Hello.
I would consider getting either a 4-stroke or a morini for my next engine.
How is the power and acceleration of a morini? Is any pedaling required? I'm talking about an S6S, or even that 11hp water cooled one.
Can expansion chambers and shift kits be reused?
What mounting hardware do I need to convert from a standard skyhawk?
The Morini is way more powerful than any "HT" motor, with the proper drive train peddling would be optional, the problem is the S6-S and its water cooled brother "get on the pipe" to far up in the rev band, remember these are RACE motors.
The clutches are finicky, meaning they need to be adjusted properly to engage in the lower part of the rev band, then you have the problem of to much power for the bicycle drive train.
You would have to build a stronger custom jack shaft kit with stronger 415 chain and sprockets, the bicycle drive system wont take 11hp, I've tried it, I got to to work but it cost way to much, I had to build/rebuild and or modifie every part of the drive train.
At the moment, my everyday ride is a modified GT5R 66cc HT motor/shift kit/centerfugal clutch/SPB exp. pipe/ 9 speed.
It wasn't easy to get the chain lines right but shes got great range and theres more gear ratios to play with, shes got a gear for any riding situation, from plunking over rocky trails and city pot holes and curbs to flat out top speed night running.
You have to watch your power delivery, you cant just whack the throttle open, you have to be in 2nd or 3rd gear,ease the power on, and peddle for maximum acceleration efficiency, once shes over 15-20 mph you can hammer it.
I had a Morini S6-t 5hp motor bolted up to a SPB shift kit with custom made mounts, it worked, but parts broke and it took to long to and cost to much fabricate the mounts and up grade the bicycles drive train.
I've stopped building the high powered jobs (Morinis, big 2 or 4 stroke singles) with shift kits, in this case? simple is better.
Its better to just use the left side sprocket with a high powered engine, and Just leave the bicycles stock drive train intact. If you need it at all, as on a race or show bike.
On a bike that's going to be used on the street for commuting or just riding, you still need the stock drive train to "limp home" just in case she gives you trouble.
On my HT/shift kit bikes, I use a master link on the left side motor/jack shaft sprocket chain just so I can remove the chain quickly, so I don't have to spin the clutch as well as the jack shaft as I peddle, even with the clutch in its still spinning and that costs alot of peddle drag.
No one wants to have to push it home 5 miles.
(been there, done that, no thank you)
Just my 2 cents worth.
FR
BBB