guys are based off curve 1 or 2 with varying advance on the bottom, and retard on the top. Quote Link to comment Share on other sites More sharing options...
rubberneck Posted October 4, 2009 Author Report Share Posted October 4, 2009 Curve 1,2, and 3 end at 4 degrees of advance above stock. So +2 on the plate puts you at +6 overall with those 3 curves, but midrange advance will be alot more aggresive with curve 3. Curve 4 is the stock curve. Most of the mid-top ignitions I program for guys are based off curve 1 or 2 with varying advance on the bottom, and retard on the top. Awesome thanks snop. I am going to have to tinker more. Sounds like i may be doing a custom program. Ill see how i like the motor in the sand next week. Do some fine tuning Quote Link to comment Share on other sites More sharing options...
RadarRacing Posted October 11, 2009 Report Share Posted October 11, 2009 just a thought but shearers stuff the cylinders a lot more than T5's and sometimes need about 2 jet sizes less up top than the t5s. The T5s are easier to jet and run well IMO cuz even off 3 jet sizes they run well. If you are rich much on the shearers they will either be a dog off the line or kinda not rev out up top. When right they fly. Quote Link to comment Share on other sites More sharing options...
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