Here is the tuning portion of my build thread. Build thread is here...
http://www.mopedarmy.com/forums/read.php?7,3945059,3945619
Followed the new kit break in wiki. I probably had a few more idle on stand break in steps than what the wiki stated. But I had an oil leak... Which I found to be where the clutch cable goes into the case, fixed with just a drop of loctite. And I had a throttle cable that was too tight and thought I had an air leak because it idled so fast. That's all fixed and it idles with the air screw 1.5 turns out and the idle screw set just so the wheel starts to spin on the stand.
The VM20 ships new with a 22.5 idle and a 180 main. It ran ok through all of break in but wasnt very crisp.
I now have a 20 idle and 160 main. I'm using a VDO 40mph speedometer for any references to speed. When takeoff from a stand still, the bike takes off ok but at 10mph, it clears it throat. At first I thought it shifted into 2nd and thought wth? But then it actually shifts at ~28mph and pulls nicely to top out as 44mph indicated.
I think the hiccup at 10mph is the transition from the idle jet to the main. I think the main is too big and it hesitates at low speed. I don't think it's a lean bog because it pulls. Ice to top speed.... Any suggestions on going up or down with the main? 44mph is great but boy I'd like to crack 50mph which I've read is quite possible with this setup.
http://www.mopedarmy.com/forums/read.php?7,3945059,3945619
Followed the new kit break in wiki. I probably had a few more idle on stand break in steps than what the wiki stated. But I had an oil leak... Which I found to be where the clutch cable goes into the case, fixed with just a drop of loctite. And I had a throttle cable that was too tight and thought I had an air leak because it idled so fast. That's all fixed and it idles with the air screw 1.5 turns out and the idle screw set just so the wheel starts to spin on the stand.
The VM20 ships new with a 22.5 idle and a 180 main. It ran ok through all of break in but wasnt very crisp.
I now have a 20 idle and 160 main. I'm using a VDO 40mph speedometer for any references to speed. When takeoff from a stand still, the bike takes off ok but at 10mph, it clears it throat. At first I thought it shifted into 2nd and thought wth? But then it actually shifts at ~28mph and pulls nicely to top out as 44mph indicated.
I think the hiccup at 10mph is the transition from the idle jet to the main. I think the main is too big and it hesitates at low speed. I don't think it's a lean bog because it pulls. Ice to top speed.... Any suggestions on going up or down with the main? 44mph is great but boy I'd like to crack 50mph which I've read is quite possible with this setup.