Post by thecableguy on May 25, 2010 13:14:32 GMT -5
Ok, so I see a lot of posts on here from new 50cc owners looking to go faster or having problems with hills etc. I figured I'd share my experience with getting my Roketa up to speed.
I haven't put a BBK on it yet and I may not with the performance I'm getting now.
When I bought it, it took forever to get to 25 and needed a hill or a tailwind to get to 30. RPM wouldn't get past 5500. After driving it around town a bit I realized I needed better acceleration off the line and a bit more top speed to keep up with traffic. Not too many hills here in town but there is a couple of viaducts (bridge over RR tracks) with steep approaches. Going up the 21st St. viaduct slowed me to 15.
The first thing I did was replace the sparkplug with an NGK Iridium during my PDI. I removed the inner tube in the stock airbox to open the flow up a bit. I noticed I was running quite lean so I also swapped out the main jet (I think an 85 is in there now). I also adjusted the tire pressure.
This helped a bit but I still couldn't get the RPMs up into the powerband. New rollers did that. The stock rollers were either 7.5 or 8g and were WAY too heavy for me (I'm 215#). I tried 5.5 and then 5g and found the 5g to work the best. I found now the engine would rev to 7500 and I was faster than most of the cars off the line. Top speed had increased to around 35 as the engine was now operating closer to the powerband. I also installed a Gates Powerlink belt. That didn't seem to affect the speed, but it helped my peace of mind that the belt wasn't going to shred in the first 500 miles...
I picked up a set of 5g knockoff sliders from Scrappy. These seemed to help a bit as the engine would rev a bit higher and stay there better on hills. Climbing the viaduct was up to 25. I also put in one of the orange "race" CDIs from Scrappy. This didn't seem to change the performance, but the starting (particularly warm starting) and idling was improved.
I then bought an NCY variator from Enviro and put the sliders in it. That made a big difference too. Same acceleration off the line but higher RPM peak (around 8300) and higher top speed, 40MPH on flat ground no wind, GPS verified. I can also maintain 35 up the viaduct now and over 40 downhill or with a tailwind.
Still using the stock exhaust, airbox and carb. Now I realize that a bunch of folks around here claim 50 for their heavily-modded 72cc or larger scoot. I figure 40 out of a stocker is pretty good.
So to review,
Complete PDI including valve adjust
Replace sparkplug
Remove restrictor in airbox
Re-jet
Check tire pressure
Lighter rollers/sliders
CDI
NCY variator
Everything else is stock.
Total $ invested, around $65. A few hours spent pleasantly tinkering in the garage...
Jim
I haven't put a BBK on it yet and I may not with the performance I'm getting now.
When I bought it, it took forever to get to 25 and needed a hill or a tailwind to get to 30. RPM wouldn't get past 5500. After driving it around town a bit I realized I needed better acceleration off the line and a bit more top speed to keep up with traffic. Not too many hills here in town but there is a couple of viaducts (bridge over RR tracks) with steep approaches. Going up the 21st St. viaduct slowed me to 15.
The first thing I did was replace the sparkplug with an NGK Iridium during my PDI. I removed the inner tube in the stock airbox to open the flow up a bit. I noticed I was running quite lean so I also swapped out the main jet (I think an 85 is in there now). I also adjusted the tire pressure.
This helped a bit but I still couldn't get the RPMs up into the powerband. New rollers did that. The stock rollers were either 7.5 or 8g and were WAY too heavy for me (I'm 215#). I tried 5.5 and then 5g and found the 5g to work the best. I found now the engine would rev to 7500 and I was faster than most of the cars off the line. Top speed had increased to around 35 as the engine was now operating closer to the powerband. I also installed a Gates Powerlink belt. That didn't seem to affect the speed, but it helped my peace of mind that the belt wasn't going to shred in the first 500 miles...
I picked up a set of 5g knockoff sliders from Scrappy. These seemed to help a bit as the engine would rev a bit higher and stay there better on hills. Climbing the viaduct was up to 25. I also put in one of the orange "race" CDIs from Scrappy. This didn't seem to change the performance, but the starting (particularly warm starting) and idling was improved.
I then bought an NCY variator from Enviro and put the sliders in it. That made a big difference too. Same acceleration off the line but higher RPM peak (around 8300) and higher top speed, 40MPH on flat ground no wind, GPS verified. I can also maintain 35 up the viaduct now and over 40 downhill or with a tailwind.
Still using the stock exhaust, airbox and carb. Now I realize that a bunch of folks around here claim 50 for their heavily-modded 72cc or larger scoot. I figure 40 out of a stocker is pretty good.
So to review,
Complete PDI including valve adjust
Replace sparkplug
Remove restrictor in airbox
Re-jet
Check tire pressure
Lighter rollers/sliders
CDI
NCY variator
Everything else is stock.
Total $ invested, around $65. A few hours spent pleasantly tinkering in the garage...
Jim