what belt & rollers for better performance on the 'top e
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- kmrcstintn
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what belt & rollers for better performance on the 'top e
I want to gain some 'top end' performance on my Buddy 125 while keeping the warranty in effect and was told to change the belt & rollers to do this, ssooo...
what belt and rollers would give me better top end?
what belt and rollers would give me better top end?
- spr0k3t
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Rollers really can't change your top end... but they can help with the tuning. A bad tune will limit the top end sacraficing top end for acceleration or vice verse. The belt will not do anything for you either unless you go with an off sized belt. Trying to get more top end out of the belt could get costly. The best way to get more speed is always in the engine. Fine tuning the clutcth, belt, weights etc may only yeild at best an extra 1mph due to a better tuning for your riding style and personal weight.
- agrogod
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Re: what belt & rollers for better performance on the 't
If your only looking for a few miles (1mph - possibly 5mph) a heavier weight can give you this but not to heavy. You need to find out what your stock weight is and start out with maybe a half gram heavier. If this gives you that ever so small increase then your good, if not then continue up until you get what your looking for, or you get a performance hit (excessive loss of power/acceleration), then drop down to the last good weight.kmrcstintn wrote:I want to gain some 'top end' performance on my Buddy 125 while keeping the warranty in effect and was told to change the belt & rollers to do this, ssooo...
what belt and rollers would give me better top end?
A roller tuning kit is good for this type of approach. When you find your "sweet spot" you can stick with rollers or switch over to slider weights of the weight you need.
Just keep in mind that going up in weight will give you an acceleration hit, so you must decide if it is going to be acceleration or speed.
As for the belt, it is true that while it won't really give any speed increase, its more of a personal choice. Standard vs. Kevlar.
"When your mouth is yapping your arms stop flapping, get to work" - a quote from my father R.I.P..
always start with the simple, it may end up costing you little to nothing
always start with the simple, it may end up costing you little to nothing
- Skootz Kabootz
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A belt won't make any difference at all to the speed of your scooter, unless of course it is loose or it breaks...
... On kevlar vs non-kevlar, I have heard of kevlar belts doing damage when they break as they tend to shatter into pieces which can cause problems. Non-kevlar belts generally just break. Some people like kevlar, some don't. IMO the stock Buddy engine does not create anywhere near enough torque where kevlar's strength would come into play and be of benefit.
As for rollers/sliders, they will not increase your scooters top end speed. Top end speed, as far as the transmission is concerned, is a product of the gear ratio created by the position of the belt on both the driving and driven pullies. Once the belt is all the way to the outside of the driving pulley (the variator) and the inside of the driven pulley, there is no more speed to be gained via the transmission. This is what ideally you want to achieve.

All that said, if at high speed your belt is not getting all the way to the outside of the variator then yes, a little more roller/slider weight (.5g or maybe 1g above stock) could help get the belt all the way to the outermost edge of the driving pulley (thus increasing the gear ratio and top end). But adding that extra roller/slider weight will cost you in off the line performance.
A simple performance test you can do is to take a magic marker and draw a line from the inside edge to the outside edge of your variator then go for a ride at WOT. If your belt has full travel and is getting all the way to the outer edge of the variator, all the marker will be worn away by the belt. If not, the remaining marker will show you where the belt is stopping.

As for rollers/sliders, they will not increase your scooters top end speed. Top end speed, as far as the transmission is concerned, is a product of the gear ratio created by the position of the belt on both the driving and driven pullies. Once the belt is all the way to the outside of the driving pulley (the variator) and the inside of the driven pulley, there is no more speed to be gained via the transmission. This is what ideally you want to achieve.

All that said, if at high speed your belt is not getting all the way to the outside of the variator then yes, a little more roller/slider weight (.5g or maybe 1g above stock) could help get the belt all the way to the outermost edge of the driving pulley (thus increasing the gear ratio and top end). But adding that extra roller/slider weight will cost you in off the line performance.
A simple performance test you can do is to take a magic marker and draw a line from the inside edge to the outside edge of your variator then go for a ride at WOT. If your belt has full travel and is getting all the way to the outer edge of the variator, all the marker will be worn away by the belt. If not, the remaining marker will show you where the belt is stopping.
- k1dude
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If you want a higher top end, you need heavier sliders, not lighter. Your 11g sliders are lighter than stock - which will provide you with better acceleration, but will hurt your top end.lovemysan wrote:The stock rollers limit my top speed at 250 lbs. My current setup is 11 gr sliders , 161 kit, prima pipe. No change in top speed.
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This is not always true. My actual gps top speed is 49 mph. Heavier weights did not improve top end for me. I'm 6' and 250lbs. If I was smaller I think heavier weights would helpk1dude wrote:If you want a higher top end, you need heavie sliders, not lighter. Your 11g sliders are lighter than stock - which will provide you with better acceleration, but will hurt your top end.lovemysan wrote:The stock rollers limit my top speed at 250 lbs. My current setup is 11 gr sliders , 161 kit, prima pipe. No change in top speed.
- k1dude
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Hmm. I see what you're saying. You weigh enough to where the engine is too loaded to achieve higher RPM's, which in turn doesn't allow heavier sliders to radiate all the way outward. At least I think that's correct theoretically.lovemysan wrote:This is not always true. My actual gps top speed is 49 mph. Heavier weights did not improve top end for me. I'm 6' and 250lbs. If I was smaller I think heavier weights would helpk1dude wrote:If you want a higher top end, you need heavie sliders, not lighter. Your 11g sliders are lighter than stock - which will provide you with better acceleration, but will hurt your top end.lovemysan wrote:The stock rollers limit my top speed at 250 lbs. My current setup is 11 gr sliders , 161 kit, prima pipe. No change in top speed.
- JettaKnight
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