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Post by stepthrutuner on Apr 4, 2013 21:27:49 GMT -5
I suggest going back to the stock contra and experiment with bushing it up with the ball bearing aftermarket rest and/or the Malossi plastic rest or some other measure to get extra counter force back there in varying degrees. You might have to try six or more different combinations of roller weights/contra spring spring pressures till you like the effect. As others said, the straight (non-curved) aftermarket slotted torque drivers may help you as well to maintain a constant acceleration with constant rpm till the pulleys max out. A carb needle with more taper (and perhaps a bit shorter) could help with soft seizes. It's pretty hard to get carb fueling absolutely perfect once you start messing with a bigger carb or different pipe or tranny mods. You just have to get it right for MOST of your riding style and situations. There IS a reason they call it scooter-tuning and it is not cut-and-dry but rather trial-and-error mostly and it IS time-consuming.
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Post by aznatama on Apr 4, 2013 23:11:17 GMT -5
I'm using 5g rollers w/ 1500 contra right now. 4.75 seemed to be perfect, but now with heavier weights, I seem to take off like a rocket, then it shifts and it drops the RPMs for 1/2.
Also, after adding a bit of oil to the tank, I seem to be running noticeably lean at WOT, sounds like the engine is losing power. It's at about 50:1 now, I'll fill up tomorrow to dilute it to a little over 100:1 depending on how much I fill up.
Perhaps my soft seizes were from lack of oil... no idea really. But this variator tuning is a pain too. Thought I had it set, now with a .25g shift in roller weight, I have this comppletely unacceptable issue. FML It didn't act like this last time I had 5g weight in, the "surge" was MUCH less dramatic.
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Post by ryan on Apr 4, 2013 23:48:38 GMT -5
so drain your oil somehow un plug your oil line to carb and then plug the inlet on carb for injection..fill up and add 3.5-4 ounces of oil to tank and shake your tank around till mixed..if its not loosing speed and not getting hot etc also doesnt have bad symptoms then you know your pump is either not putting enough out or it is not working
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Post by usmcdoc on Apr 5, 2013 7:34:59 GMT -5
so drain your oil somehow un plug your oil line to carb and then plug the inlet on carb for injection..fill up and add 3.5-4 ounces of oil to tank and shake your tank around till mixed..if its not loosing speed and not getting hot etc also doesnt have bad symptoms then you know your pump is either not putting enough out or it is not working As ryan said.....your oil pump may be bad. Mine has never worked even since new...I soft seized MANY times and ruined 2 top ends. Finally added 32:1 gas/oil to the tank...ran it at wot on the stand....pullled oil line from carb and after about one minute..only ONE drop of oil came out. Bled the pump...tried it again...same thing. So now I premix until I talk ryan into putting a new pump in for me.(I am an excellent scooter Mech...but I have poor vision even with glasses..can't see up close) Any 50:1 is pretty lean...100:1 is outta the question even though some synthetic oil companies guarantee their oil is designed to handle 100:1. I tried it once on my RM250...seized tight within 100 yards and ate a new $200 cylinder and $130 Wiseco piston. Call them and try to get them to honor the guarantee...they won't. You have to send them the parts at your cost and they tell you the fuel main jet was too lean. I don't recommend 50:1 either...I had probs with that..several mini soft seizes. At 32:1 it is right on! Not even a hint of soft seize. With the BBK...1.5k springs....87.5 jet..needle raised one notch... Take off is right now! 0-30 in about 50 feet...then 30-50 to 55 another 200 feet or so. ryan has ridden my lil green rocket..he will tell ya. Of course nothing close to his maxed out build..I doubt anything can touch that thing...holy smokes. Bottom line...very oil pump output..also many do not know that your oil pump is adjustable. When I sold scoots..the first thing I did on the 2T ones was adjust the pump. It has two marks that you line up...and from the factory nearly EVERYONE of them came set 5mm behind the alignment marks..making them not lean at idle....it made them put out absolutely no oil..so long idles caused premature wear and at 1/2 throttle they were only getting the amount of oil they need at idle...which made them very oil lean at WOT. Here is a link to some very important info I posted...Brent added to it some direct info from the engine manufacturer that probably less than 1 in 10 folks know about. Please read ---> 49ccscoot.proboards.com/thread/3151/avoiding-soft-seize-pump-adjustment
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Post by aznatama on Apr 5, 2013 11:52:45 GMT -5
I've read that, and like my other post on the soft seize issue, I have my oil pump maxed out. It's a mikuni pump, and appears to be working. however, I'll pull the line and check it.
It's really a pain to premix, which is why I wanted to keep the auto-lube. Hope this is not an autolube issue. I have nowhere to drain the oil except back into my oil bottle, and then i'll have to re-use the oil. I think it will get contaminated this way, so I don't want to risk it. If the autolube is working, then I think 100:1 in the tank should be fine for that extra little bit of oil.
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Post by usmcdoc on Apr 5, 2013 12:49:48 GMT -5
I've read that, and like my other post on the soft seize issue, I have my oil pump maxed out. It's a mikuni pump, and appears to be working. however, I'll pull the line and check it. It's really a pain to premix, which is why I wanted to keep the auto-lube. Hope this is not an autolube issue. I have nowhere to drain the oil except back into my oil bottle, and then i'll have to re-use the oil. I think it will get contaminated this way, so I don't want to risk it. If the autolube is working, then I think 100:1 in the tank should be fine for that extra little bit of oil. Well I am possibly barking up the wrong tree then...2 things I have yet to see fail in my 41 years of riding....1. Boyesson Reeds..2. Mikuni oil pumps... I know what ya mean about premixing....a pain. Went to visit my mother...was down to 1/4 tank of gas and needed more to get home...so I had to buy oil and guess at the gas station...it was like "Ok says 1/4 tank..but these gauges are not always right...looks like more than 1/4 tank..hmm 32:1 I add 4 oz to one gallon...so I would need 3oz instead?.." So I added 3 oz and tank was fuller than gauge said when I filled it.. so oil mix was rich..probably 20:1 or more. All I know is on the way home it smoked like crazy...had it been summer I could have killed every Mosquito along that 27 mile ride..
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Post by aeroxbud on Apr 7, 2013 17:23:54 GMT -5
When i used to premix on the RD i used to go by how much petrol i had put in the tank on the pump readout. Just have to put in 2,3,4 ltr ect. Then you know how much oil to mix. Used to get some funny looks paying for gas though, was always weird amounts like £5.38 lol
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