moby still won't hit top speed

Finally thought I had everything worked out to get my stock-ish 50v hitting the 30mph the headbadge says it's supposed to. Running a 14.12 SHA with a 54 jet, plug chops look good. After downjetting from the 57 that came with the carb, the bike picked up a couple mph, topping out around 26mph or so, but I am afraid to downjet any more as the plugs are showing the bike running on the lean side of acceptable. Replaced the blunderbuss with the AV88 cashew replica from '77. No air leaks, good compression. What else could be slowing me down? Starting to get real puzzled as to why it won't hit that 30mph mark...

Re: moby still won't hit top speed

new rings bearings and seals?

chain too tight?

Re: moby still won't hit top speed

All that stuff is original as far as I know. Chain tension looks good. It's got 1500 original miles. Would rings, bearings and seals be something that would need replacing at this point, considering that the bike probably sat for a while before the previous owner (who had it for 10 yrs. and rode it intermittently) started riding it? I'm a little too much of a noob to feel comfortable with pulling apart my engine, so I want to see if there's anything else it could be before getting into that.

Re: moby still won't hit top speed

Timing probably needs to be indexed and set for initiation at 1,5mm BTDC.

http://mabecanemobylette.freeforums.org/ignition-timing-initial-setup-t1036.html

100% stock 30mph with a SHA 14:12 should take a jet around 53ish so if she is very lean then you might have a vacuum leak. Give it a leak down to see if extra air is getting in there, if your SHA is not oringed then you might want to do that http://mabecanemobylette.freeforums.org/dellorto-oring-sealing-t1769.html

Re: moby still won't hit top speed

Also, you might think about servicing your variator and perhaps throwing a new belt on there. It's amazing how much potential is in there.

Re: moby still won't hit top speed

What would servicing the variator involve? I greased it through the grease port recently. I was under the impression that that was the extent of it. Is there more I can do?

Re: moby still won't hit top speed

im highly interested in this part if anyone knows of a var servicing tut that would make me super randy

Re: moby still won't hit top speed

All you need to k now and more about Moby variators http://mabecanemobylette.freeforums.org/variator-and-clutch-f30.html

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