Variator rollers & contra Spring

Harddog96

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So I’m currently in the process of tuning my moped I’ve got it all broken after my engine rebuild and what not but I don’t know much about any mechanical stuff so I’ve had to YouTube and look at forms. Anyways.
Can anyone tell me I have 5 to 6 g rollers and 6 to 7 g rollers I also have a contra Spring that is 42kg and one that is 45kg. Right now I’m running the lightest of them. What would be for the best performance?
 

Cannonball3

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Depends on what you want. I ran a big bore Gy6 Rukus clone. It had the torque to pull down low so I tuned the variator with heavy weights, and a lighter spring. Was immediate of the line and up ratioed quickly. I imagine you may want the other direction with lighter weights being a 2stroke. You need to figure when your engine bands and set the weights around that engagement for quickest response for max acceleration. Set below it lags, above take more revs and may miss the engines power range Initially. Its all experimentation. I think as I remember I mixed rollers heavy and light to get the fastest low end. The light rollers kept the balance. By the time it was all over I had tons of all size rollers, springs, longer belts, larger sheaves, and up ratio gear sets. Was a lot of fun to experiment with.
 

Harddog96

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How would I figure out the engine band. I got the stage six street race in exhaust it says that it’s better for high RPMs. I also have a tachometer on there.
 

Cannonball3

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Ride it and note when the engine begins to come alive and at what rpm. If say 5k for example ,then for max take off the weights should allow the engine to rev to that speed pretty immediately. That allows the power to be developed quickly to begin take off and up ratioing. You may not want it that way. For more sedate riding heavier weights allow earlier engagement and a slower climb to speed. On my 212 golf cart it engaged at 2200. The engine was reving a good bit before pull away. I did just the oppsite and lowered the engagement to1800. Its a much nicer to use with a quicker/earlier pull away, Its not as quick on acceleration but more pleasant to use for a slow speed vehicle. You have to determine what you want.
 

DieselTech

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Also like I mentioned in your other thread, if your a big dude you need heavier roller weights, if your a little dude you are going to want lighter roller weights. You also can shim your drive face in or out also to help tune for your desired rpm range.
 

Harddog96

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OK and I said just putting the little shims in between the variator in that long tube that the bell sits on? And I’m small 135-140 lbs only 5’8”
 

DieselTech

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OK and I said just putting the little shims in between the variator in that long tube that the bell sits on? And I’m small 135-140 lbs only 5’8”
I'm a 150lbs & I was recommended by scooterswapshop to run 3.5-4.5gram rollers for my particular driving habits. I'm running 5gram rollers with 3 .010" shim between my drive face. I only used the shims to put the belt down lower on the drive pulley to increase my take off. I'm running the yellow contra spring till I get big bore kit installed. You can stagger your roller weights also if need be to achieve your particular driving habits.
 

Harddog96

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OK say I was curious if you could interchange like a 5,6 with a 6,7. But I already have a 70cc motor that I put into it I just did the whole engine swap here recently I have a whole Nother post on this form about it but I’m just learning as a go. So far so good though I’ve got it to go 52 mph. my exhaust says I need 10,000 RPMs, the motor also says it’s best at 10,000 RPMs that’s just what I’m trying to achieve I can only hit 9850 is my max. I was going to buy those shims off of SSS, but haven’t yet I might get on that.
 

DieselTech

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OK say I was curious if you could interchange like a 5,6 with a 6,7. But I already have a 70cc motor that I put into it I just did the whole engine swap here recently I have a whole Nother post on this form about it but I’m just learning as a go. So far so good though I’ve got it to go 52 mph. my exhaust says I need 10,000 RPMs, the motor also says it’s best at 10,000 RPMs that’s just what I’m trying to achieve I can only hit 9850 is my max. I was going to buy those shims off of SSS, but haven’t yet I might get on that.
Depending where you want your powerband & say shift point, if you got a real stiff contra spring, you might want to go to the next lighter spring. What you might want to try is put 8,9,,10 gram rollers in & see if your max rpm increases or decreases. If it decreases significantly, you know then you need to go lighter on your rollers. Also the shims on the drive pulley/face will reduce your top speed, but you will gain take off torque.
 

Harddog96

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Said I did have the latest one in there but I was only getting like 7000 RPMs and when I swap that out and tightened the actual clutch springs and put stiffer ones in it almost hit 10 so I’m wondering if the variators the problem. Maybe I should go to the heaviest variator rollers and go back to lighter stuff in the clutch both contra spring and clutch springs
 
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